Cape Canaveral (Florida): The space shuttle Endeavour is in the clear despite debris that peeled off during launch ahead of its docking with the International Space Station, NASA said Friday.
The debris was spotted after the shuttle took off Wednesday from the Kennedy Space Center, its sixth bid in recent weeks to reach the ISS after delays caused by weather woes and technical glitches.
"There is nothing that we have seen on the orbiter that causes any concern," space shuttle manager John Shannon told reporters.
The debris could be seen hitting the shuttle about two minutes into the flight in images broadcast on NASA TV.
"It didn`t hurt us apparently on this flight because it came off so late" in the ascent, Shannon said, adding that specialists from the US space agency would look at the issue more closely.
"We need to understand, since this looks like a new mechanism of shedding foam off the intertank... we need to understand that for the next flight," he said.
Earlier Thursday, NASA`s associate administrator for space operations, Bill Gerstenmaier, said the debris could be ice or foam that broke off from the external fuel tank.
"We had some foam loss events," he said. "You can clearly see, on the front part of the orbiter, some white indications where the tiles were dinged... We don`t consider those an issue for us, those are probably coating losses."
Endeavour astronauts used the shuttle`s robotic arm for what the space agency called "the standard flight day two inspection" of the reinforced carbon wing leading edge and nose cap.
Imagery experts on the ground will continue to assess images transmitted by the astronauts to determine the state of the shuttle`s thermal protection system, NASA said, adding that an early review showed only "a few minor dings" in some tiles due to the loss of small foam pieces from the external fuel tank.
During their first full day in space, the crew also inspected spacesuits that will be used during the five spacewalks planned during the mission.
The astronauts tested rendezvous equipment, installed a camera for the orbiter docking system and extended the docking ring that sits on top the docking system.
NASA has been cautious about conditions for the space shuttle`s exit and return since the shuttle Columbia blew apart some 20,000 meters (65,500 feet) above the Earth in 2003 as it was returning from a 16-day space mission to land in Florida.
A chunk of insulation that broke off from the shuttle`s external fuel tank during takeoff had gouged Columbia`s left wing heat shield, allowing superheated gases to melt the shuttle`s internal structure before it exploded, killing all seven astronauts onboard.
The six Americans and one Canadian aboard Endeavour are scheduled to reach the ISS at 1:55 pm (1755 GMT) on Friday, where they will complete the Japanese Kibo laboratory, a platform for astronauts to conduct experiments 350 kilometers (220 miles) above Earth`s surface.
The Endeavour mission aims to help fulfill "Japan`s hope for an out-of-this-world space laboratory," as the shuttle delivers state-of-the-art equipment to conduct experiments in the vacuum of space, NASA has said.
The ISS should be completed in 2010, also the target date for the retirement of the US fleet of three space shuttles.