Discovery's astronauts began their first full day of work in space Wednesday with a carefully orchestrated inspection of the shuttle's wings and nose to detect any damage that may have occurred during liftoff.
NASA officials said Tuesday an object that may have been a 1 1/2-inch piece of thermal tile appeared to break off from the Discovery's belly during liftoff. Also, a large object — perhaps a piece of foam insulation — seemed to fly off from the external fuel tank, NASA flight operations manager John Shannon said.
Officials stressed it was too early to say whether there was any danger to the shuttle or its crew. Wednesday's highly sensitive search, which was expected to take about seven hours, uses a sensor attached to a 50-foot extension of the shuttle's robotic arm. The astronauts must be careful not to bump the equipment against the shuttle's fragile exterior.
Flight director Paul Hill, who worked in Houston's Mission Control as astronauts began maneuvering the arm, considers the inspections among the most hazardous of the new procedures put in place since the 2003 Columbia tragedy.
"If we make contact with the orbiter while we're doing this, I'm looking for another job," Hill said in the months leading up to the 12-day mission.
Once the initial inspection is complete, three of the seven astronauts planned to remove the 50-foot extension and use a camera attached to the robotic arm to inspect tiles near the crew cabin and tail.
Also Wednesday, astronauts Stephen Robinson and Soichi Noguchi tested tools and equipment they'll use during three spacewalks. They also planned to prepare the shuttle's airlock for the astronauts to exit when they arrive Thursday at the international space station.
During the spacewalks, the pair will test new repair techniques for the shuttle's tiles and delicate carbon panels; replace a gyroscope, which helps steer the international space station; and install a storage platform on the station.
Commander Eileen Collins and Pilot James Kelly repositioned the shuttle early Wednesday and planned to redirect it a second time to make sure the vehicle is positioned correctly to catch up with the international space station for docking. When the astronauts awoke Wednesday, the shuttle trailed the station by 5,500 miles.
Another task Wednesday was for the crew to deploy an antenna, which allowed them to send televised images from the sweeping scans of the shuttle's wings and nose to the ground. NASA officials said they also received data from 176 sensors placed on the shuttle wings to detect any debris strikes.
Analysis of the data, television and other images was under way at Johnson Space Center early Wednesday.
The crew spent most of Tuesday turning their "rocket into a Winnebago," said astronaut Daniel Tani, who flew aboard the shuttle in 2001.
"It is a big reconfiguration," Tani said of the work Discovery's crew had to do to turn the shuttle from rocket into orbiting vehicle.
Two weather planes and more than 100 cameras documented Discovery's trip to orbit. NASA wants to document any sign of flying debris that could threaten the shuttle.
"There is no question that we have more data now than we have ever had before," Flight Director LeRoy Cain told The Associated Press. "We are going to see things when we look and so one of the things we have worked really hard on is to make sure we understand what are we looking at."
The new cameras and inspections are part of safety procedures put in place for NASA to return to space following the grounding of its shuttle fleet after the breakup of space shuttle Columbia in 2003.
Columbia was brought down by a suitcase-size piece of foam insulation, which broke off the external fuel tank during liftoff and struck one of the shuttle's wings. The resulting gash allowed hot gases into the wing during Columbia's return to Earth 16 days later on Feb. 1, 2003.
All seven astronauts aboard died as the shuttle disintegrated over Texas.
NASA officials said they could barely make out the foam strike in the photographs because of the poor quality of the images they had.
The new cameras and lasers will provide the space agency with more detailed images than it has ever seen before, Shannon said. But it is unclear if the debris spotted so far represents anything out of the ordinary.
Shannon said the tiles on NASA's shuttle fleet have sustained thousands of dings over the years.
"One of the things that is going to be critical for us is to give the experts opportunity and time to bring the data in, review it, analyze it and bring it forward and have that in a cohesive way, so that we don't have folks running off in different directions without the full story," Cain said.