Second chance for Hubble

摘要

After a tentative start to operations in 1990, the Hubble Space Telescope (HST) has become a success story for Nasa, so much so that the US space agency has announced a U-turn on its decision to stop servicing it. Hubble was effectively scrapped after the Space Shuttle Columbia disaster in 2003, when the ship broke up on re-entry into the Earth's atmosphere and all seven astronauts aboard were killed. Nasa ruled out another Hubble service mission, saying it would be too dangerous. But the decision was unpopular inside and outside the agency, especially after the significant successes and benefits the programme had already delivered.