(HOUSTON) -- Space shuttle Atlantis, which safely docked with the International Space Station on Sunday, may face a close call with space junk early this week.
NASA has been notified that space debris will pass close to the space station/space shuttle on Tuesday, when the one spacewalk of this mission is scheduled. Mission Management Team Director Leroy Cain says it is too early to tell what, if any, evasive maneuvers are required. They have teams working around the clock to determine whether there's a real threat to the spacecraft.
The space shuttle would use its thrusters to move the space station out of harm's way, if necessary. Mission managers also have an imaginary safety zone set up around the two spacecraft.
"There is a lot of junk in orbit, there are a lot of objects being tracked," Cain said. "Fortunately we have a good process for dealing with it, we have a number of spent rocket bodies, and over time these things drag down from their original orbits."
The news came after an emotional, complicated rendezvous by Atlantis with the ISS, the last the two are scheduled to ever make. With shuttle Commander Christopher Ferguson at the controls, Atlantis pulled up beneath the station, did a slow back flip so that station astronauts could photograph its heat shield for possible damage, and then came in for docking.
The astronauts' job was complicated by a computer glitch. One of Atlantis' five main computers unexpectedly turned itself off during the rendezvous. NASA said it did not threaten the mission, but there might be trouble if a second computer quit.
"Atlantis arriving," called out space station astronaut Ron Garan. "Welcome to the International Space Station for the last time."
"And it's great to be here," Ferguson said.
Concerning the debris, there is no word yet on the size of the object, or if it is related to a close call two weeks ago, when the ISS crew had to shelter in their Russian Soyuz return capsules. That debris came within 1,000 feet of the space station.
NASA expects any maneuvers would be made Monday night and doesn't know yet how this will affect Tuesday's spacewalk.
The item NASA is tracking is from a Soviet 1970s rocket -- its orbital debris catalog number is 4664. The incident from two weeks ago caught NASA by surprise, and mission managers are uneasy about having 10 people on board the space station with only two Soyuz escape vehicles that seat three crewmembers each.
The space shuttle can't undock and escape that quickly and its size and sensitive heat shield make it a vulnerable target.
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