What could be sillier than throwing away the Hubble Space Telescope, one of the most productive instruments in the history of science? That was the message from most speakers at last week's public meeting on the telescope's fate (see page 603). Yet there was dissent, mostly from people whose projects face delays if Hubble gains an extended life beyond its planned demise in 2010.

Foremost among those projects is the James Webb Space Telescope (JWST). Despite being conceived as the Next Generation Space Telescope, it is not Hubble's successor. It will observe in the near- and mid-infrared, where Hubble is not so competitive. In a decadal review of priorities published in 2000, US astronomers asked for a large infrared space telescope, not for Hubble 2 — and that's just what NASA is giving them. But circumstances have changed. The JWST was due to launch in 2007, but now will not arrive until 2011 at the earliest. Nervous astronomers have come to see the value of a bird in the hand.

At last week's meeting, Bruce McCandless, a former astronaut who helped to place Hubble in orbit in 1990, suggested that major instruments should not be decommissioned until user demand drops. Other satellites, such as the International Ultraviolet Explorer and the Compton Gamma Ray Observatory, were arguably past their prime when they were shut down. But observing time on Hubble looks set to remain as coveted as ever for many years to come.

Unfortunately, NASA can't pay for the JWST and other future projects without retiring Hubble, unless Congress and the White House decide to loosen the purse strings. NASA's science managers have already been rewarded with budget increases for their relative financial rectitude, while those in charge of the space station have been punished for their profligacy. Astronomers can make a strong case for further cash injections into NASA's science programme, to delay Hubble's demise without sacrificing the JWST's timetable.

In today's harsh economic climate, there's no guarantee of success. But that shouldn't stop NASA earmarking small sums for preliminary studies of future Hubble instruments, to preserve the option of upgrading the telescope again after 2005 if the cash is forthcoming.