The launch of space shuttle Endeavour from Kennedy Space Center in Florida, which had been scheduled for 7:17 A.M. (Eastern Daylight Time) today, has been postponed due to a leak of hydrogen at the launch site, NASA announced early this morning. With days needed for repair, the soonest available launch opportunity for the orbiter is now June 17, but the space agency plans to launch a pair of lunar spacecraft that day from nearby Cape Canaveral Air Force Station, which poses a scheduling conflict.

In a statement, NASA said the Endeavour launch to the International Space Station was "on hold due to a leak associated with the gaseous hydrogen venting system outside the external fuel tank." A similar leak postponed the launch of space shuttle Discovery in March, which eventually lifted off safely four days later.

The space agency said that mission managers would meet Sunday to discuss future launch options.

Photo of Endeavour at Kennedy Space Center: NASA TV