Tw e n t y - F i r s t C e n t u r y B o o k s Minneapolis
This book is dedicated to Frank Winter
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Tw e n t y - F i r s t C e n t u r y B o o k s Minneapolis
This book is dedicated to Frank Winter
Text and illustrations copyright © 2008 by Ron Miller All rights reserved. International copyright secured. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means—electronic, mechanical, photocopying, recording, or otherwise—without the prior written permission of Lerner Publishing Group, Inc., except for the inclusion of brief quotations in an acknowledged review. Twenty-First Century Books A division of Lerner Publishing Group, Inc. 241 First Avenue North Minneapolis, MN 55401 U.S.A. Website address: www.lernerbooks.com
Library of Congress Cataloging-in-Publication Data Miller, Ron, 1947– Space exploration / by Ron Miller. p. cm. — (Space Innovations) Includes bibliographical references and index. ISBN-13: 978–0–8225–7155–1 (lib. bdg. : alk. paper) 1. Astronautics—History—Juvenile literature. 2. Outer space—Exploration— History—Juvenile literature. I. Title. TL793.M5558 2008 629.41—dc22 2007002863 Manufactured in the United States of America 1 2 3 4 5 6 – DP – 13 12 11 10 09 08
The Theorists 16 Chapter 3
The Rocket Riders 28 Chapter 4
First Steps toward the Moon 42 Chapter 5
Apollo to the Moon 54 Chapter 6
Space Stations 70 Chapter 7
The Space Shuttle 86 Chapter 8
The Future 92 Glossary
For Further Information
ver since human beings looked up at the night sky and realized
that some of those twinkling lights were in fact other worlds, they have wanted to travel into space and explore for themselves. Once humans devised ways to leave Earth and explore the universe, most of the exploration was done by robots. These semi-intelligent machines sent back pictures and data from other worlds. This development was exciting, and the data were vital to science, but it was not the same as being there. A satellite in orbit, sending back pictures of Earth below, is not the same as being an astronaut aboard an orbiting space shuttle, camera in hand. Robot explorers are much cheaper than sending humans into space, and nobody’s life is ever at risk. But that’s not always the most valuable way to explore. Humans have always wanted to see things firsthand—to see a strange new landscape with their own eyes, to pick up a rock with their own hands. And human exploration has advantages. The main advantages benefit human intelligence and human curiosity. No machine will ever come to the base of a hill and think, “I wonder what’s on the other side?” This book is about the people and machines that have enabled humans to take those first, tentative steps away from our home world. It is about how humans have been able to see with their own eyes what’s on the other side of that hill on the Moon or on Mars.
Astronaut Ed White of Gemini 4 was the first American to perform a space walk in 1965. Tied to a tether, White floated in space for twenty-two minutes.
Astronautics—the technology of exploring space—is unique among all the sciences because it originated in art and literature. Long before engineers and scientists took the possibility of spaceflight seriously, virtually all of its aspects were explored by artists and writers. And long before the scientists themselves were taken seriously, the arts kept the torch of interest burning. While there had been numerous early fantasies about trips to the Moon, no one really considered the possibility of spaceflight until two important events occurred. First, scientists had to discover that there were places in the universe other than Earth. Second, they had to create technology that made it possible to get there. These two events took place about 250 years apart. Top: In 1638 author Francis Godwin described being carried to the Moon by geese. Middle: In 1657 author Cyrano de Bergerac made fun of Moon travel stories by launching his hero in a rocket. Bottom: In 1865 author Jules Verne shot his astronauts to the Moon from a giant cannon.
7 In 1610 Galileo Galilei (1564–1642) was the first scientist to turn a telescope toward the night sky.
The first event took place in 1610 when the Italian scientist Galileo Galilei turned his telescope toward the sky and discovered that the planets weren’t just a special class of wandering stars. They were real worlds. Venus showed phases just like the Moon, and Mars had dusky markings. Jupiter possessed four tiny moons of its own, like a miniature solar system. At the same time that Galileo and other astronomers were discovering new worlds in our solar system, explorers were finding new worlds on the other side of the Atlantic Ocean. Hundreds of ships and thousands of explorers, colonists, soldiers, and adventurers had made the journey to the rich and fertile lands of the New World discovered on the far side of the Atlantic. Human beings had finally learned that new lands existed here upon Earth, as well as unknown worlds beyond the sky.
Many authors wrote of trips to the Moon in the decades following Galileo’s discovery. In 1622 French author Charles Sorel published a book called Comical History of Francion. He wrote about “great Engins” that might carry people to the Moon. He also wrote that people might get to the Moon by means of “all manner of structures, and ladders.” The scientist Johannes Kepler wrote the novel Somnium in 1634. In this book, the hero is carried to the Moon by demons along a bridge of darkness that occurs during an eclipse of the Moon. Obviously this method of getting to the Moon was highly unscientific. But Kepler’s descriptions of the conditions there were very accurate in the light of what was known about the Moon at that time. For instance, Kepler was aware that most of the journey would have to be made in a vacuum—a space without air or gas. He also said that the surface of
the Moon would be desolate, alternating between extremes of heat and cold. In 1638 Francis Godwin published The Man in the Moone.
In this illustration from the 1683 edition of Bishop Godwin’s fanciful novel The Man in the Moone, its hero is being carried to the Moon by geese that supposedly migrate there.
The discoveries made by astronomers were quickly followed by a wave of space travel stories. Since these new worlds could not be reached in reality, they were explored through fiction. Most of the authors had little or no interest in the realistic depiction of science.
In this book, the hero is carried to the Moon by a flock of geese that regularly migrate between Earth and the Moon. Cyrano de Bergerac made fun of such fanciful voyages in his Comic History (1657). De Bergerac tried to come up with as many utterly ridiculous methods of space travel as he could think of. For example, he had his hero tie bottles of dew to his belt. When the Sun rose, it attracted the dew and carried the hero off into space. (Everyone knew that dew rose from the ground in the mornings.) In another attempt to reach the Moon, de Bergerac’s hero fastened skyrockets—similar to the ones seen in Fourth of July displays—to a large box. De Bergerac became the first author to describe the use of rockets for space travel. Ironically, however, he had only written about rockets because he thought the idea of using them was silly!
This illustration from an early edition of Cyrano de Bergerac’s novel Comic History shows the hero trying to reach the Moon in a vehicle with many rockets attached.
But their books were nevertheless an accurate measure of the everincreasing interest in the possibility of exploring the planets. The second great event—creating the technology—occurred in 1783. Two Frenchmen, brothers Étienne and Joseph Montgolfier,
invented the hot-air balloon. For the first time, human beings were able to ascend above Earth farther than they could jump. This invention launched avalanches of speculative literature about the possibility of traveling beyond Earth and what might be found on the other worlds. Here at last seemed to be an answer to all of those who had been looking at the starry sky with longing. If huThe invention of the hot-air balloon
mans could devise a way of ris-
in 1783 by the Montgolfier brothers
ing a few thousand feet above
showed that humans could rise
the surface of Earth, what was
above Earth by mechanical means.
a mere 250,000 miles (402,335 kilometers) to the Moon?
Science and technology had conquered the sky. It had to be only a matter of time before they conquered space as well. Needless to say, writers quickly abandoned their geese and demons and turned to balloons to carry their heroes to the Moon and all over the solar system. But if science was marching ahead, so were the increasingly knowledgeable readers of these books. A widespread fascination with science occurred at the end of the eighteenth century. Most readers were becoming too knowledgeable about the subject to accept balloons as a realistic method of getting to the Moon. Authors were forced to come up with more realistic, believable methods of space travel.
One of the first to do so was American author George Tucker. The spaceship in his 1827 novel, A Voyage to the Moon, used a mysterious substance that canceled Earth’s gravity. Tucker gave great thought to the actual conditions that might exist beyond Earth’s atmosphere and how his vehicle would have to deal with them. He succeeded in writing the first description of a spaceship that takes into account the actual conditions of outer space. For instance, the spaceship is carefully tested to make sure that it is perfectly airtight. Compressed air for breathing is carried in tanks. The walls are even insulated to protect the astronauts from the cold of space. Tucker was one of Edgar Allan Poe’s instructors at the University of Virginia. His novel may have inspired Poe to write his own Moon travel story: The Unparalleled Adventures of One Hans Pfaall (1835). Although Poe’s character used a balloon for space travel, Poe still paid more careful attention to science than any other author before him. His descriptions of high-altitude flight and of Earth as seen from space could have been written by modern astronauts.
JULES VERNE By the turn of the nineteenth century, the world was undergoing an industrial, technological, and scientific revolution. By the time the Montgolfiers had flown their first balloon, the steam engine had already been invented. Only two years earlier, a new planet, Uranus, had been discovered. In 1783, the same year that the first balloon flew, the steamboat was invented. Soon the first steamship crossed the Atlantic, and the first railways set off. Inventors created the electric storage battery and motor, the telegraph, the camera, and the revolver. People living in the nineteenth century had good reason to think that science could do anything.
Scientists and engineers seemed capable of understanding and overcoming any obstacle. Surely, if humans were going to leave Earth and travel to other planets, science and technology would provide the means. By the mid-1800s, generals, admirals, and explorers had been replaced by a new hero: the engineer. Still, no one seriously considered the technological Jules Verne was one of the most
problems until 1865. That
popular authors in the world during
year French author Jules
the nineteenth century. When he
Verne wrote his classic novel
wrote a scientifically accurate book about a trip to the Moon, many
From the Earth to the Moon.
people believed that it could actually
Before then, all space travel
stories had been fantasies. In the story, a group of
arms manufacturers find themselves with nothing to do after the close of the U.S. Civil War (1861–1865). As an outlet for their energies and creative genius, they propose building an enormous cannon. It would be a well 900 feet (274 meters) deep with 400,000 pounds (181,436 kilograms) of explosives at the bottom. They plan to use it to launch a projectile to the Moon. The characters eventually realize that launching a projectile carrying passengers would be much more interesting than launching an unmanned projectile. In reality, this would never really work.
The shock of going from a standing start to 7 miles (11 km) a second in 900 feet (274 m) would have been instantly fatal to the heroes. But Verne realized this and filled his book with so much science, math, and engineering that his nineteenth-century readers accepted his story without question. In fact, when the novel was first published in France, people wrote to Verne volunteering to be passengers in the projectile! With the publication of Verne’s novel, the possibility of space travel was for the first time put on a firm mathematical and technological basis. Verne’s method of sending his astronauts into space wouldn’t work in reality. But what was important was he suggested a method that employed nothing but known materials and contemporary technologies. His astronauts didn’t need to rely upon hot-air balloons or antigravity metals. He demonstrated to his readers one extremely important fact: the conquest of space was a matter of applied mathematics and engineering.
Realizing that his readers would not accept rockets as a believable means of launching a spacecraft to the Moon, Jules Verne instead used a giant cannon in his novel From the Earth to the Moon. Verne located his cannon in Florida, only a few miles from the modern-day Kennedy Space Center. This is no coincidence. Both Verne and National Aeronautics and Space Administration (NASA) wanted a launch site close to the equator. This illustration from the original French edition of the book depicts the launch of Verne’s Moon-bound projectile.
HOW ROCKETS WORK Although rockets are associated with some of the most futuristic projects, they are one of the oldest inventions. The rocket was created more than one thousand years ago in China. The invention was probably the result of a poorly made firecracker. If the firecracker didn’t explode, it would shoot along the ground as its burning gases escaped from one end. Rockets work by the principle of reaction. The seventeenthcentury British scientist Isaac Newton explained that every action has an equal but opposite reaction. The recoil of a cannon is a familiar example of this. As the cannonball leaves the muzzle, along with the hot gases pushing it, the action of the escaping cannonball causes a reaction in the
cannon in the opposite direction, making the cannon move backward. If you blow up a toy balloon and release it, the action of the escaping air will cause a reaction in the balloon, making it fly around the room in the opposite direction of the escaping air. The recoil of a gun is another example of action and reaction. Many people believe that rockets work because their exhaust pushes against the air. But this is not true. The principle of reaction takes place within the rocket motor itself. Air, in fact, slows down a rocket by getting in the way of the gases escaping from the nozzle. The faster the gas molecules are able to go, the faster the rocket will travel. This is why rockets work best in a vacuum.
Rockets are the simplest of all motors. A fuel is burned, and the gases that are produced escape from a narrow opening. The reaction of this escaping gas causes the motor to move in the opposite direction.
Although Verne’s story used a giant cannon to launch the heroes into space instead of rockets, Verne was aware of the potential rockets had. But he was also aware of the state of the art of rocketry in the mid-1800s. His readers never would have believed that the unreliable, inefficient, and not-very-powerful rockets available at that time would ever be capable of speeding a spaceship to the Moon. Still, Verne did have his astronauts carry rockets on board. The rockets were for their eventual landing on the Moon and for steering the projectile. Verne was one of the first to realize that rockets would work in a vacuum and would be the ideal source of propulsion in space. Verne’s novel was a great success and was translated and published all over the world. It had readers and admirers in almost every nation. Some of these readers were not just admirers, they were inspired to actually do what Verne had only written about.
One of Jules Verne’s fans was a Soviet schoolteacher named Konstantin Tsiolkovsky. He was born in 1857, the son of a forester (and unsuccessful inventor) and a mother who came from a family of artisans. When he was ten, a bout with scarlet fever left him deaf. This made it difficult for him to attend school, so he studied at home. Tsiolkovsky read every book he could get his hands on, especially books about mathematics and physics. In spite of his deafness, he was offered a job as a teacher at the age of nineteen. He remained a teacher until he retired more than forty years later. In all that time, he never lost interest in science and research— especially research related to space travel.
Top: U.S. rocket pioneer Robert H. Goddard. Middle: Robert Goddard poses with the world’s first liquid-fuel rocket. Bottom: The model spaceship designed by Hermann Oberth for the 1929 science-fiction movie, Frau im Mond (The Woman in the Moon).
17 Konstantin Tsiolkovsky was a Russian schoolteacher who was fascinated by the possibility of space travel. He created much of the mathematical and theoretical foundation of modern astronautics.
THE FIRST IDEAS Tsiolkovsky realized that to propel a vehicle between planets, an ordinary motor would not work since space has no atmosphere. Steam engines and internal combustion motors all require a source of oxygen. And propellers will not work where there is no air. So it wouldn’t have done much good even if these motors did work in a vacuum. Tsiolkovsky knew that the only propulsive force that could move a vehicle in space would be the one that worked on the principle of recoil. That meant rockets, just as Jules Verne had said. Tsiolkovsky realized right away that the rocket he needed was not the ordinary gunpowder rocket. Gunpowder simply couldn’t provide enough energy to achieve the speed required for space travel. A more efficient fuel was needed. Tsiolkovsky suggested using two liquids. One liquid would be used as fuel and the other as a source of oxygen (called an oxidizer). He thought that kerosene and liquid
oxygen might work, or liquid hydrogen and liquid oxygen. Either combination would release far more energy than burning gunpowder. But the use of liquid fuels would require an entirely new type of rocket. The rocket would have to carry its fuel and oxidizer in separate containers instead of mixed together in a powder. These liquids would then be forced into an enclosed chamber, called a combustion chamber, and ignited. If one end of the chamber opened into a nozzle, the resulting blast of hot gases would propel the rocket forward. Tsiolkovsky surmised that a liquid-fuel rocket would not only be much more powerful than the old gunpowder rocket, but it could also be controlled. Because the fuel and oxidizer are fed into the motor separately, the thrust (push) of the rocket could be adjusted by allowing more or less fuel to flow into the combustion chamber. This is the same way a driver uses the gas pedal to adjust the speed
Although both liquid-fuel rockets and solid-fuel rockets are based on the same principle, they are built very differently. The solid-fuel rocket (right) contains a solid mass of fuel—a substance such a gunpowder, which combines fuel with an oxidizer. Once the fuel is ignited, it burns until it is all gone. The liquid-fuel rocket (left) carries its fuel and oxidizer in liquid form in separate tanks, so more powerful fuels can be used, and the rocket can be turned on and off.
of an automobile by forcing more or less fuel and air into the motor. A liquid-fuel rocket could even be turned off and restarted. A solidfuel (gunpowder) rocket could not. Tsiolkovsky had his first ideas about liquid-fuel rockets in 1883. He finished his first paper containing these ideas in 1898 and submitted it to a scientific journal. It was finally published in 1903. His paper not only described his new type of rocket but even considered the problems of steering in space and landing on other worlds. Unfortunately, the journal was published in Russian, a language with which few scientists outside Russia were familiar. As a result, few—if any—scientists outside the country ever read Tsiolkovsky’s theories. This lack of attention did not deter Tsiolkovsky. He persevered in his studies, producing a long series of articles—and even a science-fiction novel—outlining his ideas about rockets and space travel. Still, all of these were published in Russian and were little known to the outside world at the time he was writing.
