Security ... think about it!
When seven astronauts board the Atlantis shuttle on 11 May for an 11-day mission to repair the ailing Hubble telescope, they will be aware of the formidable task ahead. Five spacewalks to replace broken parts. No space station nearby as a refuge. Earth more than 350 miles below. But the significance of the Hubble repair mission goes much further than the technical challenges facing the crew. This mission amounts to the swansong of the shuttle, the culmination of a 30-year, $170bn (£115bn) programme to consolidate humankind's mastery over space.