(HOUSTON) -- Potential orbital disaster was averted Tuesday, and the crew of the International Space Station didn't have to move an inch.
NASA had told the three astronauts aboard the ISS that they might have to duck into their Soyuz TMA-20 spacecraft because a six-inch piece of space junk was heading their way.
The debris was from the Chinese Feng Yun 1C satellite that was blown up in an anti-satellite test four years ago. Since then, the wreckage has been descending slowly, posing a threat to other satellites, as well as the ISS, as it does so.
Usually, NASA catches sight of space junk well in advance to give the ISS crew enough time to move the spacecraft slightly to avoid any collision that might put a hole in the floating station. However, that wasn't the case Tuesday, necessitating the warning to take shelter in the Soyuz.
Hours later, the red alert turned to green as flight controllers told commander Dmitri Kondratyev, flight engineer Paolo Nespoli and NASA flight engineer Catherine "Cady" Coleman that the probability of collision was nil and they could resume business as usual.
All this was good news for the crew because their replacements, who lifted off from Kazakhstan Monday, are due to dock with the ISS Wednesday evening.
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