THE SHY PROFESSOR Fortunately, Tsiolkovsky’s work did not remain ignored. In the meantime, however, several other important events occurred. Two teachers—one in the United States and the other in Romania—had also become interested in the problem of rockets and space travel. One of the teachers was Robert Hutchings Goddard, a physics professor at Clark University in Worcester, Massachusetts. The other was a shy mathematics teacher named Hermann Oberth, who lived in the mountains of Transylvania (then part of Romania). Like both Tsiolkovsky and Oberth, Goddard had been influenced by his youthful reading of the space adventures of Jules Verne and the British writer, H. G. Wells. In 1899, when Goddard was only seventeen years old, he began thinking about ways in which it might be possible to reach outer space.
Robert H. Goddard (left) designed and built the first successful liquid-fuel rocket. Here he is seen at work on one of the rockets he built in the 1930s.
In 1919 Robert Goddard published a short booklet called A Method of Reaching Extreme Altitudes. In his first sentence, Goddard explained why he decided to write the booklet. It was a result of his search for a method of sending scientific recording instruments to heights beyond those attainable by balloons—that is, higher than 20 miles (32 km). He concluded that only a rocket would be able to do this. At the end of the booklet, almost as an afterthought, Goddard suggested that it might be possible for a rocket to actually carry a payload—cargo carried by a rocket—to the Moon. He speculated that a rocket could perhaps carry a quantity of flash powder (a powder containing magnesium that photographers once used to take flash pictures). Astronomers on Earth could see the flash when the powder exploded on impact.
Goddard came to regret that he made this prediction. Although Tsiolkovsky’s remarkable theories were largely ignored, Goddard’s little booklet immediately became the subject of headlines from coast to coast. Newspapers might have overlooked the idea of using rockets to explore the upper atmosphere. But the idea of sending a rocket to the Moon was another matter entirely! Newspapers around the country seized on Goddard’s remark. The quiet, shy professor of physics found himself the subject of headlines. “Modern Jules Verne Invents Rocket to Reach the Moon,” shouted the Boston American. “Claim Moon Will Soon Be Reached,” blazoned the Milwaukee Sentinel. “Savant Invents Rocket Which Will Reach Moon” declared Popular Science magazine. Of course, Goddard had done nothing of the kind. He had only suggested that a rocket might someday reach the Moon. Goddard even received a request from a Hollywood studio asking if he would include a message from a popular film star in his rocket. The worst blow came from the New York Times. Following the headline, “Believes Rocket Can Reach the Moon,” was an editorial that claimed that Goddard was simply ignorant of the basic laws of physics. Goddard’s rocket, the writer asserted, would not work. “That Professor Goddard . . . does not know the relation of action to reaction, and of the need to have something better than a vacuum against which to react—to say that would be absurd. Of course, he only seems to lack the knowledge ladled out daily in high schools.” (The Times publicly apologized for this statement in 1969.) These criticisms stung Goddard deeply. He was especially upset by the accusation that he was making a fundamental error in physics. The idea that a rocket flew by pushing against the air behind it was a common one that even many scientists—who should have known better—believed. Rather than helping make a rocket go, the
presence of air actually slows it down. A rocket will not only work in a vacuum—as both Jules Verne and Goddard knew well—it works better in a vacuum. This public humiliation caused Goddard to retreat behind a wall of secrecy. Few people after that learned about the work he was doing. This decision had some serious consequences regarding the future development of spaceflight.
GODDARD’S TRIUMPH Although Goddard had written about solid-fuel rockets in his booklet, he began considering the potential of liquid fuels. Unlike Tsiolkovsky, who was a pure theoretician and never actually built any of the liquidfuel rockets he wrote about, Goddard was experienced in the art of creating machinery. He wanted to design, build, and fly a liquid-fuel rocket. Because of his practical experience, Goddard realized what a difficult task this would be. A solid-fuel rocket is simple to build. But a liquid-fuel rocket requires special tanks for its fuel and oxidizer. It also has to have pumps, motors to run the pumps, methods of cooling the motor, and lots and lots of plumbing. After several years of experiments and tests, Goddard finally had a liquid-fuel rocket that he believed was ready for flight. What he had built, though, would hardly be recognizable as a modern rocket. It was little more than a fragile-looking framework of thin pipes connecting the fuel and oxidizer tanks with the motor itself. On March 16, 1926, Goddard took his rocket and its launching frame to an open snowy field on a farm owned by one of his relatives. His wife and two men from Clark University accompanied him. Launching the rocket was simple. The fuel and oxidizer valves were opened while one of the men, holding a blowtorch attached to
a short pole, held the flame under the rocket’s nozzle. The motor erupted with a shrill roar, and the rocket lifted from its frame. After only two and a half seconds, the rocket dropped back to the ground, its fuel exhausted. It had traveled a distance of 184 feet (56 m) and achieved a speed of about 60 miles (97 km) per hour. This is unimpressive even by the standards of a small gunpowder skyrocket. But it was the flight of the world’s first liquid-fuel rocket.
THE THIRD FOUNDER Meanwhile, Hermann Oberth had been working on the mathematical and theoretical basis of spaceflight. As a boy, he had long been fascinated by the space travel stories of Jules Verne and Kurd Lasswitz, a German science-fiction writer. In 1925, at the age of twenty-nine, Oberth published a slim book called Die Rakete zu den Planetenräumen (The Rocket into Planetary Space). In the book, he discussed the possibilities of rocket flight into space in more detail than anyone had ever done before. In the spring of that year, Oberth was shocked to read in a newspaper about Robert Goddard’s booklet. He had no idea that anyone else in the world had been thinking about the same subject. Oberth tried in vain to locate a copy of the booklet in the German city of Heidelberg. He finally wrote to Goddard, who promptly sent him a copy. When the booklet arrived, Oberth read it eagerly. He was amazed by Goddard’s ideas and calculations. But he also realized that Goddard had not gone nearly as far in his thinking as he had. Goddard had only suggested a small, unmanned, solid-fuel rocket that might carry an explosive charge to the Moon. Oberth, on the other hand, had realized that liquid fuels—such as gasoline and liquid oxygen—could provide twice the exhaust velocity of any powder.
As a result, the rocket could go twice as fast. He concluded that the conquest of space could be accomplished only with liquidfuel rockets. By the time Oberth read Goddard’s 1919 booklet, Goddard himself had arrived at the same conclusion. But he had also begun building a liquidfuel rocket. Of course, Oberth Hermann Oberth (above) was a
didn’t know this, especially
young schoolteacher, still in his
since Goddard kept his work
twenties, when he published his book Die Rakete zu den Planetenräumen. His book was the first detailed
secret. Oberth’s little book didn’t
mathematical analysis on the
initially sell well. This was
possibility of space travel.
mostly because Oberth’s mathematical calculations were very
complex, and his writing style was quite technical. In fact, the publisher was so reluctant to publish the book that Oberth had to pay most of the printing costs. A writer of popular science articles named Max Valier, however, recognized the importance of Oberth’s claims. Valier published a book explaining the ideas in simpler terms. The twenty-nine-year-old Oberth was amazed to discover that he had become an overnight sensation. His ideas quickly spread throughout Germany and, finally, the rest of the world. They proved that a liquid-fuel rocket was possible and that it was the key to successful spaceflight. The publisher of Oberth’s original book was astonished when the book had to be reprinted in an expanded edition.
PUBLICITY When Oberth began writing, no one, as far as he knew, had ever built a liquid-fuel rocket. The only rockets familiar to anyone were ordinary fireworks rockets. Even the few rockets still used by the military were not much different. But a big difference existed between those rockets and the kind of rockets that Oberth proposed. For one thing, a solidfuel gunpowder rocket never moves very quickly. Almost immediately after its supply of fuel runs out, the rocket falls back to the ground. A liquid-fuel rocket, on the other hand, is capable of achieving tremendous speed. So much so that when its fuel runs out, it could keep going. It could go perhaps many times farther than it had traveled while powered by the fuel. Historian Willy Ley described the effect in this way. When a liquid-fuel rocket is powered, say, for the first mile of its flight, it is as though it were a projectile in a gun 1 mile (1.6 km) long. The bullet from a gun will keep going for a long distance after it leaves the muzzle of the gun. In the same way, the rocket will also keep going for a long distance after its fuel is exhausted. Oberth knew that liquid-fuel rockets were capable of reaching much greater distances than anyone had previously suspected. But Oberth went even further than proving the mathematical possibility of the liquid-fuel rocket. In the second part of his book, he outlined the characteristics of just what a high-altitude, instrument-carrying rocket would be like. In the third part, he described a manned spaceship in such detail that his readers thought they could go out and build one just by following his instructions. In fact, one man very nearly did. Filmmaker Fritz Lang was the George Lucas or Steven Spielberg of his time. He had made some of the biggest, most amazing science-fiction and fantasy movies of all time, such as the classic Metropolis. He wanted to produce the
greatest movie ever made about space travel and asked Oberth to be its technical adviser. The shy young man reluctantly agreed. The result, Frau im Mond (The Woman in the Moon, 1929), was an odd mixture of great science and sheer fantasy. (For example, the movie’s astronauts discover air on the Moon, when scientists had known for at least a hundred years that the Moon is airless.) But the movie really shines in its depiction of the construction and launching of a giant manned rocket. Entirely Hermann Oberth designed the spaceship for the classic 1929
based on Oberth’s designs, the
science-fiction film Frau im Mond,
Friede is a giant, two-stage (two-
basing it on the giant two-stage,
part) rocket. The rocket is rolled
liquid-fuel rocket in his book. This
out of a huge vehicle assembly
photo shows the model used in the movie.
building, just like the modern space shuttle. The film even in-
cluded the world’s first countdown to a space launch. The movie’s special effects were excellent, and the overall realism of the movie made it an inspiration for many young rocketeers. In fact, the movie may have even been too realistic. It is said that at the beginning of World War II (1939–1945), the Nazis seized the model spaceship used in the film. They thought it gave away too many technical secrets!
MULTISTAGE ROCKETS As a rocket travels, its fuel and oxidizer tanks empty. Since the empty tanks are of no use, their extra weight only serves to slow down the rocket. If it were possible to cut away the empty part of the fuel tanks as they drain, the rocket would be lighter and could go higher and faster. This is what happens in a staged rocket. But instead of literally cutting away the empty parts of a rocket, engineers stack one rocket on top of another. Each rocket is called a stage. In a multistage rocket, the first stage is the largest. It must lift
itself, as well as all the stages above it, from Earth’s surface. Once its fuel and oxidizer are used up, the first stage falls away and the next stage can start its engines. The second stage can be smaller than the first one because it only has to lift itself and the stages it carries. And as before, once its fuel and oxidizer are used up, it can be cast off. Each time an empty stage is dumped, the rocket becomes lighter and can go higher and faster. Stages can be stacked one atop the other or they can be mounted side by side, as on the space shuttle.
A multistage rocket can go faster— and eventually farther—than an ordinary rocket because it discards empty fuel tanks as it goes. By not having to carry such dead weight, it continues to gain speed.
THE ROCKET RIDERS
Almost from the time the rocket had been invented, people had wondered if it might be possible to ride one. A legend says that around the year 1500 a Chinese official named Wan Hoo (whose name might be loosely translated as “Crazy Fox”) was the first person to attempt a manned rocket flight. He fitted a chair with a pair of winglike kites and forty-seven powder rockets. At a prearranged signal, forty-seven servants with matches touched off all forty-seven rockets. Wan Hoo vanished with a brilliant flash and a cloud of smoke, reaching the heavens a little more suddenly than he had perhaps intended.
Top: Test launch of a German V-2 rocket during World War II. Middle: The first U.S. aircraft to take off under rocket power was this Ercoupe flown by Herman Boushey in 1941. Bottom: In 1958 the Russian dog Laika was the first living creature to travel in space when she flew in Sputnik 2.
According to legend, a Chinese official named Wan Hoo (left) tried to reach heaven by attaching rockets to his throne, as shown in this modern Chinese illustration.
Three hundred years later, around 1828, Claude Ruggieri was the royal pyrotechnician (fireworks expert) of France. He began experimenting with launching live animals in rockets, returning them unharmed to the ground by parachutes. After successful experiments with mice and rats, he announced his plans to build a giant combination rocket that would carry a full-size ram aloft. Immediately after this announcement, Ruggieri received an offer from a young man who volunteered to take the place of the animal. A date for the big event was advertised, but the police forbade the experiment.
Claude Ruggieri, the famous French fireworks designer, tried to launch a young man in a rocket. He was prevented from doing so at the last minute by the Paris police, as shown in this modern illustration of the event.
The first documented flight of a human being in a rocket-propelled vehicle took place in Germany in 1928. It was the result of a collaboration among rocketry enthusiast Max Valier, rocket manufacturer Friedrich Sander, and auto manufacturer Fritz von Opel, who financed the experiment. A glider called the Ente (Duck) was specially adapted to carry Sander’s solid-fuel rockets. After several tests, pilot Friedrich Stamer took off under the power of a single rocket motor (with the aid of a rubber rope catapult). After flying about 650 feet (198 m), the rocket burned out, and Stamer fired a second one. This propelled the Ente another 1,640 feet (500 m). The second rocket burned out, and Stamer landed after a total flight of about 4,900 feet (1,494 m). He became the first human being to fly in a rocket-propelled vehicle.
The first human being to make a documented attempt to fly in a rocket was F. Rodman Law. Law was a notorious daredevil and brother of Ruth Law, a famous aviator. In 1913 Rodman Law had a fireworks factory build an enormous skyrocket, supposedly for a movie. It was a sheet-metal cylinder 10 feet (3 m) long and 3 feet (0.9 m) in diameter. On top of this was a cardboard tube surrounding a chair in which Law sat. On top of everything was a cardboard nose cone. Attached to the side of the cylinder was a stick nearly 20 feet (6 m) long and 4 inches (10 centimeters) in diameter. Looking exactly like an enormous Fourth of July skyrocket, the entire thing was held upright in a wooden scaffold. Law’s plan was to launch himself 3,500 feet (1,067 m) into the sky. He would descend by means of a parachute. He would take off from Jersey City, New Jersey, and he hoped to Stuntman Rodman Law attempted to be the first person to ever fly in a rocket. Here he is seen climbing into the top of his enormous rocket. Unfortunately, instead of zooming high into the air, the rocket disintegrated in a tremendous explosion, injuring Law badly.
EFFORT land in Elizabeth, New Jersey— about 12 miles (19 km) away. As 150 people watched, the manager of the International Fireworks Company—which had made the rocket—lit the fuse. According to a newspaper report, the fuse “spluttered for some time. Then followed a terrific explosion. . . . Law fell like a sack to the ground.” He was taken to a hospital where he announced his intention to make another attempt at a rocket flight. There is no record of him ever doing so.
This is an artist’s depiction of the 1928 flight of the Ente, the first successful rocket-powered, piloted aircraft in history. Soon after this flight, a large number of experimenters in Europe began building and flying rocket-propelled aircraft, some eventually using liquid-fuel rockets.
Many other enthusiasts followed Stamer’s feat with rocket plane flights of their own. Later, rocket-propelled fighters were developed by the Germans during World War II. The Germans did test flights of the Heinkel-176, the first liquid-fuel rocket aircraft, in 1939. In 1941 the batlike Messerschmidt Me-163 rocket plane made its first powered flight. Pilot Heini Dittmar reached a speed of nearly 624 miles (1,004 km) per hour. It was the first aircraft to exceed 621 miles (1,000 km) per hour—more than 80 percent of the speed of sound (761 mph [1,225 km/h] at sea level). On a second flight that day, champion German glider pilot Hanna Reitsch achieved a speed of 624 miles (1,004 km). Hanna Reitsch was the first woman to fly a jetpropelled aircraft. She was also the first to fly a rocket. Reitsch test-flew the rocket-propelled Me-163 Komet. She made numerous powered takeoffs and sometimes went nearly as fast as the speed of sound. Reitsch is not only the first woman in the world to fly a rocket plane, she is the only one to date. While these rocket-powered aircraft were not actually spacecraft, they helped prove that rockets were practical for propelling human-
piloted vehicles. They showed that humans could withstand the great acceleration and speed of rockets. They tested techniques for flying at high speeds and the effect these speeds had on different materials. These early rocket planes were the ancestors of the rocket-propelled aircraft that led directly to the development of manned spacecraft.
