Chinese space junk collided with a small Russian satellite in January, damaging it in a collision that has again highlighted the problem of manmade extraterrestrial clutter.
The Colorado-based Center for Space Standards and Innovation (CSSI) found that Russia's Ball Lens in the Space (BLITS) spacecraft was hit by piece of orbital debris from China's Fengyun 1C satellite, destroyed in 2007 as part of a Chinese anti-satellite test, Space.com reported.
It is only the second time that an active spacecraft has collided with another artificial object in space, Space Daily wrote.
A US communications satellite was hit by a defunct Russian military satellite in February 2009.
However, it highlights the growing threat that space junk poses to activities in low-Earth orbit (LEO), experts have said.
Space.com quoted Brian Weeden, a technical adviser with the Secure World Foundation, an organization dedicated to the peaceful use of outer space, as saying:
"It's not the wake-up call — we've had too many of those already. Many satellites in LEO [low-Earth orbit] are having to maneuver on a regular basis to avoid threatening close approaches with debris. This is just one more data point that shatters the myth of the 'big sky' theory regarding space activities and shows that debris is one of the most pressing threats satellite operators in LEO have to contend with."
NASA estimates that the LEO "cloud" contains 500,000 objects bigger than a marble and 22,000 larger than a softball.
According to the European Space Agency website, debris levels have increased 50 percent in the last five years.
NASA investigators looked into the possibility that space debris may have caused the break up of the Space Shuttle Columbia upon reentry Feb. 1, 2003 over Texas.
Space Safety Magazine recently cited a report from the Inter-Agency Space Debris Coordination Committee as saying that the debris situation in LEO may be reaching a catastrophic "tipping point," known as the Kessler Effect.
It was NASA's Donald Kessler who in 1978 first predicted that the cloud of objects in LEO would become so dense that it would result in collisions between objects that would in turn create space junk and thus cause more collisions.
Such a cascade of collisions would then render LEO unsafe for satellites for several generations.
Space.com wrote that debris from the Fengyun 1C, which was demolished after exceeding its service life, has long posed a threat to satellites and crewed spacecraft.
Meanwhile, it remained unclear whether Russia's 16-pound BLITS satellite was simply damaged or rendered inoperable in the Jan. 22 collision with a piece of junk weighing only about .08 grams.
Russian scientists Vasiliy Yurasov and Andrew Nazarenko, of the Institute for Precision Instrument Engineering in Moscow, reported a "significant change" in the BLITS' orbit to CSSI.
Legal action against China is unlikely, Space.com wrote, even though China could technically be held responsible for the impaired state of the satellite under the 1972 Convention on International Liability for Damage Caused by Space Objects.