Introduction to Space Exploration - Robotic Space Explorers

Space programs centered around human explorers are very expensive. It is far cheaper to build and send mechanized (robotic) spacecraft to do the exploring. During the 1960s the Apollo program dominated the spotlight, but it was not the only space exploration project in operation.

Beginning in 1962 NASA launched robotic probes that flew by Mercury, Venus, or Mars and beamed back photographs of them. During the 1970s more sophisticated robotic spacecraft landed on Mars or were sent to fly by the outer planets (Jupiter, Saturn, Uranus, Neptune, and Pluto). These missions were given heroic names, including Mariner, Viking, and Voyager.

In 1990 a robotic spacecraft called Magellan set down on the surface of Venus. It was named after Ferdinand Magellan (c. 1480–1521), the Portuguese explorer who led the first sailing expedition to circle the world. In 1995 a spacecraft named after Galileo Galilei began orbiting Jupiter.

Interplanetary exploration is tough, even for machines. During the 1990s NASA lost three robotic spacecraft on their way to Mars. Another one safely made it to the Martian surface. In the early 2000s NASA had two more successful missions to Mars. The first was called Mars Odyssey and included a probe that went into orbit around the planet in 2001. Three years later the Mars Exploration spacecraft put down two remarkable rovers on Mars named Spirit and Opportunity. As of March 2004 these two rovers continued to explore the surface of Mars.

Not all space exploration requires long-distance travel. Advances in computers and telescopes have allowed scientists to do a lot of exploring with robotic spacecraft stationed nearby Earth. These high-technology machines take photographs, measure radiation waves, and collect data on solar phenomena.

The latest generation of robotic explorers can even snatch samples of radioactive particles and dust in outer space and return them to Earth. The first of these new explorers was scheduled to come back in late 2004.