THE V-2 During World War II, Germany also produced the huge V-2 rocket. Wernher von Braun, a young engineer who had been interested in rocketry and spaceflight since
The first rocket-propelled aircraft that was successfully flown in the United States was William Swan’s
childhood, developed it. The
Steel Pier Rocket Glider (top),
Germans intended to use the V-2
which flew in 1934. Powered by
as a weapon, but von Braun knew
twelve solid-fuel rockets, the
that the rocket was also capable
glider reached an altitude of 200 feet (61 m).The Messerschmidt
of reaching outer space. The V-2 was the biggest rocket anyone had attempted to build up to that time. It stood 46
Me-163 Komet (above) was the only operational rocket-powered fighter aircraft during the Second World War.
feet (14 m) tall and weighed 10,000 pounds (4,536 kg) fully fueled and ready for launch. By comparison, Robert Goddard’s first liquid-fuel rocket, which had been launched just sixteen years before the first V-2 launch, stood only 10
feet (3 m) tall. It weighed just a little over 10 pounds (4.7 kg) at takeoff. Many scientists were aware that the V-2 might be capable of reaching outer space. Knowing that the rocket could carry about 1 ton (1 metric ton) of explosives, German rocket expert Willy Ley suggested that the explosives be substituted by a pilot. Together with a protective suit, a pilot might weigh only 300 pounds (136 kg). The difference would be made up by extra fuel. If something even as simple as that could
Wernher von Braun holds a
be done, Ley said, the rocket
model of the V-2 rocket he
might be able to reach the fringes
of outer space. Von Braun and Ley were proven right in 1942. During a test flight, a V-2 rocket reached an altitude of 117 miles (188 km). It was only the very fringe of outer space, but the V-2 proved it could be done.
Meanwhile, U.S. scientists had little interest in developing largescale rocket weapons like the V-2. Instead, they were trying to develop a rocket-propelled fighter of their own. In the United States, the aircraft company Northrop developed the XP-79, a rocket-powered flying wing. After several years of tests, the resulting rocket plane, the MX-324, made its first flight on July 5, 1944.
THE AMERICA BOMBER AND THE SILVER BIRD During World War II, Germany devised two schemes to bomb the United States. Both involved rockets. The first was the so-called America Bomber. This would have required a piloted, winged V-2 rocket called the A-9 boosted by a huge rocket called the A-10. The winged rocket would fly to an altitude of 210 miles (338 km)— about the height at which the space shuttle orbits. It would carry a payload of about 1 ton (1 metric ton) 3,000 miles (4,828 km). While a few A-9s were built and tested in wind tunnels, none was ever flown. Meanwhile, an even more daring scheme was being developed by the research team of Eugen Sänger and Irene Bredt. Their idea was to construct an Earth-orbiting, single-stage rocket plane capable of taking off from Germany, delivering a bomb while over the United
The Sänger spaceplane, shown here in an artist’s depiction, was designed to drop a bomb on New York City. Launched from Germany, it would have skipped across the upper layers of Earth’s atmosphere like a stone skipping across a pond.
States, and returning to its takeoff point. The 100-ton (91 metric tons) spacecraft would have a liquidfuel motor that would boost the Silbervogel (Silver Bird) to an altitude of 186 miles (300 km) with a payload of 4 tons (4 metric tons). Like the America Bomber, the Sänger spaceplane would skip across the upper layers of the atmosphere. The Silver Bird would have been a beautiful vehicle: sleek and bulletshaped with a flat undersurface. It would have had stubby, knifeedged wings and a small tail. Researchers conducted many tests with wind-tunnel models, but the entire project never got off the ground. The efforts of Sänger and Bredt weren’t wasted, however. Much of their research helped in the early development of later spaceplanes such as the X-15 and the space shuttle.
Its liquid-fuel engine was not powerful enough to enable the little aircraft to take off under its own power, so it had to be towed aloft by another airThe experimental MX-324 was the
plane. After the MX-324 was re-
United States’ first purpose-built
leased by the other plane, test
rocket fighter. It never saw service
pilot Harry Crosby flew under
but did provide a great deal of valuable engineering data.
rocket power for four minutes. It was the first liquid-fuel rocketpowered aircraft to fly in the United States. After the war, research in rocket-powered aircraft continued. Scientists were interested in studying the effects of flying at very high speeds, especially at or beyond the speed of
The main difference between jets and rockets is the source of oxygen. Jets consume oxygen from
sound. Even though jet propulsion had made great advances
the atmosphere, which means that
during the war, rockets still
they cannot fly into space, where
seemed to be the best way to
there is no atmosphere. Rockets,
achieve the speeds required.
on the other hand, carry their own supply of oxygen and can travel in the vacuum of space.
In 1947 the Bell X-1 rocket plane carried pilot Chuck Yeager to 700 miles
(1,127 km) per hour—Mach 1.06. (Mach 1 is the speed of sound at sea level.) Dubbed Glamorous Glennis by Yeager, the tiny aircraft had been patterned after a .50-caliber bullet. It had been in development for two years as a cooperative project between the U.S.
JATO Rockets were used extensively during World War II to help boost aircraft that were overloaded, had to take off from runways that were too short, or both. These rockets were usually solid-fuel motors that were attached to the exterior of the plane and could be discarded after takeoff. These rocket motor units are called JATO (JetAssisted Take Off). The California Institute of Technology, along with AerojetGeneral founder Theodore von
Kármán, developed JATO units in the United States. A commercially manufactured light plane was fitted with six solid-fuel rockets. On the first trial, pilot Herman Boushey took off under the plane’s own power, using the rockets only as a booster. Later, he took off and flew using rocket power only, making him the first American to fly a rocket-propelled plane since William Swan in 1934 and the first to fly a rocket plane that took off under its own power.
Air Force and the National Advisory Committee for Aeronautics (NACA, NASA’s predecessor). The X-1 was built of high-strength
and powered by a 6,000pound-thrust (2,722 kg) liquid-fuel motor. It was not allowed to take off on its own from the ground, primarily for safety reasons. It had to be carried aloft in the bomb bay of a B-29 (and later a B-50).
Test pilot Chuck Yeager (right) poses with fellow officers in front of the Bell X-1, the tiny rocket plane that broke the sound barrier.
(Captain Yeager did make a ground-level takeoff in 1949.) The top speed ever achieved by the X-1 was Mach 1.45—approximately 957 miles (1,540 km) per hour.
The entire idea of spaceflight got a tremendous boost—literally—by the launch of the first successful rocket in the U.S. Army’s Project Bumper series. The project consisted of a captured V-2 rocket with a smaller WAC-Corporal rocket placed in its nose. When the larger rocket reached its maximum altitude, the WAC-Corporal was fired. This was the United States’ first two-stage liquid-fuel rocket and perhaps the first one in the world. On February 24, 1949, a WAC-Corporal reached a record altitude of 244 miles (393 km). It was the first artificial object to reach outer space.
The first launch of Project Bumper, in which a captured German V-2 rocket is carrying a smaller WACCorporal in its nose, took place in 1949. When the V-2 reached its maximum altitude, the smaller rocket launched, adding its speed to that already gained by the V-2.
Everything that was needed to put a human being into space— either via a suborbital “hop,” such as the WAC-Corporal had made, or into Earth orbit—was ready. The techniques, engineering, materials, and fuels were all available. No serious technical obstacles remained. But even the simplest spaceflight would probably cost billions of dollars. Only a national government had the resources to undertake such a project.
In 1953 NACA began developing the world's first spaceship. The goal of NACA’s program was to develop an aircraft that could explore the problems of upper-atmospheric and near-space flight. For instance, how would the pilot control the craft? What would the pilot’s physical reactions be to flying at such great altitudes? The flights would be done at speeds of Mach 6.6 and higher and at altitudes of 12 to 50 miles (19 to 80 km). The result of NACA’s program was the development of the X-15, one of the most successful research rocket planes ever flown. The X-15 was a slender, black, 50-foot (15 m) rocket plane. It had stubby, knife-edged wings and control surfaces for atmospheric flight, like those on ordinary planes. But there would be too little air to use normal wing and tail controls at the highest altitude it was expected to reach. Therefore, the X-15 also had nose and wingtip thrusters so it could be maneuvered in the fringes of space. (The X-15’s resemblance to the Sänger Silver Bird was no accident. The German team’s research had a huge influence on the X-15’s designers.) The X-15 was so similar to a spaceship that its pilot was required to wear a full-pressure space suit. In fact, many X-15 pilots were given astronaut status since the maximum altitude reached by the plane was more than 67 miles (108 km). This altitude was well
beyond the official threshold of space. At one point, NACA scientists considered mounting an X-15 on top of a large booster rocket and launching it into Earth orbit. Of the three X-15s built, two had long service lives. They made a total of 199 successful flights. In the process, they provided enormous quantities of data vital to the fledgling U.S. space program.
After losing World War II, Germany lost some of its top rocket scientists to the United States. Chief among these was Wernher von Braun, who had been in charge of the V-2 project. Von Braun was an engineering genius who probably knew as much or more about rockets than any other person at the time. He was also a great visionary who had always kept his eyes on one major goal: the development of space travel. Von Braun was a compelling speaker who easily conveyed his enthusiasm for space travel. He was also a skilled writer who had a talent for explaining technical details in terms anyone could understand. Through appearances on television and a long series of influential illustrated magazine articles, von Braun began to convince the American people that space travel was not a fantasy. Much as Jules Verne had done a century earlier, he demonstrated that it could be accomplished by means of existing technology. The only thing missing was the commitment. As a result, more and more pressure was put upon the U.S. Congress to fund a full-scale space program. But the government still dragged its feet. That is, until October 4, 1957. On that day, the Soviet Union placed the first artificial satellite, Sputnik 1, into orbit around Earth. U.S. politicians were stunned by this news, although they shouldn’t have been. Many scientists had been trying to warn the
government that the Soviets were on the verge of spaceflight. But the United States was still basking in the glow of its victory in World War II. U.S. leaders were convinced that only the United States had even a marginal chance of launching a spacecraft into orbit. To make things worse, the Soviet Union was a dictatorship and an enemy. U.S. leaders had been telling citizens that such a nation just wasn’t capable of achieving anything before a free democratic country. The United States immediately started a program to get a satellite into orbit as soon as possible. A satellite launcher called Vanguard had many embarrassing failures. (Unlike the Soviet Union, which publicized only its successes, the United States televised its launches—and failed launches—for the whole world to see.) After the Vanguard’s failures, von Braun received approval to do what he had wanted to do all along. He could assemble a satellite launcher from the existing, well-proven rockets he had been helping the army develop. In the meantime, Russia launched a second satellite, Sputnik 2. This satellite carried a dog named Laika into orbit. Finally, on January 31, 1958, the United States launched its first artificial satellite, Explorer 1, into orbit. At 31 pounds (14 kg), it was tiny compared to the Soviet satellites. Sputnik 1 weighed 184 pounds (83 kg), and Sputnik 2 weighed 1,120 pounds (508 kg). Even so, Explorer 1 was a source of immense national pride and relief. But the United States’ joy was short lived. On April 12, 1961, the Soviet Union launched the first human being into space. He was a young pilot named Yuri Gagarin. Gagarin made one circuit of Earth in his Vostok (East) capsule. The Soviets cheered and gloated while the Americans swore that they would never again be upstaged. The rivals began a full-scale space race.
FIRST STEPS TOWARD THE MOON
In 1958, a year after the success of the first Soviet satellite, U.S. president Dwight Eisenhower signed an act creating NASA. It had the task of developing a civilian space program. In December of that same year, NASA announced that its official manned space program would be called Project Mercury. The project had two goals. First, it was to investigate the ability of humans to survive and work in the environment of space. Second, it was to develop and test the basic hardware for future manned spaceflight programs. In 1961 President John F. Kennedy told Congress, “I believe this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to Earth.” Kennedy’s announcement spurred the nation to create a systematic, step-by-step program that
Top: An Atlas rocket takes off, carrying U.S. astronaut John Glenn into space. Middle: Ed
would end with a lunar landing. Project
White takes the first space walk
Mercury became the opening act for the
by a U.S. astronaut. Bottom:
new lunar landing program, which was to
The Titan rocket carrying
be called Apollo. For all the scientific and human value of manned spaceflight programs,
Gemini 12 and its astronauts takes off on November 11, 1966.
Left: Alan Shepard is lifted from his capsule by a helicopter after a safe landing in the Atlantic Ocean following his historic ride into space. Right: The United States’ original seven astronauts (front row, left to right) Walter Schirra, Donald Slayton, John Glenn, Scott Carpenter (back row, left to right), Alan Shepard, Virgil Grissom, and Gordon Cooper.
the decision to go to the Moon was basically a political one. The United States had been nursing the bruises it had received from the Soviet Union’s unexpected advances in space. Evidence existed that the Soviets were gearing up for a lunar landing mission. The Americans simply would not let them get there first.
The Soviet Union had already beaten the United States in the race to launch a person into space. But less than a month later, on May 5, 1961, NASA launched Alan Shepard Jr. into space aboard the Mercury 3 capsule. Unlike Gagarin’s orbital flight, Shepard’s was suborbital. Instead of going into orbit, the capsule simply followed a curved path, rising into space and then dropping back toward Earth, like that of a bullet
THE PRICE The United States underwent a great deal of international criticism about the slow, methodical pace at which it was undertaking its manned space program. But it turned out that it had taken the right course. Decades after the first manned spaceflights, U.S. scientists learned that the Soviets had taken many shortcuts in their haste to get a man into orbit as soon as possible. Some of these shortcuts had proven fatal. At least four
cosmonauts (Soviet astronauts) died during the reentry of their spacecraft from orbit. The intense secrecy of the Soviet government, which controlled the news with an iron fist, kept these tragic failures from becoming widely known to Soviet citizens and the rest of the world. By contrast, between the start of the Mercury program and the Challenger space shuttle disaster on January 28, 1986, three U.S. astronauts were killed.
shot from a gun. In August Soviet cosmonaut Gherman Titov spent just over a full day in space, orbiting Earth seventeen times before returning. On February 20, 1962, the United States finally succeeded in placing a human in orbit. John Glenn Jr. circled Earth three times in his Mercury 6 capsule. Mercury capsules had a retrorocket pack strapped to their large, curved heat shields. These rockJohn Glenn squeezes himself through the narrow hatch of his Mercury capsule, named
ets were fired to slow the capsules for their return to Earth. Once the rockets
Friendship 7, just before he
were fired, the packs would be thrown
was launched into space on
off to leave the heat shield clear for
February 20, 1962.
reentering Earth’s atmosphere.
THE MERCURY SPACECRAFT The Mercury capsule, the United States’ first manned spacecraft, was barely large enough to contain the single astronaut it carried. It was a cone only 6.2 feet (1.9 m) at its widest point. It had a curved heat shield at its base— which would prevent the capsule from burning up on reentry—and a kind of tower on top. At the top of the tower was a solidfuel rocket motor with three nozzles. This motor was designed to carry the capsule away from its booster in case an emergency occurred at takeoff. Between the base of the tower and the top of the capsule was the cylindrical parachute container. The astronaut could adjust the attitude of
the capsule (the angle by which it was oriented to Earth) by using small thrusters located on the sides and top of the capsule. Beneath the heat shield was a cylindrical retrorocket pack. These rockets slowed down the capsule for reentry from orbit. The pack was thrown away just before reentry to leave the heat shield clear. Mercury capsules—like all U.S. spacecraft until the space shuttle—were recovered at sea. As the capsule’s parachute lowered it near the surface of the water, the heat shield was dumped and a landing bag was deployed from the base of the capsule. This served as a collapsible air cushion to soften the shock of impact. The capsule itself had enough buoyancy to float upright.
The small size of the Mercury space capsule is evident in this photo of a technician working on final assembly details in the early 1960s.
But Glenn’s ground crew received a signal that the heat shield on his capsule had come loose. If it were to come off during reentry, the capsule would burn up like a meteor from friction with Earth’s atmosphere. The ground crew decided to keep the retrorocket pack attached, hoping that its straps would help keep the heat shield in place. No one was sure what would happen during reentry. Would the disintegrating retrorocket pack damage the capsule? Would the pack tear away the heat shield entirely? Fortunately, the plan worked. Even though Glenn reported seeing flaming chunks of the retrorocket pack flying past his window, he made a successful return to Earth.
THE COMPETITION INCREASES For the next several years, spaceflight firsts bounced from one nation to the other. On May 24, 1962, U.S. astronaut Scott Carpenter made three orbits of Earth in his Aurora 7 Mercury capsule. Three months later, cosmonaut Andrian Nikolayev made sixtyfour orbits in a mission lasting more than ninety-four hours. More U.S. and Soviet flights were made, each adding more and more orbits. Then, in June 1963, the Soviets placed the first woman, Valentina Tereshkova, into orbit. (NASA had barred Russian cosmonaut Valentina
women from spaceflight training
Tereshkova was the first woman to
until 1978. So the United States
fly into space on June 16, 1963.
did not match this feat until 1983.)
