Shuttle heads toward station, NASA studies problem

CAPE CANAVERAL, Fla., June 10 (Reuters) The space shuttle Atlantis closed in on the International Space Station today as NASA experts studied whether a damaged thermal blanket at the rear of the orbiter needed repair.

Stitches holding the blanket that forms part of the shuttle's heat protection may have ripped during yesterday's launch, causing a few inches of the thick material to peel away from Atlantis, NASA said.

''It's not a great deal of concern over it right now, but there's a lot of work to be done'' to study the tear, said deputy shuttle program manager John Shannon.

If experts determine the damage poses a threat to the safety of the shuttle, which encounters high temperatures when it returns to earth, Shannon said a spacewalking astronaut could repair it.

Three spacewalks are already planned for the flight and there is room in the schedule for more if needed, he said.

The peeled-back blanket was one of very few problems found so far on Atlantis, which is scheduled to rendevous with the space station on tomorrow.

The shuttle is transporting new segments to be attached to the station, including a solar array that will generate additional electricity needed as the station is expanded.

A small piece of insulating foam was seen missing from the shuttle fuel tank in photographs taken by the shuttle crew, but was not thought to be large enough to be of concern, Shannon said.

''The vehicle was very clean going uphill,'' he said in NASA-speak in a briefing at Johnson Space Center in Houston.

While engineers on the ground looked at photos of the blanket, the shuttle crew used a sensor-laden robotic arm to check the ship's wings for damage from blastoff.

CLOSE SCRUTINY OF IMAGES, DATA Astronauts Patrick Forrester, Steven Swanson and Lee Archambault, in an inspection now mandatory on shuttle flights, slowly panned the imagers over the leading edges of the wing and nosecose, sending back data and images that will be pored over on Earth.

They also zoomed in on the blanket tear to give NASA experts a close look.

NASA has been concerned about foam insulation falling off the fuel tank during launch ever since it lost the shuttle Columbia and seven astronauts in 2003.

Debris hitting the craft can damage the delicate heat panels and tiles that protect it from the scorching plunge through the atmosphere to return to Earth.

Columbia's wing was damaged by debris during launch and the spaceship was torn apart over Texas as it headed to landing.

Atlantis' launch, the fifth since the fatal accident, heightened attention on the tank because it needed extensive repairs to fix hail damage.

The shuttle was on the launch pad being prepared for a mid-March takeoff when a freak storm on Feb. 26 dropped hailstones on the ship, forcing NASA to delay it the mission for three months.

Last evening, Atlantis was about 6,400 km behind the space station and catching up at the rate of 1,141 km per orbit. It was scheduled to link up with the station at 0108 IST Monday and spend a week there.

NASA has a dozen more shuttle flights scheduled to complete construction of the 100 billion dollar orbital complex, a project of 16 nations.

The US space agency also wants to fly two missions to store spare parts aboard and to service the Hubble Space Telescope one last time before all three of its remaining orbiters are permanently grounded in 2010.

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