A new National Research Council report may revive plans to send a spacecraft to explore Pluto and its neighborhood. Even though NASA eliminated funding for it in its 2003 budget, the report recommends that the agency give top priority to a major Pluto mission. The Washington, D.C.–based council issued the NASA-sponsored study on July 11.
Pluto is the only planet in the solar system that a spacecraft hasn't directly observed. Astronomers continue to debate whether Pluto actually is the solar system's smallest planet or the largest member of the Kuiper belt, a reservoir of primitive, icy objects beyond the orbit of Neptune (SN: 6/9/01, p. 360: Nine Planets, or Eight?).
Pluto is now rapidly receding from the sun, and some astronomers have argued that if a spacecraft isn't launched within the next few years, the planet will be completely frozen over by the time a probe arrives. Current spacecraft would take about a decade to get to the planet.
The panel that compiled the findings says that to understand how life developed in the solar system and the nature and origin of the planets, NASA should launch small-scale robotic spacecraft to intriguing parts of the solar system every 18 months.
The National Research Council panel recommends a mission to bring back samples from the south pole of Earth's moon. The site includes a mammoth impact basin that might hold clues to the formation of the Earth-moon system and could provide a source of water for space travelers. The panel also urges NASA to give priority to exploring Jupiter's moon Europa, which might harbor some type of life in an ocean under its icy surface. The report also supports a controversial plan by NASA to develop nuclear power sources for space travel.
Cowen, R. 2001. Nine planets, or eight? Science News 159(June 9):360. Available to subscribers at [Go to].