The Soviets continued to set the bar ever higher for the Americans by launching the first multiple-person crews into orbit. Voskhod 1 carried three cosmonauts in 1964. This was followed soon after by the two-person Voskhod
Belyayev and Alexei Leonov. During their twenty-six hours in orbit, Leonov sealed his space suit, opened a hatch, and left the spacecraft. For ten minutes, he floated in space, attached to the spacecraft only by a 5-foot (1.5 m) tether, making the first space walk in history. One thing Leonov hadn’t counted on, though, was the fact that his space suit would expand in space like a balloon because of the air pressure inside it. When he tried to get back into the spacecraft, he was too big to fit through
Three frames of motion picture film show cosmonaut Alexei Leonov floating in space outside
the hatch. The only solution was
his capsule on March 18, 1965—
to release some of the air in his
the first human being in history
suit, deflating it enough for him to
to do so.
get through the hatch. Opening his space suit in the vacuum of space must have taken enormous courage since even a few seconds of exposure might have been fatal.
SPACE SUITS Human beings can’t survive in space unprotected. If astronauts want to leave the safety of their spaceship, they have to be provided with several essential things. First, they have to have air to breathe—a mixture of oxygen and other gases, such as those that make up Earth’s atmosphere. Astronauts also need some sort of pressure over their body. Without it, their blood would boil at their own body temperature. As air pressure decreases, the temperature necessary to boil water and blood also decreases. People who live at high altitudes, where air pressure is lower, have to boil water longer in order for food to cook. The lower air pressure means that water boils at a lower temperature. If air pressure is low enough, water will boil at 98.6°F (37°C)—the average temperature of the human body—instead of 212°F (100°C).
Pressure in most space suits is achieved by inflating them, just as you would inflate an inner tube. Fortunately, it’s not necessary to use the full 14 pounds per square inch (0.98 kg/cm2) of Earth’s normal pressure at sea level. Otherwise, the suit would blow up, becoming too stiff and rigid for astronauts to be able to bend their arms, legs, and fingers. Even at a fraction of that pressure, flexing a space suit’s arms and legs would be difficult if it wasn’t equipped with special joints. A method to get rid of excess heat is necessary too. This might seem strange because space is often thought of as being very cold. In reality, space has no temperature at all. It is a vacuum. Have you ever kept coffee or soup hot in a thermos bottle? The reason a thermos can do this is because there is a vacuum between the inner bottle and the outer one.
PROJECT GEMINI Project Gemini followed NASA’s Mercury program. Although the Gemini spacecraft looked like the Mercury spacecraft, it was more technologically advanced, much larger, and carried two astronauts (hence the project name, Gemini—the constellation of the twins). The goal of the program was to test the effects of long-term spaceflight, extravehicular
Astronaut Alan Shepard relaxes for a moment as a technician helps him with his space suit.
The only way for heat to pass through a vacuum is by radiation, and that happens very slowly. Space is the same way. Astronauts are surrounded by a vacuum, just like the coffee in the thermos, so they have no way to get rid of their body heat. They might cook inside their suits if the suits were not equipped with a cooling system.
If astronauts have to work outside their ship, they might have to use some sort of handheld thruster or perhaps a backpack equipped with thrusters. Thrusters allow them to move around in space independently, just as though they were their own spaceship. In fact, a space suit really is a kind of wearable spaceship.
activities (EVAs), orbital maneuvering, and rendezvous and docking techniques. These skills would be essential for a future mission to the Moon. The first Gemini flight took place on March 23, 1965, when U.S. astronauts Virgil Grissom and John Young rode Gemini 3 into orbit. Although the mission lasted only four hours, the astronauts still had time to perform several scientific experiments.
THE GEMINI SPACECRAFT The Gemini spacecraft looked similar to the earlier Mercury capsule. It was much larger, however, and much more sophisticated. Carrying a two-person crew, it consisted of two main components: the cone-shaped spacecraft and a large equipment module attached to its base.
itself. (This gave the astronauts much more room.) The lifesupport system not only provided the astronauts with breathable air but removed impurities and maintained the temperature of the spacecraft. The equipment module was discarded before reentry.
The equipment module contained all the electronic equipment, as well as fuel cells for generating power. It also held life support that could withstand the vacuum of space and didn’t need to be contained in the capsule
The spacecraft itself was 11 feet (3.4 m) long and 7.5 feet (2.3 m) wide at its base. A cylinder at the nose of the capsule contained the recovery parachute, as well as the equipment needed for docking.
An astronaut in another nearby Gemini capsule took this photo of a Gemini spacecraft. Although the Gemini spacecraft superficially resembled the Mercury capsule, it was actually quite different. Gemini was roomy enough to carry two astronauts. The large white section contained oxygen, life support, batteries, and other equipment. This section was discarded before the spacecraft began reentry into Earth’s atmosphere.
During the mission, Young presented Grissom with a corned beef sandwich he had smuggled on board. Astronauts’ diets were strictly regulated. More important, food needed to be kept contained within tubes and packets. This prevented crumbs and other debris from potentially getting into the spacecraft’s electrical and life-support systems and causing problems. (The spacecraft’s air filters were not designed to handle crumbs.) Corned beef sandwiches are messy, and NASA officials were not amused by the stunt. Eventually, twelve Gemini missions launched before the program was completed in 1966. These missions included the first U.S. space walk and the first-ever use of a device that allowed an astronaut to maneuver while outside the spacecraft. The device was a small, handheld gunlike tool that released jets of compressed gas. For more than twenty minutes, astronaut Ed White flew independently of his Gemini 4 capsule, becoming a spaceship in his own right. Astronaut Ed White of Gemini 4 was the first American to perform a space walk. Tied to a tether, White floated in space for twenty-two minutes. He used a special “gun” that ejected jets of gas and enabled him to maneuver like a human rocket.
LEARNING NEW SKILLS Gemini astronauts also practiced rendezvousing (coming together at a specific time and place) with another spacecraft. Orbit rendezvous between two spacecraft was going to be an essential part of the Apollo program, which was still in the planning stages. NASA had decided to use the Lunar Orbit Rendezvous method for its upcoming lunar landing. In this plan, the main spacecraft would act as a kind of “ferry” for the lunar lander. To practice these techniques, Gemini spacecraft rendezvoused with each other, although the spacecraft were incapable of docking (joining mechanically). On December 4, 1965, Gemini 6 rendezvoused with Gemini 7. The two spacecraft maneuvered so closely that the astronauts in each spacecraft could wave to one another. During the course of the mission, Gemini 7 also made the longest spaceflight up to that time: more than 330 hours. The Gemini 8 astronauts were launched into space on March 16, 1966. To practice both rendezvousing and docking, an Atlas multistage rocket had previously boosted an unmanned Agena stage into orbit. The idea was for the astronauts to carefully approach the Agena and briefly dock with it. This proved to be much more difficult than it sounded. At first, the Agena failed to go into orbit. And even after docking successfully, the maneuver still involved a great deal of danger. After astronauts Neil Armstrong and David Scott rendezvoused and docked Gemini 8 with the Agena stage, the two spacecraft, which were now joined, began rolling wildly. Armstrong detached Gemini 8 from the Agena, but Gemini 8 continued to spin even faster. The hand controls failed, and even NASA’s mission control back on Earth didn’t know what to do. Finally, the controls started to function again and the astronauts were able to get their spacecraft under control. The final mission of Project Gemini was Gemini 12, launched on
One of the main goals of the Gemini program was to develop and practice the skill of rendezvousing two spacecraft while in orbit. At left, we see an astronaut’s view of a Gemini capsule carefully approaching a spacecraft. Unmanned Agena spacecraft were launched into orbit as practice targets for rendezvous maneuvers. But in one case (above right), the nose cone failed to separate, leaving the Agena looking like “an angry alligator,” according to the astronauts of Gemini 9. Unfortunately, the malfunctioning nose cone prevented the frustrated astronauts from safely rendezvousing with the Agena.
November 11, 1966, with astronauts James Lovell and Edwin “Buzz” Aldrin on board. Again, the spacecraft was preceded into orbit by an Agena. Aldrin practiced working in space using a variety of specially designed space tools while attached to the spacecraft by restraints. During the course of three space walks, he worked outside the capsule for a total of five and a half hours. Although the Gemini program had many problems, overall it was a great success. The astronauts practiced and perfected many of the techniques required for a mission to the Moon. The next step in the U.S. space program would be the Apollo lunar landings. Unlike Gemini, however, the Apollo program opened with a tragedy.
APOLLO TO THE MOON
Less than three months after the successful conclusion of the Gemini program, the first Apollo capsule was sitting atop its titanic Saturn 1B rocket. On January 27, 1967, NASA held a dress rehearsal for the launches that would eventually take place. Astronauts
Grissom, and Roger Chaffee were on board the Apollo capsule. They were testing the launch systems when a fire suddenly broke out. Although all the propellants had been removed from the capsule, the pure oxygen atmosphere caused the plastics inside to burn fiercely. Within fifteen seconds, the three men were dead from suffocation. It took ninety seconds for a rescue crew to open the hatch.
Top: The Apollo 11 spacecraft atop its giant Saturn V rocket. Middle: Astronaut Edwin “Buzz” Aldrin on the Moon. Bottom: Navy divers picked up the returning Apollo 11 astronauts at sea.
The Apollo launch schedule was put on hold for nearly two years. Engineers rethought and redesigned the capsule to make future capsules fireproof. It was not until October 11, 1968, that the first manned Apollo spacecraft, Apollo 7, went into orbit for an eleven-day mission. To everyone’s relief, the mission was a complete success. Astronauts Wally Schirra, Donn Eisele, and Walter Cunningham made 163 orbits of Earth. They demonstrated the ability of the spacecraft and its crew to make long-term space missions, which would be required for a lunar landing. The next U.S. mission was to the Moon—but not to land. Launched from Earth on December 21, 1968, Apollo 8 went into lunar orbit, circling the Moon ten times before firing its engines for its return to Earth. The crew spent Christmas 70 miles (113 km) above the lunar surface. They celebrated Christmas Eve by taking turns reading from the Bible’s book of Genesis. NASA sent Apollo 9 into orbit on March 3, 1969. It practiced rendezvous and docking maneuvers in Earth orbit. NASA launched Apollo 10 on May 18 of that same year. It was a full dress rehearsal for the lunar landing. Astronauts Thomas Stafford and Eugene Cernan piloted the lunar module (the spacecraft designed to land on the moon) to within 50,000 feet (15,240 m) of the lunar surface before returning to the command module (the main spacecraft). NASA declared that it was ready to make the first landing on the Moon.
THE FIRST FOOTPRINTS On July 16, 1969, one of the monster Saturn V rockets lofted three astronauts—Michael Collins, Buzz Aldrin, and Neil Armstrong—toward the Moon. After three orbits around Earth, the third and final stage of the Saturn rocket reignited. It accelerated the Apollo 11 spacecraft out
THE APOLLO COMMAND AND SERVICE MODULES The Apollo spacecraft consisted of two parts: the command module and the service module. The command module was a large, squat cone nearly 11 feet (3.2 m) tall and 13 feet (3.9 m) in diameter. With its three astronauts, it weighed 13,090 pounds (5,937 kg). At the top of the cone was a docking probe that allowed the command module to join with the lunar mod-
ule, which would ride to the Moon attached to the nose of the command module. A hatch allowed the astronauts to pass from one to the other. The service module contained the electrical power and life-support systems. It also held the propellant tanks and engine needed for boosting the spacecraft from Earth’s orbit to lunar orbit and back again.
The Apollo command module compared to the Mercury and Gemini spacecraft.
of Earth’s orbit and toward the Moon at a speed of more than 24,000 miles (38,624 km) per hour. Once the spacecraft was on its way, the third stage was discarded. The astronauts then began their first docking maneuver. The
(Above) Astronaut Neil Armstrong prepares to board the Apollo 11 spacecraft for his journey to the Moon. The thirty-nine-year-old was already an experienced test pilot and veteran of the Gemini 8 spaceflight.
lunar lander, called Eagle, had been stored in a “garage”
The enormous Saturn V rocket—the largest and most powerful rocket
below the command and serv-
ever built—takes off on July 16,
ice modules. The astronauts
1969, with the Apollo 11 astronauts
had to maneuver it around so
on their journey to the Moon.
that it was attached to the docking hatch at the top of the command module. Four days later, Apollo 11 was in orbit 69 miles (111 km) above the Moon. The astronauts had to begin the delicate operation of detaching Eagle from the command module and getting it ready for its descent to the lunar surface. Aldrin and Armstrong would make the landing while Collins remained in orbit in the command module.
THE SATURN V The three-stage Saturn V rocket was the largest, most powerful rocket ever built. When it was launched for the first time on November 5, 1967, it was as though a volcano had erupted in the middle of the Florida coast. In fact, its sound was compared to the volcano Krakatoa, whose 1883 explosion was the most powerful ever recorded. During launch, the roof of the nearby CBS television building collapsed. And the pressure waves generated by the five huge first-stage engines were detected more than 1,000 miles (1,609 km) away. Each of these engines produced 1.5 million pounds (1 million kg) of thrust. (Compare this to the 60,000 pounds (27,215 kg) of thrust created by the engine of
the V-2 and the 20 pounds (9 kg) of thrust created by Goddard’s first liquid-fuel rocket.) The Saturn V was the direct descendant of the V-2 rocket of World War II. It was developed from Wernher von Braun’s Redstone rocket. The Saturn V was enormous, standing 363 feet (111 m) high and weighing, at takeoff, 6,423,000 pounds (2,913,500 kg). Everything about the rocket was big. The five F-1 engines in the first stage produced about 7,650,000 pounds (3,470,000 kg) of thrust. It sucked about 3 tons (3 metric tons) of fuel and oxidizer every second from their massive tanks. This was forty times the power of the rocket that had launched Alan Shepard into space.
Collins pressed a switch, and the two spacecraft gently parted. “See you later,” he said to the departing astronauts. Eagle slowly pivoted until its engine faced forward in the direction the lander was traveling. When fired, the engine acted as a retrorocket, slowing down the spacecraft. Armstrong started the engine, and the lander began to lose speed. As it did, its orbit spiraled down toward the Moon. At an altitude of 7,200 feet (2,195 m), Eagle swung around until its engine pointed down. The lander kept falling until it was just 300 feet (91 m) above the surface of the Moon and traveling only 30 miles (48 km) per hour.
The first stage took the rocket to an altitude of 42 miles (68 km) in just two and a half minutes, reaching a speed of Mach 9. Then the second stage ignited, building on this speed to reach Mach 22— 15,000 miles (24,140 km) per hour—and an altitude of 117 miles (188 km). The third and final stage then took over, putting the Apollo spacecraft into Earth’s orbit.
The Saturn V rocket is huge compared to some of the rockets that preceded it, including the rockets that took part in the Mercury and Gemini projects. The Saturn V towered 363 feet (111 m) high—taller than the Statue of Liberty.
The planned landing site was a broad, smooth plain called the Sea of Tranquility (which is not actually a sea). It was chosen because it looked like a safe place: flat and not many craters. Scientists had gathered this information about the surface of the landing site from photos taken by Lunar Orbiter satellites. No one knew what the surface of the Sea of Tranquility looked like up close. It would not take a very big rock or crater to upset the lander. And very small rocks and craters were too small to be seen clearly in the Orbiter photos. Looking out the window, Armstrong saw that the landing computer was bringing them down onto a field of boulders. The lander
would tip over if it set down on any of them. He quickly switched off the computer and took over control manually. He skimmed over the boulders, with almost no fuel left for landing. But he still could not find a safe spot to land. Finally, miles beyond the designated landing area, Armstrong spotted a flat area. With only thirty seconds of fuel left, he began the final descent. Dust whipped past the windows as the blast from the engine hit the lunar surface. The astronauts could see nothing below them. Three of the landing pads had long antennalike feelers protruding from them. When they contacted the ground, a signal lit up in the cockpit: LUNAR CONTACT. A moment later, all four pads were touching the ground. “Houston,” reported Armstrong over the radio, “Tranquility Base here. The Eagle has landed.”
Apollo 11 astronaut Neil Armstrong took this photo (left) of his fellow moonwalker, Buzz Aldrin, as they explored the surface of the Moon. After a successful splashdown in the Pacific Ocean on July 24, 1969 (right), Apollo 11 astronauts were met by U.S. Navy divers who made sure that the capsule was floating safely. NASA chose to make water landings because these were deemed safer than landing a spacecraft on solid ground.
