Rachel_Sandford
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In September 1991, NASA launched the Upper Atmosphere Research Satellite (UARS). It was meant to study climate change on Earth, and it has provided the conclusive evidence we now know about CFCs. Now dead, having run out of fuel in 2005, which is when it completed its mission, the $750 million (£468 million) satellite is set to breach the Earth's atmosphere in late September or early October of this year.
Usually, scientists steer dead satellites into “graveyard orbit” or into the ocean. Unfortunately, the UARS doesn't have enough fuel for this maneuver. So it will fall uncontrollably towards Earth. The agency estimates that pieces of the six tonne satellite can land anywhere in the six continents, with the danger zone being narrowed down to areas between 57 degrees north and 57 degrees south of the Equator, having a debris footprint 500 miles long. Most of the satellite will burn after entering the Earth's atmosphere, but about half a tonne, or 544kg of metal will survive.
The agency has also issued official statements about the matter, saying “It is too early to say exactly when UARS will re-enter and what geographic area may be affected, but NASA is watching the satellite closely.” They are currently tracking the satellite on a weekly basis, and later on, will track it on a daily basis from the Johnson Space Centre in Houston, Texas.
According to NASA, the risk to public safety is small. The agency's rule is that satellites should have a one-in-10,000 chance of hitting humans upon re-entering. UARS was launched before this rule was set in place, however, and pieces from the satellite have a one-in-3,200 chance of hitting someone. In fact, throughout history, there have “been no confirmed reports of any injury resulting from re-entering space objects.”
Gene Stansbery, NASA's orbital debris chief said: “Things have been re-entering the earth ever since the dawn of the Space Age; to date nobody has been injured by anything that's re-entered. That doesn't mean we're not concerned.”
“If you find something you think may be a piece of UARS, do not touch it. Contact a local law enforcement official for assistance.” Even if no hazardous material was left in the satellite, NASA would still prefer that people not try to keep any of the debris for safety reasons.
UARS plummeting towards Earth won't be the first time space objects have fallen towards earth, nor is it the largest. In 1979, the 91-tonne Skylab fell towards earth, and in 2001, the 123-tonne Russian space station, Mir, also fell. In both situations, no one was hit by the falling debris. However, the US Space Surveillance Network has already revealed that there is more than 22,000 objects measuring about 10cm or more above earth. The National Academy of Sciences says scientists have lost control over the space environment, and according to the Pentagon, the amount of space debris floating above us may cause collisions between satellites, destroying communications networks. The US Defense Department Space Posture Review painted a similar picture, saying the number of abandoned rockets, satellites, and shrapnel threatens the $250 billion (£174bn) space services industry.
Usually, scientists steer dead satellites into “graveyard orbit” or into the ocean. Unfortunately, the UARS doesn't have enough fuel for this maneuver. So it will fall uncontrollably towards Earth. The agency estimates that pieces of the six tonne satellite can land anywhere in the six continents, with the danger zone being narrowed down to areas between 57 degrees north and 57 degrees south of the Equator, having a debris footprint 500 miles long. Most of the satellite will burn after entering the Earth's atmosphere, but about half a tonne, or 544kg of metal will survive.
The agency has also issued official statements about the matter, saying “It is too early to say exactly when UARS will re-enter and what geographic area may be affected, but NASA is watching the satellite closely.” They are currently tracking the satellite on a weekly basis, and later on, will track it on a daily basis from the Johnson Space Centre in Houston, Texas.
According to NASA, the risk to public safety is small. The agency's rule is that satellites should have a one-in-10,000 chance of hitting humans upon re-entering. UARS was launched before this rule was set in place, however, and pieces from the satellite have a one-in-3,200 chance of hitting someone. In fact, throughout history, there have “been no confirmed reports of any injury resulting from re-entering space objects.”
Gene Stansbery, NASA's orbital debris chief said: “Things have been re-entering the earth ever since the dawn of the Space Age; to date nobody has been injured by anything that's re-entered. That doesn't mean we're not concerned.”
“If you find something you think may be a piece of UARS, do not touch it. Contact a local law enforcement official for assistance.” Even if no hazardous material was left in the satellite, NASA would still prefer that people not try to keep any of the debris for safety reasons.
UARS plummeting towards Earth won't be the first time space objects have fallen towards earth, nor is it the largest. In 1979, the 91-tonne Skylab fell towards earth, and in 2001, the 123-tonne Russian space station, Mir, also fell. In both situations, no one was hit by the falling debris. However, the US Space Surveillance Network has already revealed that there is more than 22,000 objects measuring about 10cm or more above earth. The National Academy of Sciences says scientists have lost control over the space environment, and according to the Pentagon, the amount of space debris floating above us may cause collisions between satellites, destroying communications networks. The US Defense Department Space Posture Review painted a similar picture, saying the number of abandoned rockets, satellites, and shrapnel threatens the $250 billion (£174bn) space services industry.
