HOUSTON ? Thevital heat shield protecting NASA's space shuttle Endeavour appears in goodshape after launch despite three apparent debris hits, mission managers said Thursday.
Cameras mountedto Endeavour's external tank caught nine pieces of foam insulation break offduring liftoff, three of which appeared to strike the orbiter, said JohnShannon, STS-118 mission management chairman, during a briefing here at theJohnson Space Center. None of the impacts are believed to have causedsignificant damage, he added.
Shannonsaid one fragment popped free about 24 seconds after Endeavour'sWednesday launch and appeared to hit the end of the shuttle's aft-mountedbody flap.
A secondpiece separated about 58 seconds into the flight and appeared to cause a sprayof material on Endeavour's starboard wing. The third fragment separated nearthe three-minute mark, much too late to cause significant damage.
But thefoam incidents did not appear to be severe in images relayed to Earth byEndeavour's fuel tank camera, Shannon said.
"Iwould tell you that the picture was extremely underwhelming," Shannon saidof the apparent starboard wing hit. "The report initially was that you gota spray of debris from this area and of course that brings up images ofColumbia?this was not even remotely of the same magnitude."
Abriefcase-sized piece of foam fell from the shuttle Columbia's fuel tank during its 2003 launch,piercing the heat shield and leading to the loss of the orbiter and itsseven-astronaut crew.
DuringEndeavour's rendezvous with the International Space Station (ISS) at 1:53 p.m.EDT (1753 GMT) tomorrow, astronauts aboard the orbital laboratory will takedetailed photographs of the three impact points before the orbiter docks. Theimages, as well as data taken from the shuttle crew's heatshield inspection today, will be analyzed by engineers on Earth.
Commandedby veteran astronaut Scott Kelly, the STS-118 crew's majortasks include attaching a starboard (S5) truss spacer to the ISS,delivering fresh cargo and shuffling space station components to make way forfurther construction.
Endeavour'screw awoke to an alarm last night, which turned out to be the failure ofan oxygen tank pressure sensor. Liquid oxygen is used in Endeavour's fuel cellsto help generate electricity for the shuttle, but must gently boiled into gasby heaters when power is needed.
"Withthe failure we're going to have to use manual heater control. The automaticheater control is not functional on that tank," said Matt Abbott, NASA's STS-118lead shuttle flight director.
Because ofthe faulty sensor, the astronauts will need to turn on the heaters via flightdeck controls about once every hour to keep feeding the shuttle's electricity-generatingfuel cells.
"It'sjust a matter of flipping the switch on, flipping the switch off," Abbottsaid of the procedure, which should not impact the crew's busy ISS constructionschedule during their 11-to-14-day mission. "It will require somebabysitting."
Endeavour'sSTS-118 mission marks the first time in space for three mission specialists,including teacher-astronaut BarbaraMorgan as well as Alvin Drew and Tracy Caldwell. Shuttle pilot CharlieHobaugh and mission specialists Dave Williams and Rick Mastracchio round outthe crew.
The astronauts awoke early Thursdayto the song "Where My Heart Will Take Me" by Russell Watson, thetheme to "Star Trek: Enterprise," chosen for Mastracchio.
"They'rehaving a great time," Abbott said of the rookies, adding that every one ofthe crew members looks like "they're having a ball."
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- VIDEO: Endeavour's STS-118 Mission Profile
- Complete Space Shuttle Mission Coverage