THE LUNAR MODULE The lunar module, which was used for the actual landing on the Moon, was a strange-looking vehicle that was compared to an insect or wind-up toy. One of the reasons for its odd shape is that it didn’t need to be sleek in order to reduce resistance to motion. It would operate only in the airless vacuum of space, where air resistance wasn’t an issue. The lunar module was nearly 23 feet (6.9 m) tall and weighed 33,205 pounds (15,061 kg). Measured diagonally from one landing pad to another, the lunar module was 31 feet (9 m) wide. At the top of the spacecraft was the docking hatch that allowed it to join with the command module. A small door in the side held the
ladder that the astronauts used to climb down to the surface of the Moon. The two astronauts rode standing up. They piloted the lander with much the same skills they would have used flying a helicopter. The astronauts rode in the ascent stage, which also contained the fuel and engine needed for leaving the Moon. Beneath the ascent stage was the large boxlike descent stage. The descent stage contained the fuel and engine necessary for landing on the Moon, as well as four landing legs with their padlike feet. When it came time to leave the Moon, the ascent stage used the descent stage as its launching pad.
Six more Apollo missions to the Moon followed, though only five made it that far. In November 1969, Apollo 12 landed astronauts Pete Conrad and Alan Bean on the Ocean of Storms (which is not actually an ocean), 1,000 miles (1,609 km) from Tranquility Base. One of the highlights of this mission was the astronauts’ visit to the Surveyor 3. This was an unmanned lunar probe, which had landed in April 1967. Conrad and Bean collected Surveyor’s camera and other parts so they could be returned to Earth for study. They also gathered 74 pounds (34 kg) of lunar rock samples.
APOLLO 13: MISSION THAT FAILED
Apollo 13 was headed for a landing in the Fra Mauro region of the Moon. On April 11, 1970, one of the oxygen tanks in the service module’s electrical power system exploded. Mission control in Houston, Texas, ordered the landing to be canceled. The three astronauts had to continue on to the
Moon but not land. They circled it before returning to Earth, because a spaceship cannot simply be turned around like a car or airplane. The astronauts had to depend on the oxygen reserves carried in the lunar module, which they used as a kind of “lifeboat” until once again arriving in Earth’s orbit.
For safety’s sake, the first two lunar missions had landed on relatively smooth areas called maria (Latin for “seas”), which are flat, waterless lava plains. Apollo 14 was launched on January 31, 1971. It was to explore the highlands of Fra Mauro, a mission it had inherited from Apollo 13. The area was on the edge of Mare Imbrium, a vast plain of lava created millions of years ago when a huge asteroid punched through the lunar crust. An electrical flaw canceled this plan. The terrain of Fra Mauro was very different from the nearly featureless regions Apollo 11 and Apollo 12 had explored. The moonwalkers, Alan Shepard and Ed Mitchell, discovered that they were having a hard time finding their way around on the surface. Much of the problem was due to Shepard’s lack of interest in learning about the area before he left Earth. Although he didn’t gather much scientific data or samples, Shepard did pull a memorable stunt. He had brought along a golf ball, and using a specially made golf club, he sent the ball sailing “Miles and miles and miles!” he said. (The golf club is on display at the Smithsonian National Air and Space Museum in Washington, D.C.) The following mission, Apollo 15, was launched on April 16,
1972, and it was much more successful. It explored one of the mysterious lunar rilles (riverlike channels that crisscross the lunar surface). Scientists knew the rilles hadn’t been created by flowing water. They were the wrong shape for that. So the scientists wanted to figure out what had caused them. NASA chose Hadley Rille as the best site to explore. It is at the edge of the towering, 14,000-foot (4,267 m) Hadley Mountains. The area also has a large number of interesting craters that might have volcanic origins. Scientists hoped the mission would return with a rich harvest that would help make up for the disappointment of Apollo 14. Apollo 15 astronauts David Scott and Jim Irwin brought along a sophisticated piece of equipment: a Lunar Roving Vehicle (LRV). The LRV was an electrically powered car that resembled a dune buggy. It allowed the astronauts to travel much farther and carry more equipment than any previous lunar explorers. Apollo astronaut Alan Shepard stands next to the Modularized Equipment Transporter, which was used to carry various scientific experiments and equipment.
Apollo 15 astronauts had the luxury of their own wheels while exploring the Moon. Although it looks a lot like a beach buggy, the Lunar Rover was a highly sophisticated machine designed to work in the extreme temperatures and airlessness of the Moon. It allowed astronauts to explore many more miles of the lunar surface than they could have on foot.
Built mostly of lightweight aluminum, the LRV was powered by electric motors and batteries. Its tires were basketlike wheels woven from coated piano wire. It had a maximum speed of 8.7 miles (14 km) per hour. The 1,600-pound (726 kg) LRV was equipped with radio antennas, television and still cameras, storage compartments for samples, and controls for the astronauts. Astronauts Scott and Irwin spent three days on the Moon. For twenty-two hours and thirty-six minutes, they were outside the spacecraft exploring Hadley Rille and the area around it. One of their most important discoveries was a small white rock found on the slopes of Mount Hadley. It was a fragment of the earliest lunar crust—at least 4.5 billion years old. “I think we just found what we came for,” Scott declared. It was a piece left over from the formation of the Moon. Unfortunately, the astronauts spent a lot of time getting core samples. As a result, they had to abandon plans to explore the mysterious
craters that some scientists thought might be ancient volcanoes. But scientists were still anxious to discover whether any of this volcanism might be recent. Was the Moon still geologically active? No one knew. Apollo 16 would have to try to find the answer to this question.
The Apollo 15 lunar module sits in front of the slopes of the lunar Apennine Mountains. The Moon’s surface—mostly a fine rock powder—shows the tracks made by the astronauts’ Lunar Rover.
THE LAST FOOTPRINTS Astronauts John Young and Charlie Duke landed in hills near the crater Descartes on April 21, 1972. The region was filled with what looked like lava flows and ash falls. If there was any place that might reveal the secrets of lunar volcanic activity, this would surely be it. Unfortunately, the scientists were disappointed. Technical problems prevented some crucial experiments from being performed, while the Moon itself disappointed them. The signs of volcanic activity they’d hoped to find were nowhere in sight. In 1972 Apollo 17 took the final trip to the Moon. The Apollo program was supposed to include twenty missions, but the U.S. Congress decided to cut the series short. After all, much of the reason for going to the Moon in the first place was political: to get there before the Soviets did. Once this goal had been accomplished, the politicians who were controlling NASA’s budget thought that the United States had made its point. (Other landing sites would have included the crater Alphonsus. This location was known for strange phenomena—called transient lunar phenomena—such as glowing areas and cloudy patches. Another goal had been landing on the far side of the Moon, the side forever hidden from Earth.) Although the cancellation of the program was disappointing, NASA had no reason to be disappointed in the results of the Apollo 17 mission. The moonwalkers were astronaut Gene Cernan and geologist Dr. Harrison Schmitt—the first trained scientist to visit the Moon. They landed in Taurus-Littrow Valley, a rugged region that lies between two vast mountains. Cernan and Schmitt spent a total of twenty-one hours and five minutes exploring the landscape. They traveled nearly 22 miles (35 km) in their Lunar Rover and accomplished a rigorous program of experiments. They set off explosive charges and measured the echoes
received from deep beneath the surface. Since shock waves travel differently through different materials, the explosions allowed scientists to learn more about the Moon’s crust. During the mission, the astronauts discovered a patch of distinctly orange soil. This was a startling color to discover on the universally dark gray lunar surface. In fact, they had finally discovered signs of volcanic activity on the Moon! Cernan and Schmitt also spent a great deal of time examining an enormous block of stone that had rolled down the mountainside. They named it Split Rock. When they left the lunar surface, it marked the end of the last human visit to the Moon. In the decades since then, no one has been back. In fact, the Soviet Union never achieved the goal at all. The triumph of the Americans, combined with technical problems in developing a lunar spacecraft, convinced the Soviets to abandon their plans to send cosmonauts to the Moon.
Apollo astronauts left the first human footprints on another world. Thirty years later, they are still the only footprints on the Moon.
Apollo astronauts brought back enough data about the Moon to keep scientists busy for decades. In fact, scientists are still studying these materials and learning new things about Earth’s nearest neighbor. More than sixty research laboratories around the planet are devoted to studying Apollo data and samples. Perhaps the most important question answered by the Apollo missions was “Where did the Moon come from?” In the past, there had been many theories, but none seemed to account for all the facts.
APOLLO-SOYUZ The last flight of an Apollo spacecraft was made in July 1975 as part of a joint U.S.–Soviet project called the Apollo-Soyuz Test Project (ASTP). This project marked the first time that the United States and the Soviet Union cooperated in a space mission. The Soyuz spacecraft (below left) contained two cosmonauts. Valery Kubasov had already flown one previous mission into space.
Mission commander Alexei Leonov had made the world’s first space walk a few years earlier. Three U.S. astronauts—Thomas Stafford, Deke Slayton, and Vance Brand—flew their Apollo capsule into orbit. Along with the command/service module was a docking module that allowed the U.S. and Soviet spacecraft to join up. The two spacecraft (below right) were launched seven and a half
Scientists now know that the Moon is almost as old as Earth: nearly 4.6 billion years old. The Moon is also made of materials similar to those that make up Earth and in similar proportions, though it has much less iron than Earth. These similarities in age and material have led scientists to believe that Earth and the Moon share a common history. The current theory is that an object nearly the size of Mars struck the early, molten Earth. Debris from the collision blasted into orbit around Earth. Eventually, this material came together to form the Moon as we know it.
hours apart. After docking, the hatch between them was opened and the astronauts and cosmonauts exchanged the first international handshakes in space. The five men spent time in one anothers’ spacecraft (above), where they shared meals and jointly performed scientific experiments. They also practiced rendezvous and docking. (One of the goals of ASTP was to develop techniques for the rescue of stranded astronauts.)
The spacecraft remained linked for a total of forty-four hours. After separating for the next-tolast time, the Apollo capsule was used to create an artificial eclipse of the Sun for the benefit of the Soyuz cosmonauts. Blocking the Sun allowed the cosmonauts to study the solar corona, which can’t normally be seen in the glare of full sunlight. Finally, the ships separated for the last time.
– 6 Astronauts made great strides by spending a few days in orbit and exploring the surface of the Moon. But they couldn’t easily conduct scientific research and experiments in such a short time and in the cramped setting of a space capsule. Scientists wanted astronauts to be able to stay in orbit for weeks or even months at a time, having plenty of room for equipment and moving around. This would require an entirely new type of spacecraft, one that was meant to remain in orbit permanently. This type of spacecraft is called a space station. It would orbit Earth all the time, with spaceships shuttling crews and supplies back and forth from Earth.
The idea of the permanently orbiting space station had been around almost as long as the idea of space travel. In fact, both Tsiolkovsky and
Top: The U.S. Skylab
Oberth had proposed designs. One of the earli-
space station. Middle:
est studies was published in 1928 by an
The Soviet Mir space station with a U.S.
Austrian soldier named Hermann Potoˇcnik, writ-
space shuttle docked to
ing under the name of Hermann Noordung.
it. Bottom: The
Potoˇcnik’s writings were so detailed that he
even included an orbiting space telescope.
In 1929 Hermann Potocˇ nik designed the most detailed and elaborate space station up until that time. In this illustration, the space station is in the center with its dishshaped solar power generators. The living and working area is the red doughnut shape in the middle of the large dish. It rotated to provide a sense of gravity for the people on board. Above and to the right of the station is an auxiliary power generator, and to the left is a space telescope.
Oberth, Potoˇcnik, and others realized the scientific value of the space station. But others saw its greatest value as being a steppingstone or way station for spacecraft traveling from Earth to the Moon and other planets. Many of these early space station designers suggested that the station be made in the form of a huge, rotating doughnut. The rotation could provide artificial gravity for the astronauts working inside. (Many early space pioneers thought that prolonged exposure to weightlessness would be dangerous, so they proposed using some form of artificial gravity. After humans actually started traveling in space, scientists discovered that medical problems associated with long periods of weightlessness only occur after many weeks of spaceflight.) The most famous space stations designed before the era of spaceflight looked like rotating doughnuts. Wernher von Braun created the design for his Collier’s magazine series in the early 1950s.
THE BRICK MOON The first mention of an artificial Earth satellite was made in the short novel, The Brick Moon, by American author Edward Everett Hale. Published in 1869, the story describes plans to launch a 200foot (61 m) brick sphere into Earth‘s orbit, which would act as an aid to navigation. Unfortunately, the sphere is launched
prematurely with most of the workers and their families on board. Although written in a humorous tone, Hale nevertheless succeeded in anticipating many of the functions of modern space stations. He described weather observation, orbital rendezvous, biological experimentation, mapmaking, and many other tasks.
His station was an enormous wheel 250 feet (76 m) in diameter that held several hundred people. It would rotate about three times a minute to create artificial gravity for the personnel.
Wernher von Braun designed this space station (right) in the early 1950s. Like many other engineers of that time, von Braun thought that long-term space travelers would need artificial gravity. Von Braun had his station rotate, so that the astronauts living and working in the hollow ring would feel a sense of gravity. Von Braun also designed space shuttles (left) that would carry personnel and supplies to and from the station and even space telescopes and space taxis.
A full-scale replica of a Salyut space station (with its Soyuz spacecraft attached on the right) is on display at a science museum in Russia (once a part of the Soviet Union).
SALYUT The Soviets placed their first space station, Salyut 1, in orbit in April 1971. (Salyut means “salute” in Russian.) Its main body was a cylinder about 43 feet (13 m) long and 14 feet (4.2 m) in diameter. It had two other components: a docking/air lock compartment and an instrumentation/propulsion module. The entire station weighed 21 tons (19 metric tons) and could accommodate as many as five cosmonauts. (Most scientists don’t consider Salyut to be a true space station because of its small size and temporary nature.) The crew performed astronomical observation in stellar spectroscopy, which can determine what elements make up different stars. They examined gamma rays (which are emitted by supernovas and other cosmic events) and observed Earth’s resources (such as farms and forests). The crew also performed experiments on growing plants in weightlessness.
An important series of studies was devoted to observing the cosmonauts themselves
reactions to prolonged weightlessness. This data would prove vital if flights to Mars are ever made, which would take many months. The Soviets quickly discovered that cosmonauts subjected to long periods of weightlessness lose bone Soviet cosmonauts work in the
mass and muscle tone for many
Salyut 7 space station, which was
of the same reasons a bedrid-
launched into space in 1982. Several different crews ran the
den hospital patient does.
station until it was allowed to fall
Salyut 1 reentered Earth’s at-
from orbit in 1991.
mosphere in October 1971. Six more Salyut stations
were placed in orbit after Salyut 1. An explosion on board Salyut 2 destroyed the station before its crew arrived. The remaining missions combined military and scientific goals. Salyut 7 cosmonaut Svetlana Savitskaya was the first woman to fly in space twice and the first to perform a space walk. The final Salyut station was launched in 1982.
