• tal@lemmy.today
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    7 months ago

    I’d also add that, while it’s not the subject of the current discussion, non-nuclear kinetic anti-satellite weapons are bad enough; depending upon the altitude of the satellite, they can create long-lasting debris clouds.

    https://en.wikipedia.org/wiki/Kessler_syndrome

    The Kessler syndrome (also called the Kessler effect,[1][2] collisional cascading, or ablation cascade), proposed by NASA scientist Donald J. Kessler in 1978, is a scenario in which the density of objects in low Earth orbit (LEO) due to space pollution is numerous enough that collisions between objects could cause a cascade in which each collision generates space debris that increases the likelihood of further collisions.[3] In 2009, Kessler wrote that modeling results had concluded that the debris environment was already unstable, “such that any attempt to achieve a growth-free small debris environment by eliminating sources of past debris will likely fail because fragments from future collisions will be generated faster than atmospheric drag will remove them”.[4] One implication is that the distribution of debris in orbit could render space activities and the use of satellites in specific orbital ranges difficult for many generations.[3]

    The US did one non-nuclear anti-satellite test back when there were few satellites. It took decades for debris to deorbit. India did a relatively-safe, low-altitude one. We’d really, really like to not have especially high-altitude anti-satellite kinetic weapons used, because we don’t have a way to clean up the debris field.

    On 11 January 2007, China conducted an anti-satellite missile test in which one of their FY-1C weather satellites was chosen as the target. The collision occurred at an altitude of 865 kilometres, when the satellite with a mass of 750 kilograms was struck in a head-on-collision by a kinetic payload traveling with a speed of 8 km/s (18,000 mph) in the opposite direction. The resulting debris orbits the Earth with a mean altitude above 850 kilometres, and will likely remain in orbit for decades or centuries.[18]

    Absent the creation of some kind of new technology that can deorbit that debris, we’re going to be stuck with that one for generations to come.