Astronauts Inspect Space Shuttle Heat Shield

HOUSTON - Astronauts aboard NASA?s shuttle Discovery began their first full day in orbit Wednesday with a heat shield inspection as they head toward an orbital rendezvous with the International Space Station (ISS).

Discovery?s seven-astronaut crew wielded a laser sensor-tipped extension of their shuttle?s robotic arm to scan heat shield panels along the orbiter?s wing edges and nose cap one day after rocketing spaceward from the Kennedy Space Center in Florida.

?I personally did not see anything of significance,? said NASA?s lead STS-120 shuttle flight director Rick LaBrode, adding that a complete analysis of the heat shield survey is still under way.

Commanded by veteran shuttle flyer Pamela Melroy, Discovery?s STS-120 astronaut crew launched on a 14-day construction mission that NASA has described as its most challenging to date. The shuttle astronauts will deliver Harmony, a vital hub-like module that will anchor future laboratories to the ISS, during the first of five planned spacewalks outside the orbital laboratory.

Later in the flight, the STS-120 crew will also move a massive solar power segment to the port-most edge of the station?s backbone-like main truss and unfurl its expansive arrays. Discovery is also ferrying U.S. astronaut Daniel Tani to the ISS, where he will replace fellow NASA spaceflyer Clayton Anderson as a member of the station?s three-person Expedition 16 crew.

Discovery mission specialist Stephanie Wilson, the lead robotics operator for STS-120, oversaw today?s heat shield inspection, which was primarily aimed at scanning the reinforced carbon-carbon (RCC) panels that line the orbiter?s wing edges and nose cap. Melroy, shuttle pilot George Zamka and mission specialists Scott Parazynski, Paolo Nespoli also participated in the RCC panel survey.

Before Discovery?s launch, an independent NASA engineering group called for the replacement of three of the spacecraft?s 44 wing-mounted RCC panels due to apparent defects in their exterior coating. Mission managers cleared the shuttle for flight, but modified today?s inspection to get a clearer view of the heat shield panels.

?We are slowing down just one of the scans, one pass on each of the wings, just to give us an opportunity to get a little bit higher-fidelity imagery with our laser scans,? LeRoy Cain, who chaired NASA?s STS-120 Mission Management Team for the mission?s launch.

On Earth, analysts will study the imagery and video from today?s inspection to determine the health the Discovery?s heat shield. They will also study images from Discovery?s launch and a detailed photographic survey of the orbiter?s heat-resistant tiles, to be conducted by the ISS crew before the shuttle docks at the station, as well.

Mission managers said about six pieces of foam insulation broke free from Discovery?s fuel tank during its Tuesday launch, but all of them occurred too late in the ascent to pose a risk to the shuttle. NASA has kept a close watch on fuel tank debris during liftoff and shuttle heat shield integrity since the 2003 Columbia accident.

LaBrode said he was confident that a glitch with Discovery?s computer network, which could delay the delivery of some digital images from today?s inspection, would be resolved soon. The shuttle?s crew worked to fix the glitch during the survey.

NASA?s Mission Control here at the Johnson Space awoke Discovery's crew today at 1:38 a.m. EDT (0538 GMT) with the song ?Lord of the Dance? by John Langstaff.

?Good morning Discovery, and a special good morning to you Pam,? NASA astronaut Shannon Lucid told the crew from Mission Control. ?Welcome to your first full space day for the STS-120.?

?Thanks Shannon, that was one of my favorite songs from the Christmas Rebels,? Melroy said. ?Thanks to my husband Doug. I love you.?

Melroy and her STS-120 crewmates are due to arrive at the ISS on Thursday, with docking scheduled for 8:35 a.m. EDT (1235 GMT).

NASA is broadcasting Discovery's STS-120 launch and mission operations live on NASA. Click here for mission updates and NASA TV from SPACE.com.

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