SKYLAB The first real space station was Skylab. (The earlier Soviet Salyut space stations consisted only of two Soyuz spacecraft docked together.) NASA created Skylab to take advantage of leftover components of the recently canceled Apollo program. The station was
SKYLAB SPECS Skylab consisted of four distinct parts. The main laboratory and living area—the orbital workshop—was a cylinder 48 feet (14 m) long and 21 feet (6 m) in diameter. Attached to one end was the instrument unit, the air lock module, and the multiple docking adapter. The multiple docking adapter allowed an Apollo command module to dock with the station and load and unload crew members. The Apollo Telescope Mount (ATM)—
adapted from the body of a lunar lander—was attached to one side of this cluster. The workshop had four large square solar panels attached to it like big wings. These provided electric power for the station. The ATM had its own solar panels: four long, narrow ones that made the station look something like a windmill. The entire station weighed 186,731 pounds (84,700 kg)—as much as Christopher Columbus’s flagship, the Santa Maria.
actually an empty Saturn V third stage that was 85 feet (26 m) long and 22 feet (6.7 m) wide. NASA converted it into a spacious, two-story laboratory for a three-person crew. The lower section included a wardroom, sleeping quarters, and a washroom/toilet designed for use in weightlessness. The upper section was for storage, for conducting experiments, and for housing exercise equipment, including a stationary bicycle and treadmill. The entire station was launched into orbit carrying water, oxygen, food, and other supplies for the nine astronauts who would be working in the station over the course of three separate missions. Skylab took off in May 1972. This unmanned launch is officially called Skylab 1. Within a few moments, Skylab suffered severe damage. The spacecraft traveled at thousands of miles an hour as it sped toward orbit. Air rushing past it had torn away Skylab’s micrometeoroid shield. This thin layer of metal was intended to protect the laboratory from tiny meteors, as well as the scorching heat
of the Sun. Worse, metal from the disintegrating shield had caused one of the big solar panels to tear off. The other panel was damaged and would not open. As a result, the station had no power. With the loss of the heat shield, the temperature inside the station began to climb. If nothing was done about it, the station would become uninhabitable. Even if the temperature wasn’t high enough to hurt the astronauts, the heat would damage delicate instruments and ruin food and medical supplies. It was also possible that high temperatures might cause the plastics on board to give off toxic fumes. Could Skylab be repaired? Astronauts Charles Conrad, Joseph Kerwin, and Paul Weitz discussed the problem with engineers. The solution was almost too simple: shade Skylab with a big umbrella. If something like that could be devised quickly enough, it might work to save the station. But what about the broken solar panel? That, they decided, would have to wait until the astronauts got there. When astronauts arrived eleven days later (officially called Skylab 2), they confirmed the damage that mission control had suspected. But they also discovered that it was only the beginning of their problems. They attempted to pull the stuck panel free with a long hooked pole, but they failed. Then, when the astronauts tried to dock their command module with the station, the docking latches failed to lock. After eight attempts, they finally gave up, climbed into their space suits, and tried to make the repairs by hand. They were successful, and the next attempt to dock worked. The exhausted men spent the night sleeping in their spacecraft. The next morning, they entered the station carefully, using a poison detector in case the plastic had released toxic fumes. All was well. They could breathe safely. The astronauts brought the umbrella on board and extended it through one of the workshop’s ports. The thin Mylar sheet expanded on
flexible rods like an enormous golden kite, shielding the body of the station from the Sun’s heat. Temperatures on board immediately began to drop. The
wasn’t done yet. Before the astronauts could begin any scientific experiments, the broken solar panel needed to be fixed. The equipment needed more power than one wing could provide. Everything they’d done up to that point seemed easy com-
The Skylab space station was
pared to the task ahead.
successful in spite of being badly
The solar panel was being held in place by a thin alu-
damaged during takeoff. Only one of the two solar panels succeeded in opening, limiting the amount of
minum strap entangled deeply
electrical power. A makeshift
within the remnants of the lost
umbrella had to be created and
wing. To free the folded panel,
fitted in place by spacewalking
the astronauts had to cut the al-
astronauts to keep the station cool. The umbrella is the gold-colored
most inaccessible strap. The
“blanket” that covers the nearest
only way to reach the strap was
portion of the station.
for Kerwin to attach a pair of pruning shears—like those used to trim tree limbs—to a long aluminum pole. But with little to hold on to, he had no way to brace himself. Over and over again, he found himself dangerously snarled in the lines that attached him to the station. At one point, Kerwin’s heart rate raced from a normal 70 beats a minute to a terrifying 150. Mission control ordered him to take a
break. Ten minutes later, he managed to anchor himself and get the shears in place. He cut the strap. At the same time, Conrad pulled on a line attached to the wing. It suddenly came free and unfolded, launching the two astronauts into space. They would have been lost if it hadn’t been for the tethers attaching them to the station. Almost immediately power started to increase. Skylab was in business at last. For eighty-two hours, the astronauts observed the Sun and photographed more than 4 million square miles (10 million square km) of Earth’s surface. They also conducted many biomedical experiments—more even than they had planned. This work provided vital information about the effects of working in space for long periods of time. The data were important for the future of spaceflight.
AN ORBITING LABORATORY Skylab 2’s crew returned to Earth after a mission lasting twenty-eight days. The next mission (Skylab 3)—with Alan Bean, Owen Garriot, and Jack Lousma—was highly successful, although it had a few nerveracking moments early on. After the crew members arrived at the space station, they discovered that the Apollo command module they had used to travel from Earth was leaking fuel. This problem might have prevented a safe return to Earth, so NASA immediately put a rescue mission into the works. It was the first time in the history of any space program this had to be done. The plan was to fly a spare Apollo module into orbit to pick up the stranded astronauts. Fortunately, the leak turned out to be less serious than NASA thought, and the rescue mission was unnecessary. After fifty-nine days, that crew was replaced by the last trio of astronauts—Gerald Carr, Edward Gibson, and William Pogue. They were launched on November 16, 1973. They watched Comet Kohoutek
Skylab 4 astronauts used instruments that focused only on certain wavelengths of light. They captured this image of the Sun with a huge eruption taking place on the left.
as it rounded the Sun, observed solar flares, and took forty thousand photos of Earth. These photos provided valuable information about agriculture, geology, forestry, meteorology, geography, and oceanography. The crew also performed more medical experiments than the previous missions, including an increased use of exercise equipment especially designed for use in weightlessness. When the astronauts returned to Earth after their record-breaking eighty-four days in space, they were in better physical condition than the previous Skylab crews. In fact, they’d grown taller by 1 inch (2.5 cm) or more! Without gravity to compress the vertebrae in their backs, their spines had actually expanded. They soon returned to their normal heights when they were back on Earth. The Sun ultimately decided the fate of Skylab. Although NASA had planned to keep the space station operational until the 1980s, increased sunspot activity had warmed Earth’s upper atmosphere, causing it to expand. It had extended to within Skylab’s low orbit. The
drag—as slight as it was—started to slow the station. It began to fall back to Earth, and no one could do anything about it. Scientists were worried about the large size of Skylab. A small spacecraft, such as a satellite or Apollo capsule, would simply burn up from atmospheric friction long before reaching the ground. But Skylab weighed 100 tons (91 metric tons). NASA feared that when it disintegrated, pieces might fall to the ground. Even though more than 70 percent of Skylab’s path was over water, there was still a possibility that it might reenter over land. In fact, on Skylab’s final day, scientists learned that it would come down over North America. Fearing what might happen if a piece of equipment weighing several hundred pounds landed on a city or town, NASA fired the station’s thrusters, extending its orbit by half an hour. This repositioned it to fall into the South Atlantic or southern Indian Ocean. After 34,981 orbits, Skylab fell to Earth on July 11, 1979. Most of its fragments fell into the Indian Ocean, as expected. But pieces were eventually found as far away as Australia, where a fragment weighing more than 1,000 pounds (500 kg) landed on a farm. Ultimately, NASA was lucky that day. No one had been harmed by the disintegration of the space station.
MIR The Soviets launched the space station Mir (meaning “Peace”) in February 1986. Mir was the next stage in the modular Soviet space station program. By assembling their stations from separate modules—like building a model from Lego bricks—a space station could grow to any size. It could even become a virtual city in space. The central core of Mir was a second-generation Salyut, about 43 feet (13 m) long and almost 14 feet (4.1 m) in diameter. At one end was a spherical transfer compartment with five docking ports. The transfer
The Mir space station, photographed by a space shuttle astronaut, had flat panels that generate electricity from sunlight. The large white cylinders were laboratories and living modules. On the most distant module, near the top of the picture, was a Soyuz spacecraft used for transporting personnel to and from the station. The small object directly opposite the Soyuz was an unmanned Progress spacecraft that delivered food and supplies to the station.
compartment allowed a spacecraft to dock at one end of the station and as many as four additional modules to attach at right angles to the main body. Several large solar panels provided power. Over time, Mir acquired seven modules, along with a large number of solar panels. Mir was the world’s first continuously inhabited space station. A specially designed Soyuz-style spacecraft was developed for the transfer of crews to and from Mir. The Soviets also developed an unmanned supply ship called Progress. Cosmonauts and astronauts from many different countries performed missions on board Mir. In 1993, after the U.S. space station Freedom was converted to an international project, NASA entered into an agreement with the
Space shuttles visited the Mir space station often, transferring astronauts on special missions.
Russians. (The Soviet Union had dissolved in 1991. Russia is the largest of the former union’s republics.) NASA would contribute to the work on Mir as part of the preparations for building a larger station. Space shuttles would help transport personnel, food, and supplies. U.S. astronauts would spend months on board conducting research. Eventually, seven astronauts spent a total of twenty-eight months on Mir. This experience was not always pleasant for either the Russians or the Americans. Aside from language and cultural differences, it was hard for either side to forget that their countries had only recently been bitter rivals during the space race. After fifteen years in orbit, the aging Mir space station fell into Earth’s atmosphere on March 23, 2001, and was destroyed. At the time of Mir’s conception, the Soviets had planned to follow up with Mir 2. The core module of this space station had been built but became a part of the International Space Station (ISS).
INTERNATIONAL SPACE STATION In 1984 U.S. president Ronald Reagan approved the design and construction of a large permanent station in space. In some ways, it was to be the United States’ answer to the Mir space station. It would have provided an observation post for astronomers and Earth scientists, a facility for satellite repair, a laboratory for microgravity research, and more. However, the original ambitious concept was soon deemed to be too expensive. NASA scaled it down drastically. It went through seven major design changes, each of which reduced the station’s capabilities. In 1993 it officially evolved from the wholly U.S.-owned space station Freedom to the International Space Station, a project involving many different nations. The ISS has become the largest and most complex international science project in history. Contributing to its construction and operation are the scientific and technological resources of Canada, Japan, Russia, Brazil, and the eleven nations of the European Space Agency. The ISS is more than four times as large as the Mir space station. When completed, the ISS will measure 356 feet (108 m) across and 290 feet (88 m) long, with almost 1 acre (0.4 hectare) of solar panels The International Space Station was photographed by space shuttle Discovery astronauts on July 26, 2005. A Russian Soyuz spacecraft is attached to the station in the lower part of the picture.
providing electrical power to six scientific laboratories. The space station is in orbit around Earth at an altitude of approximately 220 miles (354 km). Its orbit allows scientists to pass over 95 percent of Earth’s human population and observe 85 percent of Earth’s surface. When completed, the ISS will be a collection of pressurized units connected to a central truss. (This truss will also support four large groups of solar cells that will provide all the electrical power for the station.) The ISS will have ten main pressurized units and a number of smaller pressurized sections. These include air locks, crew and supply transport vehicles, and “lifeboats” in case of emergency. Several unpressurized units will contain service and maintenance equipment and scientific experiments. Space station crews will conduct science experiments on a daily basis and in a wide variety of fields—especially the life sciences, physical sciences, and Earth observation. In 2005, for instance, ISS astronauts took key photos of Hurricane Katrina damage in Louisiana and Mississippi, as well as damage and recovery efforts following the 2004 tsunami in Southeast Asia. They also documented the effects of
An artist’s depiction shows how the International Space Station will look when it is completed. It will be an imposing structure.
floods and droughts around the world. Scientists will do a great deal of research on the possibility of making products in space. There are advantages to working in a weightless environment. For instance, many molten materials mix together very differently in space than they do on the surface of Earth. This could result in new, improved alloys (combined metals) for use in electronics and manufacturing. The growth of crystals, especially, is very much affected by gravity. In a normal gravity environment, protein crystals grow imperfections and impurities. Aboard the ISS, nearly perfect protein crystals can be grown. This will allow the development of more pure pharmaceutical drugs, foods, and other crystalline-based products, including insulin for diabetes patients. The ISS mission is also concerned with education. Between 2000 and 2006, twenty-four educational workshops were undertaken that involved more than 31 million students and 12,500 teachers. In the student EarthKAM experiment, nearly one thousand schools and 66,000 middle-school students have controlled a digital camera on board the ISS to photograph features on Earth. These students have been able to study deforestation, volcanoes, river deltas, pollution, and many other subjects. Some of the most important research continues to be on the effects of long-term spaceflight on the human body. This information will be vital when it’s time for the first human expeditions to Mars and beyond. Even a few weeks in a weightless environment can have serious effects on the body. A trip to Mars and back may require a year or perhaps even two years of weightless flight. Researchers believe that such long-term spaceflight may pose other problems—both physiological and psychological—but they will not know for sure until they conduct more research on the ISS.
THE SPACE SHUTTLE
The space shuttle (officially known as the Space Transportation System, or STS) is the direct descendant of the rocket-propelled aircraft that began with the flight of Fritz von Opel’s rocket glider in 1928. Rockets specially constructed to ferry personnel and materials to and from orbit were part of Oberth and Potoˇcnik’s space station plans in the 1920s. Space shuttles also played a vital role in the space program that von Braun envisioned in the early 1950s. The shuttle was also a prod-
Top: This photo, taken during the launch of a space shuttle, illustrates a
uct of lifting-body research. Lifting
major difference between two types of
bodies are aircraft that depend on
rocket motors. The two solid-fuel
the shape of the fuselage (the cen-
boosters attached to the sides of the
tral body) for lift (getting up in the
large orange main tank produce an intense flame and thick clouds of
air) instead of the wings. Lifting
smoke. The three main engines,
bodies are strange-looking crafts
however, produce only a bright glow
that resemble flying steam irons.
and no visible flame. Bottom: Many
But their shape and flying qualities
different plans have been put forth to replace the aging fleet of space
make them ideal models for space-
shuttles. The design shown here doesn’t
craft that need to glide to a landing
depend on boosters of any kind. The
on Earth. For instance, their flat
shuttle would take off like conventional
bottoms make perfect heat shields and their lack of wings reduces air friction.
aircraft and use advanced jet engines to accelerate to great speeds and extreme altitudes.
These are just three examples from among the many dozens of space shuttle designs NASA researched during the 1970s. Every possible combination of booster and spacecraft was considered, including piloted booster rockets that could be flown back to the launch site and reused. Ultimately, the decision was based on budget and the least expensive design was chosen.
THE SPACE SHUTTLE U.S. president Richard Nixon established a Space Shuttle Task Group in 1969. Its first job was to decide what would be the best configuration for the shuttle. The task group eventually decided that it should consist of two rocket-powered aircraft. This design was much like the shuttle that Walter Dornberger and Krafft Ehricke proposed twenty years earlier. One of the rockets would be a booster, and the other an orbiter. The two would take off together. At a certain altitude, they would separate. The booster would be flown back to its base while the orbiter would continue on to orbit. It was to be a fully reusable concept. There would be no expensive throwaway stages, such as the Saturn V had.
But budget considerations began eating away at the design. While it might have been cheaper in the long run to have a reusable booster, initial development costs limited the project to the orbiter alone. It would have to be launched using expendable components. More money could be saved, the task group decided, if the orbiter didn’t have to carry its own fuel. The fuel could be contained in a throwaway external tank. This way, the shuttle could be made smaller and less expensive. Strap-on solid-fuel booster rockets would have to be added, however, since the shuttle’s main engines would not be able to provide enough thrust on their own to get the spacecraft into orbit. By 1972 the shuttle had more or less reached its final configuration. It became a lifting-body orbiter with an external fuel tank and two solidfuel boosters. The relatively small orbiter is dwarfed by these components. While the spaceplane is only 122 feet (37 m) long, the external tank is 154 feet (47 m) tall and the two boosters are each 149 feet (45 m) tall. The first orbiter, named Enterprise at the insistence of legions of Star Trek fans, was first tested in 1977. It went through unpowered glide and landing tests, with the shuttle launched from the back of a specially adapted Boeing 747. As big and clumsy-looking as the shuttle may appear, its performance surprised its test pilots, who compared its handling characteristics to a fighter jet. (The Enterprise has become part of the permanent collection of the National Air & Space Museum in Washington, D.C.)
THE SPACE DELIVERY VAN On April 12, 1981, the space shuttle Columbia rose from its launchpad at Kennedy Space Center in Florida, carrying commander John Young and pilot Robert Crippen. After a relatively uneventful mission, Columbia landed at Edwards Air Force Base in California just fifty-four hours and twenty minutes after takeoff.
THE SPACE SHUTTLE UP CLOSE The space shuttle is a triangularwinged aircraft with a single vertical tail fin. It has ordinary control surfaces for flying within the atmosphere and thrusters for maneuvering in airless space. The cabin has three levels: the flight deck, the middeck, and a utility area. The commander and pilot sit on the flight deck, with two mission specialists sitting behind them. The middeck has three more seats, as well as a galley, toilets, sleeping facilities, lockers, a hatch, and an air lock.
Behind the cabin is a large payload bay that takes up most of the fuselage. It is 60 feet (18 m) by 15 feet (4.5 m)—large enough to carry a city bus. Inside the bay is the Remote Manipulating System— a remote-controlled mechanical arm called the Canadarm (because it is manufactured by a Canadian company). It allows the astronauts on board the shuttle to move objects in the bay without having to leave the cabin.
The space shuttle has three main systems: the solid-fuel boosters, the external tank, and the space shuttle itself. The two solid-fuel boosters help speed up the spacecraft. Once they’ve burnt out, they are discarded. The huge central external tank contains the liquid hydrogen fuel and liquid oxygen oxidizer that feed the shuttle’s three main engines. (The shuttle itself doesn’t carry fuel on board.) Once the external tank is empty, it too is discarded and the shuttle continues to coast into orbit.
