Nasa’s space shuttle Discovery has blasted off from Cape Canaveral in Florida in the first such mission since the Colombia disaster of 2003.The launch had been postponed from July 13 because of a glitch with a fuel sensor. No such problems showed up in pre-flight tests. With seven crew members on board, Discovery hurtled upwards into blue skies above the Kennedy Space Centre. The two rocket boosters which give the shuttle its initial power separated in a textbook manouevre two minutes after take-off. Seven minutes later Discovery reached its planned preliminary orbit and cut off its three main engines. It is a 12-day mission for the crew, which is headed by Commander Eileen Collins. They will test new safety measures and repair kits, plus bring equipment and supplies to the International Space Station.