Weather concerns again forced a cancellation of the launch of the Discovery. There is another launch attempt scheduled for Tuesday.
NASA decided to "stand down" Sunday in order to top off on-board supplies of liquid hydrogen, used as fuel in powering the shuttle's electric system during flight. The hydrogen, despite being cooled several hundred degrees below zero Fahrenheit, boils off as it sits in fuel cells on the launch pad.
By using Monday to reload hydrogen, engineers will be able to attempt launches both Tuesday, at 2:38p.m., and Wednesday, if necessary. Also, while bad weather is predicted for Monday, some improvement is expected Tuesday. At no time Sunday were the chances of launch rated any better than 30 per cent.
Shuttle officials have cautioned for a week that mid-summer afternoons in central Florida are generally rainy. NASA, however, must launch Discovery in the afternoon so it will be on course to intercept the space station yet remain in daylight after lift-off so cameras can photograph the external fuel tank when it is jettisoned half a world away. Damage caused by fragments of foam insulation from the external tank caused the shuttle Columbia to disintegrate over Texas in 2003, and have remained the program's chief concern ever since.
Discovery's 12-day mission to the international space station will focus on replenishing the station, repairing station machinery and testing new shuttle equipment. In addition, the shuttle will deliver European Space Agency astronaut Thomas Reiter to the station to join Commander Pavel Vinogradov and Flight Engineer Jeffrey Williams, bringing the station's complement back up to three for the first time since the Columbia disaster.
I joked tonight that they postponed the inevitable death of the astronauts until Tuesday. I sure hope it remains a joke. I am seriously concerned about the safety of this mission and I’ve lost a lot of faith in NASA.