NASA’s fleet of five shuttles has made more than one hundred flights, covering a distance of over 430 million miles (692 million km) in more than sixteen thousand orbits. Their crews have spent a total of nearly three years in orbit. During that time, the shuttles and their astronauts have launched satellites and space probes and have repaired or returned satellites to Earth. They’ve ferried crews to and from the ISS and have conducted important scientific research. Among the most historic and important shuttle missions have been the launches of several planetary explorers. In 1989 shuttle crews sent the Magellan spacecraft on its way to Venus. Once in orbit around Venus, Magellan sent back to Earth more information about that planet than scientists had ever had before. Later that same year, the space shuttle carried the Galileo space probe into orbit. From there Galileo was launched on its mission to Jupiter. While in orbit around Jupiter, Galileo gathered brandnew details about the giant planet and its largest moon. In 1990 the space shuttle carried the Hubble Space Telescope into orbit. Later shuttle crews have been responsible for maintaining and servicing the telescope. The Hubble can observe stars and galaxies in a detail impossible to achieve with ground-based telescopes, which have to gaze through Earth’s thick atmosphere. Discoveries made by Hubble have transformed our knowledge of the universe. The shuttle has the most reliable launch record of any rocket in operation. Since 1981 it has boosted more than 3 million pounds (1.3 million kg) of cargo into orbit. More than six hundred crew members have flown on its missions. Although NASA has used it for more than twenty years, the shuttle has continually evolved. The modern shuttle is safer, more reliable, and more capable than ever before.
So far, humans have walked on the surface of only one body in the solar system other than Earth. Altogether, twelve Apollo astronauts have visited the Moon. Since that final Apollo mission, human exploration of space has been limited to only a few hundred miles from Earth. Meanwhile, scientists have been relying on robot explorers to visit other worlds. Some of these probes have only flown past their targets, taking measurements and photos as they zoomed by at thousands of miles an hour. Other probes have gone into orbit, allowing months or even years of study to take place. A few others have actually landed on other worlds. From these probes, we have learned that Mercury is a barren, heavily cratered world that
resembles our own Moon. We have learned that Venus is a hostile world with crushing surface pressures, heat that would melt lead, and sulfuric acid rain. We have learned that Mars is a beautiful planet that closely resembles our own—though it’s often bitterly cold and has little breathable air. We have also learned that Jupiter and its moons are a miniature solar system. One of those moons—Europa—may harbor life in a vast ocean hidden beneath its icy crust. The probe New Horizons was launched in January 2006. It will fly past Pluto and one of its moons in 2015. It will continue on to the outer reaches of the solar system until 2020. New Horizons may allow scientists to discover just how our solar system and home planet were formed.
Nevertheless, the space shuttle is limited in how much payload it can take into orbit. The shuttle cannot lift extremely heavy payloads, as the Saturn V or Delta rockets can. The shuttle cannot go to very high orbits above Earth—typically only about 200 miles (322 km)—nor can it travel to the Moon or Mars. NASA is exploring new concepts for launch vehicles that are more versatile than the modern space shuttle.
8 More than thirty years after the last human being walked on the Moon, NASA plans to return to that world. In 2004 U.S. president George W. Bush announced that NASA would eventually retire its aging space shuttle fleet. It will develop a new type of vehicle and consider returning astronauts to the Moon. A replacement for the space shuttle fleet is the first item on NASA’s agenda. Rather than using the same spacecraft to both carry heavy payloads and passengers to orbit, the job will be
Top: The next generation of lunar
split between two different types of spacecraft.
lander. Bottom: The
NASA will use an unmanned heavy-lift launch ve-
next century may see
hicle exclusively for heavy payloads and a smaller
the terraforming of
shuttle for ferrying passengers to and from space. In 2006 President George W. Bush announced that the United States would finally return to the Moon. In addition to exploring the Moon, the plan includes the creation of a permanent base in which scientists can stay for long periods of time. The lunar exploration program—part of a combined Lunar–Mars exploration program called Constellation—will require entirely new spacecraft.
worlds such as Mars, making them habitable by human settlers.
The first of the new launch vehicles to replace the space shuttle will be the Ares I. It will transport the Orion crew exploration vehicle and its crew and cargo to a low orbit of Earth. The Orion, in turn, will be the modern equivalent of the Apollo command module. The Ares I will be able to heft 55,000 pounds (24,950 kg) of cargo or personnel into Earth’s orbit. (By contrast, the space shuttle can carry only 53,700 pounds [24,357 kg] to low Earth orbit.) The larger Ares V, which will be used to launch human expeditions to Mars, will be able to carry 286,000 pounds (129,700 kg) to low Earth orbit. This giant rocket will stand 360 feet (110 m) high—three-quarters the height of the Washington Monument.
These artistic renderings show the two different Ares boosters that are part of NASA’s plans to return to the Moon. Ares I, on the left, uses a single five-segment solid-rocket booster—derived from the space shuttle’s solid-rocket booster—for the first stage. The second stage is a liquidfuel rocket. On the right is the Ares V. Its first stage has liquid-fuel engines mounted below a larger version of the space shuttle’s external tank. It also has two solid-fuel rocket boosters. The second stage is similar to that of the Ares I. This versatile system of boosters will carry cargo and components for flights to the Moon and later to Mars.
NASA’s plans to return to the Moon include a new and improved lunar lander, shown in this artistic rendering. Much larger than the lunar module of the 1960s, it will be able to carry more astronauts, supplies, and equipment to the lunar surface, enabling longer stays and more extensive exploration.
NASA plans to launch two Ares V rockets. The first will be a cargo vehicle carrying the Earth departure stage and the lunar landing module. The second will carry an Orion crew vehicle holding four astronauts. The Orion will dock with the lunar module while in Earth’s orbit. The Earth departure stage will then propel both on their journey to the Moon. Once in orbit around the Moon, all four astronauts will use the lunar landing craft to descend to the surface of the Moon. Meanwhile, the Orion spacecraft will stay in lunar orbit. Once the astronauts’ mission is complete, they will return to the orbiting Orion vehicle using a lunar ascent module. The crew will use the service module main engine to leave lunar orbit and return to Earth. The Orion spacecraft will be able to carry more people and more cargo, equipment, and supplies than the Apollo spacecraft of the
1960s and 1970s. It will be able to carry everything the first mission requires, as well as extra materials and supplies for subsequent missions. This way, each mission will build on the ones before it. It would not take long for a permanent human residence on the Moon to be established. The Orion crew vehicle will also be capable of carrying crew and cargo to and from the International Space Station. It will even be part of the system of spacecraft used in Mars exploration missions.
WHY RETURN We’ve already been there, many people say, so why go back? It will cost billions of dollars. What will taxpayers get for their money? There are a number of answers to those questions. Some of the reasons are purely scientific, but others are very practical. Being able to explore and study the surface of the Moon for prolonged periods will allow scientists to discover what resources are there. Scientists want to find out if the Moon has oxygen and water necessary for life, as well as materials for construction and industry. These resources would be important for creating permanent, large-scale colonies on the Moon. A permanent presence on the Moon will let scientists explore farther and in more detail than they ever could during brief visits such as the Apollo program.
Scientists will also be able to research fundamental questions about the history of Earth, the solar system, and the universe— and about the role of humans in the universe. Scientists and engineers will be able to test technologies, systems, flight operations, and exploration techniques. Their findings will help with future missions to Mars and other places in the solar system. Pure scientific research on the Moon may result in discoveries that will benefit life on Earth, such as new medical techniques and medicines. Finally, largescale exploration of the Moon will require international cooperation and could expand Earth’s economy by creating the new industries and jobs needed to support such a large undertaking in space.
Although Orion’s overall design resembles the Apollo spacecraft, it takes advantage of twenty-first century advances in computers, electronics, life support, propulsion, and heat-protection systems. The United States is not the only nation interested in going to the Moon. Its rival this time, however, is China. China sent its first astronaut into orbit in 2003, becoming only the third country to put a human being into space. (Of course, many non-U.S. and non-Russian astronauts and cosmonauts have flown on U.S. and Russian spacecraft.) Chinese space officials set their sights on the Moon as one goal in an ambitious multistep space program. After robotic probes and initial human exploration, China plans to create permanent bases on the Moon.
NASA’s plans to reach Mars involve the use of the Ares V and Orion vehicles. But some scientists and engineers do not think that NASA has the most practical plan for exploring Mars. One such scientist is Robert Zubrin, whose Mars Direct plan appears to be the fastest, most economical project for reaching and exploring the Red Planet (Mars). Mars Direct would require the launch of an unmanned Earth Return Vehicle (ERV) directly from Earth’s surface to Mars. It would be launched by a heavy-lift booster about the same size as the Apollo Saturn V. It would land on Mars eight months later. The ERV would carry a cargo of hydrogen fuel, a small automatic chemical factory, and a compact nuclear reactor. The chemical factory would begin combining hydrogen with carbon dioxide from Mars’s atmosphere. This would create methane and oxygen. After ten months, 110 tons (100 metric tons) of methane and oxygen rocket propellants would accumulate.
To test equipment and techniques for the eventual exploration of Mars, a private organization called the Mars Institute has created a Mars base on Earth. It is located on Devon Island, far north of the Arctic Circle. The cold, barren, nearly lifeless island is about as close to Mars as anyone could find on this planet. Although no place on Earth is exactly like Mars, the Devon Island base allows the scientists there to develop special equipment and exploration techniques for future Martian explorers. They have been able to test
EARTH ground-penetrating radar surveys, which allow scientists to “see” beneath the surface of the ground. Field spectrometry helps scientists determine what elements make up rock and soil. These three-dimensional stereo cameras offer realistic threedimensional images. They have also done some test drilling into permafrost (a layer of permanently frozen water beneath the surface soil. On Mars the permafrost may be hundreds of feet thick). Tests of robotic helicopters, rovers, and space suits have also been done.
Twenty-six months after launching the ERV, a second spacecraft, the Mars Habitat Unit (MHU), would be boosted into space. The MHU would carry a crew of four to six astronauts. It would arrive at Mars six months later. Using the MHU as its base and living quarters, the crew would spend eighteen months exploring the Martian surface, using a small rover powered by excess methane and oxygen that the factory produced. At the end of the mission, the astronauts would use the fully fueled ERV to return to Earth, leaving their abandoned habitat for future explorers.
SPACE TOURISM The idea of traveling into space for fun—in orbiting space hotels, for example—has been around for a long time. Companies such as Space Adventures have been advertising space tourism. Some have even
proposed designs for their own spacecraft. But so far none of them has actually flown any passengers. The first tourists in space flew in the 1980s—and even these are borderline cases, depending on just how you define the word tourist. When U.S. senator Jake Garn flew on the space shuttle in 1985 and U.S. representative Bill Nelson in 1986, they had no real work to do as astronauts. They were, in effect, just along for the ride. However, as members of committees overseeing NASA funding, they weren’t exactly tourists either. Another U.S. senator who flew in the shuttle might be a little more deserving of the label space tourist. Mercury astronaut John Glenn returned to space in 1998 aboard the space shuttle, becoming, at the age of seventy-seven, the oldest human to fly in space. Also, a Japanese television reporter spent a week on the Mir space station, with his company picking up the $28 million price of his trip. But all of these space tourists so far were traveling into space for reasons other than sheer pleasure. They all had jobs to do, even it these were only for political or advertising reasons. Perhaps the first space tourist—and the luckiest one so far—was Helen Sharman, a British woman who won a 1991 trip to the Mir space station in a contest. MirCorp—a private company operating the Mir space station in its final years—saw space tourism as a way to help defray some of the costs of maintaining the station. They began advertising for people willing to pay several million dollars to spend a few days in the cramped quarters of the station. A U.S. millionaire, Dennis Tito, was the first to apply, but the decision to end the Mir space station came before he had his chance to visit it. Instead, he traveled to the International Space Station in 2001, where he stayed for a week. Tito was the first real space tourist in that he paid his own way and had no other agenda but his own pleasure.
Tito was followed in 2002 by South African Mark Shuttleworth. American Gregory Olsen went in 2005. Iranian American Anousheh Ansari went in 2006. In 2007 Charles Simonyi, one of the original employees of Microsoft, got his chance. All of these space tourists were wealthy people able to afford the multimillion dollar ticket into space. With the success of such ventures, numerous companies have been trying to establish regular space tourist flights. Most of these involve suborbital flights similar to the one Alan Shepard made in 1961, when he rode Mercury 3 into space. Instead of going into orbit, a suborbital flight would simply take passengers up to about 60 to 100 miles (97 to 160 km). They could experience a few minutes of weightlessness and see the black sky of space and the curvature of Earth. Even in the foreseeable future, however, with lower costs ranging from $20,000 to $200,000, this type of travel will still not be readily accessible to the average person. More ambitious companies plan to offer trips lasting a few days to several weeks in Earth’s orbit and even trips around the Moon, with a stopover at the International Space Station. Others plan to bypass the ISS by building their own space stations. Several Japanese companies have plans for private space stations—or space hotels— as does Hilton International and Richard Branson’s Virgin Galactic.
THE X PRIZE A big step toward the achievement of space tourism was the Ansari X Prize. It was named for Amir Ansari and his sister-in-law Anousheh, who contributed the prize money. The X Prize was originally established to encourage public enthusiasm for space exploration. It was modeled after the great aviation prizes of the 1920s and 1930s, such as the $25,000 Orteig Prize that inspired Charles Lindbergh to fly across the Atlantic Ocean. The
goal of the X Prize was eventually changed slightly. It was aimed at encouraging the development of low-cost spaceflight in the private sector, as well as the development of new imaginative technologies and techniques. To win the $10 million prize, the successful entrant would have to launch a reusable, piloted spacecraft into space (at least 62 miles [100 km]) twice within a two-week period. Government funding for the launches was forbidden. Twenty-six companies and individuals entered the contest. Some entrants developed spacecraft with fairly conventional designs. For instance, the Canadian Arrow resembled the German V-2 rocket of World War II. Other designs were very imaginative. SpaceShipOne, which had been created by Scaled Composites, a company operated by Bert Rutan, won the prize. Its two competitive flights were made on September 29, 2004, and October 4, 2004. Multibillionaire space enthusiast Paul Allen, one of the founders of Microsoft, provided funding for the project.
On June 21, 2004, SpaceShipOne became the first privately built and privately financed manned spacecraft to ever be launched into space.
Some people criticized the winning flight. Did the best spaceship design win the prize or did the best-funded spaceship design win? One of the major goals of the X Prize was to encourage the development of new technologies. It’s possible that designs superior to that of the winner may have lost simply because they weren’t able to find adequate funding. Building a spaceship is not cheap. But any way you look at it, the accomplishments of SpaceShipOne were remarkable. The spacecraft is on exhibit at the Smithsonian National Air and Space Museum in Washington, D.C. In spite of SpaceShipOne’s victory, some of the other competitors have continued work on their spacecraft. The Canadian Arrow, for instance, has conducted successful tests of its engine and has obtained permission from the Canadian government to create a launch site. SpaceShipOne may one day have some competition.
Plans for human presence in space include permanent colonies on the Moon and Mars. Many people have proposed ideas for space colonies. Space colonies would be enormous structures housing thousands of people who would live there permanently. People could live and even raise families in space colonies. Scientists have created many different designs for space colonies, but most are vast cylinders or rings more than 1 mile (1.6 km) wide. They slowly rotate to provide gravity for the inhabitants. Inside would be farmland, parks with lakes and streams, houses, schools, and factories. Other plans for humans in space include transforming planets such as Mars or Venus into worlds more like Earth. Humans could live on the surface unprotected by space suits or special habitats. This is called terraforming.
Mars might be terraformed by increasing its air pressure to a point where liquid water could exist on the surface. This might be accomplished by vaporizing the vast quantities of carbon dioxide ice found on and beneath the surface. Carbon dioxide is a heavy gas, and because of its weight, air pressure would increase rapidly. The gas would create a greenhouse effect by trapping solar heat on the surface, and the planet would grow warmer. With liquid water and warmer temperatures, plants would thrive and start producing oxygen. It may take hundreds or perhaps even thousands of years, but Mars would eventually become an Earthlike world on which people could live openly without needing space suits. NASA has plans for the human exploration of asteroids, perhaps to eventually mine them for their vast reserves of valuable minerals and nearly pure metals. Human explorers may also visit some of the planet-sized moons of Jupiter and Saturn. On Jupiter’s moon Europa, scientists will look for life in the great seas that exist beneath the ice. Saturn’s moon Titan has an atmosphere containing methane, a rocket fuel. This moon could become a way station between Earth and the outer limits of the solar system.
