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by tim-tday19 hours ago |
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upvoteby Polizeiposaune19 hours ago|
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It won't be centuries.

starlink satellites are in low orbits and will deorbit in a few years at most if bricked; to stay in orbit, they use ion thrusters to counter drag from the very uppermost reaches of the atmosphere.

https://ai-solutions.com/newsroom/why-starlink-is-lowering-s...

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upvoteby titzer18 hours ago|
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When satellites smash into each other at high velocity, they explode. Some of that debris will end up in higher orbits and linger.
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upvoteby Polizeiposaune16 hours ago|
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Some of the debris from a collision may end up in an orbit with a higher apogee, perigee will necessarily still be at or below the altitude of the last collision and will be subject to some of the same low-orbit aerodynamic drag that starlink satellites experience; passes through lower altitudes will apply drag that will first drop the apogee and will then eventually cause the debris to reenter.
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upvoteby audunw16 hours ago|
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How can it linger in a higher orbit. Maybe some of the debris gets a kick which increases its velocity, but you need two velocity boosts to circularise the orbit, no? So I figure at worst you get an elliptical orbit which will still decay
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upvoteby moralestapia15 hours ago|
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Nope, if it goes up it will go down even faster.

Orbits are about speed. Two things colliding cannot have debris coming out at a faster velocity than either of them.

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upvoteby zwily19 hours ago|
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Kessler is much less of a problem at their altitude (480km). Debris has too much drag and would get pulled down too quick to have a sustained Kessler situation. It's possible, but very very unlikely at that altitude.
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upvoteby dualvariable14 hours ago|
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You could still generate a mess for 5-10 years at that altitude. Even if it self-clears you still destroy the constellation and deny access to LEO for years.
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upvoteby inemesitaffia3 hours ago|
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That's not Kessler syndrome though. Is a cascade
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upvoteby mlindner11 hours ago|
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Kessler syndrome relies on two key provisions:

1. Orbiting objects never try to avoid each other.

2. They're in high enough orbits that atmospheric drag is not a significant factor such that debris can last decades or centuries.

Starlink fails both as they constantly maneuver and they're in low orbits that are constantly cleaned by the atmosphere.

And I'd add that "kessler syndrome" is actually a statistical process, not a rapid sudden cascade of satellites crashing into each other. It takes years to decades for it to actually "happen". It's not something that can be caused by military action either.

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upvoteby NetMageSCW19 hours ago|
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Stop trying to make Kessler syndrome a thing - it was never a thing, it isn’t a thing, it will never be a thing.

It is just pearl clutching by those too afraid of modern life. Gravity wasn’t a documentary.

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upvoteby hackeraccount5 hours ago|
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Hey! I think I saw you on Ars. Or maybe someone there copied and pasted this?
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upvoteby bell-cot5 hours ago|
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Back in the day, "Kessler syndrome" was a fairly good way to articulate the fears of many scientists - whose delicate one-off "flagship" scientific research satellites had huge costs and lead times, if things started going wrong up there.

And overall, today's space powers are much more careful about not making messes in orbit.

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upvoteby serf19 hours ago|
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a new hot take spotted : newtonian physics isn't a thing.

let's see how well the freeways work once we stop cleaning up after the accidents.

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upvoteby NetMageSCW19 hours ago|
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I see you haven’t read the paper. How long do you think Kessler syndrome is projected to take? How long do you think natural clearing of debris at Starlink’s altitudes is?
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upvoteby panick21_18 hours ago|
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Freeways are not 3 dimensional and they don't have an automatic cleanup that cleans up things within a pretty short time. Also area we are talking about is fucking gigantic. Also accidents are going to be very rare as sats deorbit themselves end of live and even if they break and can't move anymore, other sats that can still move can evade them.
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upvoteby micromacrofoot19 hours ago|
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I mean it might be a thing in 100 years but we're not even close now
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upvoteby WillAdams16 hours ago|
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Which means that we need to act responsibly and plan ahead now so that it is not a thing 100 years hence.
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