Checks carried out in space on the underside of the space shuttle Endeavour revealed a gouge in the vital heat shield insulation. It’s thought a piece of ice may have hit the shuttle during its trip into orbit. It’s not yet clear how important the damage is. NASA’s Mission Management chairman John Shannon said: “We had one debris event where we saw a streak, potentially a spray of some material from the underside of the vehicle, at 58 seconds. That was tracked by radar, and the ballistic co-efficient, or how that particle was tracked, looked more like ice than foam”. NASA isn’t panicking yet; there will be more checks over the weekend, and repairs can be carried out in space. Meanwhile the astronauts are on board the International Space Station, preparing for the first space walk. The shuttle is expected to stay in orbit for another week.