A little bit of engineering (Несколько текстов для зачёта), страница 31

Mars will be visited by a succession of landers and orbiters as part of NASA’s Discovery Program, of which the Mars Pathfinder lander was a part. The program suffered setbacks in 1999 that jeopardized NASA’s goal of retrieving a sample of Martian rocks and soil in 2003 and bringing it to Earth. Although NASA planned future missions to Mars, the missions may face delays as engineers work to ensure they do not lose more spacecraft to human error or inadequate testing.

The Discovery program also includes the Near Earth Asteroid Rendezvous mission (NEAR). This spacecraft entered orbit around the asteroid Eros in 2000. In 2004 a spacecraft called Stardust, launched on February 7, 1999, is scheduled to fly past Comet Wild 2 (pronounced Vilt 2) and gather samples of the comet’s dust to bring back to Earth (see Comet).

Jupiter’s moon Europa is also likely to receive increased scrutiny, because of strong evidence for a liquid-water ocean beneath its icy crust. Among the missions being studied is a lander to drill through the ice and explore this suspected ocean. As with Mars, scientists are especially eager to find any evidence of past or present life on Europa. Such investigations will be difficult, but the discovery of any form of life beyond Earth would undoubtedly spur further explorations.

Saturn will be visited by the Cassini orbiter in the summer of 2004. The spacecraft is to deploy a probe called Huygens that will enter the atmosphere of Saturn’s largest moon, Titan, in December 2004. During its trip to the surface, Huygens will analyze the cloudy atmosphere, which is rich in organic molecules.

NASA is also considering orbiters to survey Mercury, Uranus, and Neptune. Pluto, the only planet that has never been visited by a spacecraft, is the target for a proposed Pluto Express mission. A pair of lightweight probes would be launched at high speed, reaching Pluto and its moon Charon as early as 2010.

NASA’s New Millennium program is aimed at creating new technologies for space exploration and swiftly incorporating them into spacecraft. In its first mission, the Deep Space 1 spacecraft used solar-electric propulsion to fly by an asteroid in July 1999 and was scheduled to visit comet Borelly in 2001.

NASA also plans a number of orbiting telescopes, such as the Chandra X-Ray Observatory, an X-ray astronomy telescope launched from the space shuttle in 1999. Another program, called Origins, is designed to use ground-based and space-borne telescopes to search for Earthlike planets orbiting other stars.

Space exploration experts have long hoped that as international tensions have eased, an increasing number of space activities could be undertaken on an international, cooperative basis. One example is the International Space Station. In 1998, however, countries and agencies such as Japan and the European Space Agency (ESA) began to reassess their commitments to space exploration because of economic uncertainty. The transportation system for this mission may involve Russian space hardware, such as the Soyuz spacecraft.

In addition to the economic savings that could result from nations pooling their resources to explore space, the new perspective gained by space voyages could be an important benefit to international relations. The Apollo astronauts have said the greatest discovery from our voyages to the Moon was the view of their own world as a precious island of life in the void. Ultimately that awareness could help to improve our lives on Earth.