Space exploration the process of traveling into space and learning about the conditions in space and on stars, planets, and their moons, This is done by two means:


Unmanned Satellites and Space Probes

The first artificial satellite, Sputnik I, was launched by the Soviet Union on October. 4, 1957. Explorer I, the first American satellite, was launched on January 31, 1958. These orbited the earth. It took the launching of space probes that went out into space to get more specific information about planets and other space phenomena.

The United States and the Soviet Union launched about fifty space probes to explore the moon. They were of several types:


The Soviet Luna series were the first to accomplish each objective in the 1960s with the Luna program, including orbiting the moon.

While the American program followed behind the Soviet program, it generally revealed more scientific information with the Ranger and Surveyor programs. The Ranger program took many pictures and Surveyor program involved soft landings with television cameras placed on the moon. The Lunar Orbiter later followed which got pictures from both sides of the moon and pictures of Earth from the moon. These missions were also in preparation for a manned moon landing in the Apollo program.

Interplanetary Probes

.The US Mariner and Magellan programs studied Venus and Mars. The Soviet Venera series also studied Venus. Much was learned about the planets' surfaces and atmospheres. The American Viking program had spacecraft land on Mars. Along with the Soviet Union various European efforts via the European Space Agency and the Japanese launched efforts.

Voyagers 1 and 2, which were launched in 1977, explored Jupiter, Saturn, Uranus, and Neptune to explore all four planets. Passing as close as 3,000 miles or 4,800 kilometers to each planet's surface, the Voyagers discovered new rings, magnetic fields, and took photographs of these planets and their moons. The joint US-ESA probe Cassini, launched in 1997, will explore Saturn, its rings, and some of its moons upon arriving in 2004.


Manned Space Exploration

Human spaceflight started with suborbital flights. Later goals reached were the launching of a single astronaut in orbit, the launching of several astronauts, the meeting and docking of two spacecraft, spacecraft, making a lunar orbit, and landing of an astronaut on the moon.

The first person in earth orbit was a Soviet cosmonaut, Yuri Gagarin, in Vostok 1 on April 12, 1961.

The American Mercury program had its first orbital success in February, 1962, when John Glenn circled the earth three times. In October, 1964, three Soviet cosmonauts were launched in a Voskhod spacecraft. During the second Voskhod flight in March 1965, a cosmonaut left the capsule to make the first spacewalk.

The first launch of the Gemini program, carrying two American astronauts, occurred a few days after the Soviet spacewalk. The United States made its first spacewalk during Gemini 4. Later flights established techniques for meeting and docking in space. The first actual docking of two craft in space was achieved in March, 1966, when Gemini 8 docked with a crewless vehicle. In October, 1967, two Soviet Cosmos spacecraft performed the first automatic crewless meeting and docking. Gemini and Voskhod were followed by the American Apollo and the Soviet Soyuz programs.

The Apollo Program

The Apollo program was the biggest scientific project in history. Its goal was to put a man on the moon and to learn more about the moon. There were 17 Apollo flights and six moon landings. Apollo 8 was the first space ship to orbit both the earth and the moon. On July 20, 1969, astronauts Neil A. Armstrong and Edwin Aldrin, Jr., stepped on the moon as Michael Collins, orbited the moon in the command ship. Altogether, there were 17 Apollo missions and 6 lunar landings. Apollo 15 had the first use of the Lunar Rover, a space jeep. he Apollo Lunar Surface Experimental Package.

Ten Apollo moon flights were launched by the three-stage Saturn V rocket . The Apollo spacecraft weighed 44 tons and stood nearly 60 feet or 20 meters high. It had three sections were the command, service, and lunar modules. In earth's orbit, the lunar module was removed from its storage and placed on the command module. Once in lunar orbit, two astronauts moved to the lunar module, which then loosed from the command module and went down to the moon's surface.

The Soyuz Program was the name of the Soviet Union's manned lunar program which did not enjoy the success of the Apollo program.

Space Stations

Skylab was a research space station that orbited the earth. The main capsule was launched and then the crews arrived later in another spacecraft. Skylab was a working space station for a little less than a year. The first crew reached Skylab in May, 1972. The purpose of Skylab was to get information about the earth in a wide range of topics and to test man's reactions to long stretches of time in space.

The Mir as well as the International Space Station which was a joint effort of the United States, Russia, Japan, Canada, Brazil, and ESA as well as astronauts and cosmonauts from Afghanistan, Austria, Britain, Bulgaria, France, Germany, Japan, Kazakhstan, Syria, and the United States worked on Mir alongside their Russian astronauts. Putting together of the International Space Station began in December, 1998, and will be done in 2004

The Space Shuttle

shuttle animation

After the Skylab space station fell out of orbit in 1979, the space shuttle was launched in 1981. . The shuttle itself returns to earth in a guided glide, landing either in California or in Florida.

The shuttle can put a payload of 20 tons or 18,000 kilograms in earth's orbit. The Galileo probe, created to investigate Jupiter's upper atmosphere, was launched from the space shuttle. Astronauts conduct experiments, repair space equipment, etc..

The explosion of the Challenger shuttle in 1986 was due to cold launch conditions led to the failure of a rubber O-ring that then ignited the fuel tank. After redesign, the shuttle goes up about every other month with four spacecraft used.




Animated row of rockets


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