This “space race” began in 1957, when Soviet Union launched into orbit Sputnik, the first artificial satellite, or man-made object that orbits a larger body in space. Four years later, the Soviets sent the first person, Yuri Gargarin, into space.

The United States soon surpassed the Soviets. In 1969, the United States Apollo program landed the first humans on the moon. Both superpowers also explored the military uses of space and sent spy satellites to orbit Earth.

Today, the United States and Russia still have the largest space programs and have even cooperated in joint space ventures. Several other countries have also developed space programs, including China, Pakistan, Japan, France, Britain, and both North Korea and South Korea.

Science in Space

In the decades since Sputnik and Apollo, nations have launched rockets to other planets and beyond. Robotic space vehicles have penetrated the mists of Venus and the rings of Saturn, landed on Mars, and circled the moons of Jupiter. Space missions have pursued a variety of goals. Some take scientific measurements, release permanent satellites or telescopes, or gather information about the composition and formation of the universe itself. On manned space missions, astronauts conduct medical or biological experiments.

Increasingly, nations have worked together to explore space. Russia, the United States, Canada, Japan, and several European countries developed the International Space Station (ISS). Construction on the ISS began in 1998 and was completed in 2010.

The ISS has served as a space laboratory, allowing scientists to observe space, conduct research, and develop new space-related technologies. China has its own space station, and plans are underway for other joint stations. Future plans include set up a colony on Mars as well as searching for signs of life in other galaxies.

In the 21st century, space travel and exploration is no longer the business of only governments. Several private companies now launch rockets into space. One California company founded in 2002 has the goal of enabling people to live on other planets.

Space technology has benefited life on earth. Dozens of new products, developed for use in space, are today used on Earth. They include liquid-cooled garments, hang gliders, metalized plastics for use in construction and other areas, foam cushions used in helmets and for medical needs, a blood pump that can be used as a temporary heart, and a lightweight breathing system for firefighters.

Artificial Satellites

Thousands of artificial satellites orbit Earth every day. They are used in one of three ways: communications, observation, and navigation. They have both military and non-military uses

Communications satellites, for example, relay information that can be used for television, telephone, and high-speed data transmission. Maintaining stationary orbits over specific points on Earth's surface, communications satellites can transmit phone messages or television pictures anywhere on Earth. Linked to cell phones or computers, they allow people, separated by thousands of miles, to communicate instantly.

Observation satellites provide data to scientists, weather forecasters, and military planners. A satellite can receive transmissions from underwater detectors and track the size and strength of tsunamis. Navigation satellites, or global positioning satellites (GPS), beam precise locations to ships, ground vehicles, airplanes, and even hand-held devices.

Photo of an astronaut floating in the space station, taking photographs of earth from the window.

An Italian astronaut takes photographs on board the International Space Station in June 2013. Scientists at the station must deal with the long-term effects of weightlessness while they conduct research and develop new technologies.

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Table of Contents

World History Topic 1 Origins of Civilization (Prehistory–300 B.C.) Topic 2 The Ancient Middle East and Egypt (3200 B.C.–500 B.C.) Topic 3 Ancient India and China (2600 B.C.–A.D. 550) Topic 4 The Americas (Prehistory–A.D. 1570) Topic 5 Ancient Greece (1750 B.C.–133 B.C.) Topic 6 Ancient Rome and the Origins of Christianity (509 B.C.-A.D. 476) Topic 7 Medieval Christian Europe (330–1450) Topic 8 The Muslim World and Africa (730 B.C.-A.D. 1500) Topic 9 Civilizations of Asia (500–1650) Topic 10 The Renaissance and Reformation (1300–1650) Topic 11 New Global Connections (1415–1796) Topic 12 Absolutism and Revolution Topic 13 The Industrial Revolution Topic 14 Nationalism and the Spread of Democracy (1790–1914) Topic 15 The Age of Imperialism (1800–1914) Topic 16 World War I and the Russian Revolution (1914–1924) Topic 17 The World Between the Wars (1910–1939) Topic 18 World War II (1930–1945) Topic 19 The Cold War Era (1945–1991) Topic 20 New Nations Emerge (1945–Present) Topic 21 The World Today (1980-Present) United States Constitution Primary Sources 21st Century Skills Atlas Glossary Index Acknowledgments