• tal@lemmy.today
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    6 months ago

    SDI didn’t have nuclear weapons in space.

    Some proposals did include anti-ballistic-missile systems being stationed in space, but those had no nuclear payload.

    This recent thing about nuclear weapons in space is about use of nuclear weapons in an anti-satellite role, which the US believes Russia is banging on a system for. Problem is that those are indeed pretty good at messing up satellites, but also horribly non-specific and will clobber many, many satellites from many countries.

    https://en.wikipedia.org/wiki/High-altitude_nuclear_explosion

    The US did a test of a high-altitude nuclear explosion back when, not realizing the consequences, back when there were a tiny fraction of today’s electronic and satellite infrastructure, messed up terrestrial infrastructure and satellites, and realized that doing these was a very, very bad idea.

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

    Starfish Prime caused an electromagnetic pulse (EMP) that was far larger than expected, so much larger that it drove much of the instrumentation off scale, causing great difficulty in getting accurate measurements. The Starfish Prime electromagnetic pulse also made those effects known to the public by causing electrical damage in Hawaii, about 900 miles (1,450 km) away from the detonation point, knocking out about 300 streetlights,: 5  setting off numerous burglar alarms, and damaging a telephone company microwave link. The EMP damage to the microwave link shut down telephone calls from Kauai to the other Hawaiian islands.

    The explosion released roughly 10^29 electrons into the Earth’s magnetosphere. While some of the energetic beta particles followed the Earth’s magnetic field and illuminated the sky, other high-energy electrons became trapped and formed radiation belts around the Earth. The added electrons increased the intensity of electrons within the natural inner Van Allen radiation belt by several orders of magnitude. There was much uncertainty and debate[by whom?] about the composition, magnitude and potential adverse effects from the trapped radiation after the detonation. The weaponeers became quite worried when three satellites in low Earth orbit were disabled. These included TRAAC and Transit 4B. The half-life of the energetic electrons was only a few days. At the time it was not known that solar and cosmic particle fluxes varied by a factor of 10, and energies could exceed 1 MeV (0.16 pJ). In the months that followed, these man-made radiation belts eventually caused six or more satellites to fail, as radiation damaged their solar arrays or electronics, including the first commercial relay communication satellite, Telstar, as well as the United Kingdom’s first satellite, Ariel 1.

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

    If Russia uses nuclear weapons in space in an anti-satellite role in 2024, when there’s a lot of satellites up there, it’s probably going to dick up a hell of a lot of satellites from a hell of a lot of countries. Not to mention any terrestrial effects.

    • tal@lemmy.today
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      6 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.

    • subignition@kbin.social
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      6 months ago

      I was gonna make a dark joke about a silver lining, but I don’t think losing Starlink would be worth losing GPS.

    • ArcticAmphibian@lemmus.org
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      6 months ago

      You’re totally right - SDI wasn’t nukes in space. Just pointing out the similarities in concept and reaction:

      • Threaten to put advanced military tech and/or weapons of some sort in space.
      • Reveal very little about what is actually being currently done and what is just plans/theory.
      • (to be seen) Use it as a negotiation tool for favorable arms-reduction or other treaties.