Scientists have always known that the Hubble Space Telescope--one of the world's most popular and productive scientific instruments--wouldn't be kept in orbit forever. Although it's not supposed to be serviced past 2004, many researchers are pressing NASA to extend its life. So the agency has decided to ask a high-powered group of astronomers and astrophysicists to share the burden of determining how and when to shut down Hubble.
Launched in 1990, Hubble requires human assistance to remain in orbit and generate data. The final servicing mission, scheduled for late 2004, would allow Hubble to function through the close of the decade. But scientists worry that a data gap could open up before the scheduled launch of Hubble's successor, the James Webb Space Telescope, in 2011. So they're pushing NASA not to abandon Hubble just yet.
The panel assessing this is headed by Princeton University's John Bahcall. He chaired a much-praised 1991 National Academy of Sciences panel that set a long-term vision for astronomy. He will be joined by five other distinguished colleagues, including Nobelist Charles Townes of the University of California, Berkeley, and Martin Rees of the University of Cambridge, U.K. The panel will hold a public meeting in Washington, D.C., on 31 July, and it is also soliciting opinions from the community. "This is a very hot potato issue," says Bahcall. "This is not a job to take on to win friends."
Hubble's fate is complicated by the Columbia disaster, which puts even the next servicing mission into question. David Black, director of Houston's Lunar and Planetary Institute, fears that any Hubble mission may be seen as too risky, because the shuttle astronauts would be unable to rendezvous with the space station in an emergency.
Some of the strongest advocates for continued Hubble operations are at the Space Telescope Science Institute in Baltimore, Maryland. "Hubble is right now the highest impact scientific mission at NASA," says Steven Beckwith, the institute director. "It's a living mission, and we have not tapped its full potential yet." But both sides agree that the new panel, officially the Hubble Space Telescope-James Webb Space Telescope Transition Plan Review Panel, will be highly influential. "They have both the wisdom and the freedom to ask good questions," adds Beckwith.