NASA astronauts are preparing for launch on a mission to fix the ailing Hubble space telescope. The shuttle Atlantis is due to lift off this evening on the fifth and final mission to the telescope before it is taken out of service. And they have their work cut out. During their 11 day mission they have to install two new cameras, six positioning gyroscopes and batteries, and repair two broken instruments.David Leckrone, the NASA Senior Project scientist said: “I really do think we, NASA, humankind, are on a fast track to, in my lifetime, to detect an Earth-like planet or more than one Earth-like planets around other stars and detect their atmospheres. And I really think that’s going to happen. I think we have set the stage for that and when that happens I am going to look back and be proud of the little, tiny steps that Hubble took in that direction.” Since it was put into orbit in 1990, Hubble has provided astronomers with data unimaginable from Earth-bound observatories, including revelations about the expansion of the universe and the Big-Bang theory. NASA hopes this overhaul will keep Hubble operating until 2014, by which time its successor should be in service.