Leading Article: Will the celestial soap opera take off again?

THE PATRONS of exploration are notoriously fickle. Sir Walter Raleigh paid with his life when his expeditions in competition with the Spanish grew unfashionable and his reputation flagged. The glory days when he returned from South America bearing the potato were easily forgotten.

Likewise Nasa, that 20th-century equivalent of the Elizabethan adventurer, seemed destined for the scrapyard in these post-Cold War days. Successful Apollo missions and walks on the Moon had become obscured by the Challenger shuttle disaster in 1986 and the initial failure of the Hubble, an expensive, but - when put to the test - myopic, space telescope.

And then, thankfully, the events of the past month changed everything, as Nasa suddenly rehabilitated itself. Crisp television pictures of astronauts fixing Hubble with their screwdrivers restored the support of a hostile American public. Yesterday it was revealed that the rescue of what had become a byword for space disaster has proved a triumph of human ingenuity. Pictures from Hubble show that its vision of the universe has been corrected.

Welcome though this achievement is, the American public should not to be seduced into funding expensive follies. Into this category falls Nasa's proposal for a giant, permanently manned space station. Unmanned expeditions are usually cheaper and yield just as much knowledge. It is said that if Hubble had been launched on unmanned rockets instead of the shuttle, scientists could have had seven space telescopes for the price of the recently repaired one. cw0

Nasa, which has been profligate in the past, should not be let off the financial leash. Astronauts in space may result in a fascinating celestial soap opera for television viewers, but sending people into orbit must be shown to be cost-effective.

Britain, an albeit niggardly subscriber to the European Space Agency, Nasa's Hubble partner, should play its part in encouraging sound investment. But the American public will be the main losers if their government does not ensure that a rehabilitated Nasa keeps a toehold on financial reality.