By Richard Hartley-parkinson Last updated at 11:51 AM on 11th July 2011 Nasa is monitoring a piece of 'Russian' space junk that looks likely to come dangerously close to the International Space Station during a planned space walk tomorrow. The debris is heading towards the station, where Atlantis yesterday docked on its final mission. Scientists are still trying to work out how big the object is and how close it will come to Atlantis. Some believe it originated from a defunct Russian satellite that is orbiting Earth. LeRoy Cain, mission management team leader, said he hopes the space junk will keep a safe distance and as they observe its trajectory throughout today, they will be able to work out how close it will come.
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Nasa is trying to work out if the junk comes from a defunct Russian satellite
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It is scheduled to pass the space station at around 5pm GMT on Tuesday
It is estimated that there are 370,000 pieces of space junk floating in @placeholder's orbit.