NASA delays Endeavour's launch

NASA called off yesterday’s launch of the space shuttle Endeavour to the international space station because of danger from an unsecured Russian supply ship.

The unmanned Russian ship arrived at the space station on Wednesday but failed to attach itself properly. NASA feared the forces exerted by the arriving shuttle would cause the supply ship to wobble, damaging the space station.

Endeavour was supposed to drop off two Americans and one Russian for a six-month stay on board the space station, and bring back the three men who have been living up there since August.

The launch was scrubbed with just hours left in the countdown, and was put off until at least this evening while space agency managers tried to diagnose the problem and decide what to do. But by late yesterday, managers had ruled out a launch today and were debating when to make the next attempt.

Fixing the problem will almost certainly require a spacewalk.

The countdown continued under unprecedented security, with fighter jets, attack helicopters and military personnel in camouflage on guard against terrorist attacks. A 35 mile no-fly zone on small aircraft was established around the launch pad.

The supply ship arrived at the space station with more than a ton of food, fuel, clothes and other supplies. But the eight docking latches that are supposed to hold it securely did not click into place.

Based on a fuzzy video of the docking, flight controllers suspect a one foot cable - or something else entirely - is preventing the ship from latching on. But no one seemed to know where the cable came from.

‘‘As different people look at the video, some say, ‘Oh, there it is,’ and they clearly point to a piece of debris. And other people say, ‘I’ve no idea what you’re pointing to,’’’ said Nasa’s Jim Van Laak, a space station manager.

Russia has proposed that the two cosmonauts aboard the space station go out on a spacewalk as early as Monday to remove the cable.