Voyages beyond the solar system are for the distant future. This is mainly because of the incredible scale of the distances involved. Apollo 11 took three days to travel the 250,000 miles (402,000 km) that separate Earth from the Moon. The distance to the nearest star—Alpha Centauri—is 6,750,000,000,000 times greater. Traveling at the speed of Apollo 11 (24,000 miles [38,624 km] per hour), it would take 20,250,000,000,000 days to make the one-way trip. That’s 55,479,452,054 years! To get to even the nearest star, spaceships would have to travel many times faster than Apollo 11. But greater speeds require greater
In the future, it will be possible to terraform planets such as Mars, turning them into worlds more like Earth. Here a future astronaut visits the surface of Mars’s tiny moon, Deimos. In the distance is a Mars that looks very different from the modern Mars. Many of its frozen, dusty deserts have been replaced by blue seas. Clouds drift through an atmosphere thick enough to support human life.
amounts of energy and fuel—or, more likely, entirely new types of propulsion. Ion engines, for example, have very low thrusts but can run continuously for months or years, eventually building speeds up to a significant fraction of the speed of light. The trip might then be reduced from thousands of years to decades. Many authors have proposed the generation starship, which would contain thousands, maybe even millions, of people. Entire families would be aboard, along with plants, animals, and everything else necessary for the existence of an entire culture. None of the people would ever see Earth again—nor would they ever see the starship’s destination. Only their descendants—their great-great-great-great grandchildren—would see it. The new worlds they discover will be their new homes—at least for those who want to leave the starship. Earth itself will seem far away and unreal, like a planet in a science-fiction story. To the descendants of the original starship crew, gazing at the new worlds beckoning them, Earth will be the stuff of dimly remembered legend and myth.
GLOSSARY alloy: two or more metals combined to form a new metal with characteristics different than the originals astronaut: a space explorer; in the United States, astronaut wings are awarded to anyone flying higher than 50 miles (80 km) in the atmosphere astronautics: the science of rocketry and space exploration atmosphere: the blanket of gases that surrounds a planet atmospheric friction: heat created by the molecules of gas in the atmosphere rubbing against a fast-moving object booster: a rocket used to accelerate an object; sometimes also called a launch vehicle combustion chamber: the part of the rocket motor where the fuel and oxidizer are combined and burned corona: the outermost atmosphere of the Sun cosmic rays: radiation of high penetrating power that originates in outer space. It consists partly of high-energy atomic nuclei. cosmonaut: the Russian equivalent of astronaut European Space Agency: a group of nations—including Austria, Belgium, France, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, and the United Kingdom—that has combined their resources for space development projects heat shield: a physical barrier that protects a spacecraft against the heat caused by atmospheric friction during reentry into Earth’s atmosphere launch vehicle: a rocket used to accelerate an object into orbit; also sometimes called a booster liquid fuel: rocket fuel in the form of a liquid, such as gasoline low Earth orbit: typically an orbit lower than 300 miles (480 km) meteor: the flash of light created when a meteoroid strikes Earth’s atmosphere; sometimes called a shooting star
meteoroid: a small metallic or rocky body in space nose cone: the end of a rocket opposite its engine that contains the payload or cargo orbit: to revolve around; the path a spacecraft follows as it circles a planet; the path a moon or planet follows as it circles a planet or the Sun oxidizer: a chemical that provides the oxygen necessary for the combustion of a fuel payload: the cargo carried by a rocket. This may be a weapon, instruments, or human beings. propellant: the material that is burned in a rocket motor or the material that is ejected from the nozzle to provide reaction satellite: any small object orbiting a larger one. The Moon is a satellite of Earth. skyrocket: a gunpowder rocket used in fireworks displays solid fuel: rocket fuel in solid form, which usually combines both fuel and oxidizer in one substance, such as gunpowder space station: a manned satellite circling Earth or another planet sunspot: an electromagnetic storm on the surface of the Sun. Because they are cooler than the surrounding area, they appear dark when seen from Earth. thrust: the forward-directed force developed in a rocket engine as a reaction to the high-velocity rearward ejection of exhaust gases velocity: the rate at which an object is moving
SOURCE NOTES 8 Marjorie Hope Nicholson, Voyages to the Moon (New York: Macmillan, 1960), 158–159. 21 Milton Lehman, Robert H. Goddard: Pioneer of Space Research (New York: Da Capo Press, 1988), 111. 31 Scientific American, “A Skyrocket Flying Machine,” March 29, 1913, 289. 42 NASA, “Apollo 11 Transcripts,” Kennedy Space Center, October 20, 2003, http://www-pao.ksc.nasa.gov/history/apollo/apollo-11/apollo11transcripts .htm (April 15, 2007). 58 Ibid. 60 NASA, “Mission Transcripts: Apollo 14,” Johnson Space Center, August 20, 2002, http://www.jsc.nasa.gov/history/mission_trans/apollo14.htm (April 15, 2007). 62 NASA, “Mission Transcripts: Apollo 15,” Johnson Space Center, April 20, 2002, http://www.jsc.nasa.gov/history/mission_trans/apollo15.htm (April 15, 2007). 64 NASA, “Where No Man Has Gone Before: A History of Apollo Lunar Exploration Missions,” 1989, http://history.nasa.gov/SP-4214/ch13-4.html (June 18, 2007).
SELECTED BIBLIOGRAPHY Gatland, Kenneth. The Illustrated Encyclopedia of Space Technology. London: Orion Books, 1989. Ley, Willy. Rockets, Missiles, and Men in Space. New York: Signet, 1968. Ordway, Frederick I., and Wernher von Braun. The Rockets’ Red Glare. Nelson, NZ: Anchor Press, 1976. ———. Space Travel: A History. New York: Harper & Row, 1985. Reynolds, David. Apollo: The Epic Journey to the Moon. New York: Harcourt, 2002. Winter, Frank. Rockets into Space. Cambridge, MA: Harvard University Press, 1990.
FOR FURTHER INFORMATION Books Crouch, Tom D. Aiming for the Stars: The Dreamers and Doers of the Space Age. Washington, DC: Smithsonian Institution Press, 2000. Kuhn, Betsy. The Race for Space: The United States and the Soviet Union Compete for the New Frontier. Minneapolis: Twenty-First Century Books, 2007. Miller, Ron. The Dream Machines: An Illustrated History of the Spaceship in Art, Science and Literature. Malabar, FL: Kreiger Publishing, 1993. ———. Robot Explorers. Minneapolis: Twenty-First Century Books, 2008. ———. Rockets. Minneapolis: Twenty-First Century Books, 2008. ———. Satellites. Minneapolis: Twenty-First Century Books, 2008. Spangenburg, Ray, and Kit Moser. Project Apollo. Danbury, CT: Franklin Watts, 2000. ———. Wernher von Braun: Out of the Fire, the Stars. Danbury, CT: Franklin Watts, 2007. Streissguth, Tom. Rocket Man: The Story of Robert Goddard. Minneapolis: TwentyFirst Century Books, 1995. Vogt, Gregory. Disasters in Space Exploration. Minneapolis: Millbrook Press, 2003. Magazines Ad Astra http://www.nss.org/ This is the official magazine of the National Space Society. Quest http://www.spacebusiness.com/quest/ This magazine is devoted to space history. Museums Kansas Cosmosphere and Space Center 1100 N. Plum Hutchinson, KS 67501 http://www.cosmo.org/visitorinfo/whyhutch.php
Kennedy Space Center State Road 405 Kennedy Space Center, FL 32899 http://www.kennedyspacecenter.com Pima Air & Space Museum 6000 E. Valencia Rd. Tucson, AZ 85706 http://www.pimaair.org/ San Diego Air & Space Museum 2001 Pan American Plaza Balboa Park San Diego, CA 92101 http://www.aerospacemuseum.org/ Smithsonian National Air and Space Museum 6th & Independence SW Washington, DC 20560 http://www.nasm.si.edu/ U.S. Space and Rocket Center One Tranquility Base Huntsville, AL 35805 http://www.spacecamp.com/museum/ Websites Discovery.com International Space Station http://www.discovery.com/stories/science/iss/iss.html This site gives viewers a good overview of the International Space Station. Encyclopedia Astronautica http://www.astronautix.com This website provides an online encyclopedia of spacecraft and space history. Mars on Earth http://www.marsonearth.org This is the official site of the Mars Institute’s Devon Island research station. NASA Home Page http://www.nasa.gov/ The official website of the National Aeronautics and Space Administration provides current mission photos and news.
NASA—International Space Station http://www.nasa.gov/mission_pages/station/main/index.html The official website of the International Space Station is updated daily. NASA Office of Policy and Plans http://www.hq.nasa.gov/office/pao/History/history.html This website provides general information about NASA and links to its other websites. Students for the Exploration and Development of Space http://www.seds.org This student-based organization promotes the exploration and development of space with programs, publications, membership, and discussion forums.
aircraft, rocket-powered, 28–40 Aldrin, Edwin "Buzz," 53, 54, 55–60, 60 Allen, Paul, 100–101 America Bomber, 35 Ansari, Amir, 99 Ansari, Anousheh, 99 Apollo, Project, 54–67 Apollo 7, 55 Apollo 8, 55 Apollo 9, 55 Apollo 10, 55 Apollo 11 moon landing, 54, 55–60 Apollo 12, 61 Apollo 13, 62 Apollo 14, 62 Apollo 15, 62–65 Apollo 17, 66–67 Apollo-Soyuz Test Project (ASTP), 68–69 Apollo spacecraft, 56 Ares I rocket, 93 Ares V rocket, 93–94 Armstrong, Neil, 52, 55–60 Atlas rocket, 42 Aurora 7, 46 Bean, Alan, 61, 78 Bell X-1 (Glamorous Glennis) aircraft, 36–38 Belyayev, Pavel, 47 Brand, Vance, 68 The Brick Moon (Hale), 72 California Institute of Technology, 37 Canadian Arrow spaceship, 100, 101 Carpenter, Scott, 43, 46 Carr, Gerald, 78–79 Ceman, Gene, 66–67 Cernan, Eugene, 55 Chaffee, Roger, 54 China, 96 Collins, Michael, 55–60 Columbia space shuttle, 88 Comet Kohoutek, 78–79 Comic History (de Bergerac), 9 command modules, 56 Conrad, Charles, 76, 78 Conrad, Pete, 61 Cooper, Gordon, 43 Crippen, Robert, 88 Crosby, Harry, 36 Cunningham, Walter, 55
de Bergerac, Cyrano, 6, 9 Dittmar, Heini, 32 Duke, Charlie, 66 EarthKAM experiment, 85 Eisele, Donn, 55 Ente (Duck), 30, 32 Enterprise space shuttle, 88 Explorer 1 satellite, 41 Frau im Mond (The Woman in the Moon) (film), 26 Friendship 7, 44 From the Earth to the Moon (Verne), 12–13 Gagarin, Yuri, 41 Galilei, Galileo, 7 Galileo space probe, 90 Gam, Jake, 98 Garriot, Owen, 78 Gemini, Project, 48–53 Gemini 3, 49 Gemini 6, 52 Gemini 7, 52 Gemini 8, 52 Gemini 9, 53 Gemini 12, 42, 52–53 Gemini spacecraft, 50 Gemini/Titan rocket, 59 Gibson, Edward, 78–79 Glenn, John, 43, 44–46, 98 Goddard, Robert H., 16, 19–23 Godwin, Francis, 6, 8–9 Grissom, Virgil "Gus," 43, 49–51, 54 Hale, Edward Everett, 72 Heinkel-176 aircraft, 32 hot-air balloon, 10 Hubble Space Telescope, 90 interstellar travel, 102–103 Irwin, Jim, 63–64 JATO motor units, 37 jet propulsion, 36–37 Kepler, Johannes, 8 Kerwin, Joseph, 76, 77, 78 Komet (Me-163), 32, 33 Kubasov, Valery, 68 Laika (dog), 28, 41 Lang, Fritz, 25–26
Law, F. Rodman, 31 Leonov, Alexei, 47, 68 Ley, Willy, 34 lifting-body research, 86 Lousma, Jack, 78 Lovell, James, 53 Magellan spacecraft, 90 The Man in the Moone (Godwin), 8–9 Mars, exploration of, 93, 96–97, 102 Mars Institute, 97 Mercury, Project, 42–46 Mercury 3, 43–44 Mercury 6, 44–46 Mercury/Atlas rocket, 59 Mercury/Redstone rocket, 58, 59 Mercury spacecraft, 45 Messerschmidt Me-163 rocket plane, 32 A Method of Reaching Extreme Altitudes (Goddard), 20 Mitchell, Ed, 62 Montgolfier, Étienne and Joseph, 9–10 moon: age and origins of, 68–69; Apollo 11 landing, 55–60; Apollo 8 lunar orbit, 55; exploration, 61–69; last landing, 66–67; lunar exploration base, 92–95; lunar roving vehicle (LRV), 63–64; politics in exploration, 42–43 MX-324 aircraft, 34, 36 NASA, 42 Nelson, Bill, 98 Newton, Isaac, 14 Nikolayev, Andrian, 46 Oberth, Hermann, 16, 19, 23–26 Olsen, Gregory, 99 Opel, Fritz von, 30, 86 Orion, 93–96 planetary exploration, 90, 91. See also Mars, exploration of Poe, Edgar Allen, 11 Pogue, William, 78–79 Potoˇcnik, Hermann, 70–71 Project Bumper (U.S. Army), 38 Die Rakete zu den Planetenräumen (Oberth), 23 Reitsch, Hanna, 32 rendezvousing and docking, 52–53 research, in space: moon exploration,
61–69, 95; space stations, 70, 78–80, 84–85 rocket development: Goddard's work, 19–23; liquid fuels, 17–18, 22–23, 25; in literature, 7, 9; multistage rockets, 27; Oberth's writings, 23–26; process, 14; solid fuels, 18; Tsiolovsky's theories, 16–19 Ruggieri, Claude, 29, 30 Rutan, Bert, 100–101 Sander, Friedrich, 30 Sänger spaceplane, 35, 39 Saturn 1B rocket, 54 Saturn V rocket, 54, 57, 58–59 Savitskaya, Svetlana, 73–74 Schirra, Walter, 43, 55 Schmitt, Harrison, 66–67 Scott, David, 52, 63–64 Sharman, Helen, 98 Shepard, Alan, Jr., 43–44, 49, 62 Shuttleworth, Mark, 99 Silver Bird, 35, 39 Simonyi, Charles, 99 Slayton, Donald "Deke," 43, 68 Somnium (Kepler), 8 Soviet Union, 40–41, 46–47, 67 space colonies, 101–102 space shuttle, 86–91 space stations: about, 70–71; International Space Station, 70, 83–85; Salyut space stations, 73–74; Soviet Mir space station, 70, 80–82, 98; in theory and writing, 70–72; U.S. Skylab space station, 70, 74–80 space suits, 47, 48–49 space tourism, 97–99 space travel stories, 8–15 space walks, 42 SpaceShipOne, 100–101 Sputnik 1, 40 Sputnik 2, 28, 41 Stafford, Thomas, 55, 68 Stamer, Friedrich, 30 Steel Pier Rocket Glider, 33 Surveyor 3 lunar probe, 61 Swan, William, 33 Tereshkova, Valentina, 46 terraforming, 101–102, 103 Tito, Dennis, 98 Titov, Gherman, 44 Tsiolkovsky, Konstantin, 16–19, 70 Tucker, George, 11
The Unparalleled Adventures of One Hans Pfaall (Poe), 11 V-2 rocket, 28, 33–34, 58 Valier, Max, 24, 30 Verne, Jules, 6, 11–15 von Braun, Werner, 33–34, 40, 72 von Kármán, Theodore, 37 Voskhod 1, 47 Voskhod 2, 47 A Voyage to the Moon (Tucker), 11 WAC-Corporal rocket, 38–39 Wan Hoo, 28, 29
Weitz, Paul, 76, 78 White, Ed, 42, 51, 54 women in space, 32, 46 World War II, 32–35 X-15 rocket plane, 39–40 X Prize, 99–101 XP-79 flying wing, 34 Yeager, Chuck, 36–38 Young, John, 49–51, 66, 88 Zubrin, Robert, 96
Ron Miller is the author and illustrator of about forty books, most of which have been about science, space, and astronomy. His award-winning books include The Grand Tour and The History of Earth. Among his nonfiction books for young people are Special Effects, The Elements, and the Worlds Beyond series, which received the 2003 American Institute of Physics Award in Physics and Astronomy. His book, The Art of Chesley Bonestell, won the 2002 Hugo Award for Best Non-Fiction. He has also designed space-themed postage stamps and has worked as an illustrator on several science fiction movies, such as Dune and Total Recall.
PHOTO ACKNOWLEDGMENTS All images were provided by the author except p. 100, Jim Campbell/Aero-News Network. Cover: NASA/JSC
For hundreds of years, scientists have sought and studied new worlds beyond Earth. Author Ron Miller describes the long, hard trek from the first tentative attempts to fly rocketpowered vehicles, to the first humans to brave traveling beyond Earth’s atmosphere, to the ex-
READ ALL THE BOOKS IN SPACE INNOVATIONS: Robot Explorers
plorers who left their footprints
in the soil of the Moon. This his-
tory of space exploration will
compel you to consider the future of our journey.