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Encyclopedia > Kessler Syndrome

The Kessler Syndrome is a scenario, proposed by NASA consultant Donald J. Kessler, in which the volume of space debris in Low Earth Orbit is so high that objects in orbit are frequently struck by debris, creating even more debris and a greater risk of further impacts. The implication of this scenario is that the escalating amount of debris in orbit could eventually render space exploration, and even the use of satellites, too prone to loss to be feasible for many generations. The National Aeronautics and Space Administration (NASA) is an agency of the United States Government, responsible for that nations public space program. ... Space debris or orbital debris, also called space junk and space waste, are the objects in orbit around Earth created by man that no longer serve any useful purpose. ... A low Earth orbit (LEO) is an orbit in which objects such as satellites are below intermediate circular orbit (ICO) and far below geostationary orbit, but typically around 350 - 1400 km above the Earths surface. ... Space exploration is the physical exploration of outer space by both manned and unmanned spacecraft. ... An Earth observation satellite, ERS 2 For other uses, see Satellite (disambiguation). ...


The Kessler Syndrome is especially insidious because of the "domino effect." Any impact between two objects of sizable mass will create additional shrapnel debris from the force of collision. Each piece of shrapnel now has the potential to cause further damage, creating even more space debris. With a large enough collision (such as one between a space station and a defunct satellite), the amount of cascading debris could be enough to render Low Earth Orbit essentially impassable. A cascading failure is failure in a system of interconnected parts, where the service provided depends on the operation of a preceding part, and the failure of a preceding part can trigger the failure of successive parts. ...


Every satellite, space probe and manned mission has the potential to create space debris. As the number of satellites in orbit grow and old satellites become obsolete, the risk of a cascading Kessler Syndrome becomes greater.


The Kessler Syndrome presents a unique problem to human space travel. Space debris is very difficult to deal with directly, as the small size and high velocities of most debris would make retrieval and disposal impractically difficult. Given thousands of years, most debris in Low Earth Orbit would eventually succumb to air resistance in the rarefied atmosphere and plunge to the Earth. If magnetically susceptible, the debris could fall in a few decades due to the drag of the Earth's magnetic field. View of Jupiters active atmosphere, including the Great Red Spot. ...


To minimise the chances of damage to other vehicles, new vehicles and satellites are frequently required to demonstrate that it can be safely disposed of at the end of its life, for example by use of a controlled atmospheric reentry system.


Fortunately at the most commonly used Low Earth Orbits residual air drag helps keep the zones clear. Altitudes under 300 miles will be swept clear in a matter of months.


See also

Space debris or orbital debris, also called space junk and space waste, are the objects in orbit around Earth created by man that no longer serve any useful purpose. ... Ablation cascade is a term used for a possible catastrophic orbital event. ... The 2007 Chinese anti-satellite missile test was a detonation of a missile conducted by the Peoples Republic of China on January 11, 2007. ...

References

  1. D.J. Kessler (1991). "Collisional Cascading: The Limits of Population Growth in Low Earth Orbit". Advances in Space Research 11: 63. 

External links

  • Mathematical Modeling of debris flux
  • New York Times: Orbiting Junk, Once a Nuisance, Is Now a Threat

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