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by sidewndr46 263 days ago
I don't know the specifics of starlink satellites but a rupture of any pressurized line has a chance of causing an unintended ascent. Thankfully in most cases the satellite is stabilized, so there is a good chance the satellite just gets a huge amount of rotational velocity added to it with no increase in altitude.
3 comments

You seem to have a misunderstanding of basic orbital mechanics. That wouldn't cause an "ascent" like with an airplane or something. There will be a change in orbital parameters but a permanent change in orbital altitude isn't really possible in that scenario.
Whatever you do to launch an object higher, it will return to its original altitude once per orbit. If you want to stay high you first have to boost up and then you have to boost again half an hour later, which will happen just about never with debris.
You'd still have an eccentric orbit intersecting some "higher" ones periodically, no?

Certainly less dangerous than something "going the wrong way" in a given orbital shell, but not sure if it's completely negligible either.

For the lucky few pieces that launch at just the right angle, they'll spend a few months or years intermittently intersecting higher orbits.

But almost all the debris will either stay close to the original orbit or burn up within hours.

It's a mass problem. Instead of imagining the gravity well as something moving away from earth out into the vacuum of space, think of it as a ball that needs to be rolled uphill - even if you give it a huge burst of energy, it's not going to go as far as you think from that one big push, and it's still going to roll back downhill. In order to make it out of the gravity well, you need a lot of focused, continuous energy over huge distances.

There are other factors, too - imagine you're trying to send a penny around the entire equator of the earth, and think of the largest possible explosion you could subject it to without vaporizing it. A stick of dynamite could launch a penny only around a half mile's distance around the equator, assuming ideal conditions, which is about .0025% of the circumference of the earth, which is 10% of the distance between the earth and the moon, and the moon is about 25% of the distance from which earth's gravity stops being a significant factor.

If you carefully deployed a large number of well timed series of dynamite sticks precisely located so that each blew up perfectly beneath the penny at its apex following each previous explosion - you'd need 150-300 sticks to get the penny out past the edge of the effective gravitational well, the point at which other factors in the solar system have the dominant influence - it'd effectively leave earth and start falling toward the sun. At any point closer to earth than that, it will slowly and inexorably return back to earth, reaching up to 25,000 mph before vaporizing itself in the atmosphere (if it fell from the outer edge). If you had no atmosphere, a clear shot, and the "ideal" penny cannon to launch it, you could hypothetically reach escape velocity with only a quarter stick of dynamite.

Incidental bursts of gas, or even outright exploding objects in space are not going to launch a bunch of stuff into much deeper orbit. There's a constant downward pull, and gas and dust creating drag and downward acceleration the closer in you get, and just vast, incomprehensible distances to travel under the influences of gravity. Getting things to go faster than 25,000mph, or reaching escape velocity, without vaporizing the thing you're trying to make go fast, requires as big a continuous explosion as you can make over as long a time period as possible.

I love that AI can whip up an xkcd style "What-If?" type scenario for these questions.