Discovery launch put off until late Friday

NASA on Thursday put off the planned launch of the space shuttle Discovery for a third time to give engineers more time to study tests on a liquid hydrogen valve, the space agency announced. The shuttle's liftoff -- originally set for Tuesday -- has been put off until 11:59 p.m. Friday, mission managers said. Two scheduled launch times were put off Tuesday, one due to bad weather and the other when a hydrogen valve failed to show up as closed on controllers' displays. More

(Source: CNN - Aug 27)