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Re:Starlink lost 40 satellites to a geomagnetic storm by barbecue_sauce on Tuesday February 08, 2022 @11:00PM (#30268638)
When people say something will "burn up on reentry", a phrase that I've heard almost all of my life but never really given much thought too, how burnt are we talking? Surely it doesn't just completely atomize?
Re:Starlink lost 40 satellites to a geomagnetic storm by mlindner on Wednesday February 09, 2022 @12:51AM (#30269391)
Here's a video of a satellite (a very large one) reentering: https://www.youtube.com/watch?v=OhBw5yaR_SU

And here's a timelapse in a hypersonic plasma test chamber: https://www.youtube.com/watch?v=q_AcG4ZQItg

(Keep in mind the pieces that come off are still going to keep being heated even after they seperate.)

It largely does atomize yes, depending on the material. Which is why they're designed out of materials that will do this.

Re:Starlink lost 40 satellites to a geomagnetic storm by Lev1a on Tuesday February 08, 2022 @11:22PM (#30268778)
I don't know specifically but as a layman I'd imagine the satellite breaking up into smaller and smaller pieces due to the rapid heating and the "wind resistance"(?) from making contact with the atmosphere at high speeds.

I'd also imagine that at some point in this breaking-up-process the pieces are small enough to sublimate from the extreme heat, i.e. "burning up".

Re:Starlink lost 40 satellites to a geomagnetic storm by sennight on Wednesday February 09, 2022 @12:26AM (#30269205)
You know how racecars spectacularly fly to pieces when they crash? That is by design - as it rapidly sheds energy. Same thing applies to things that "burn up on reentry", so long as you prevent the thing from coming down as one solid lump of glowing hot metal - the surface area to mass ratio renders the fragments harmless.

I wonder if anyone has ever tested the whole thing about field mice surviving a drop from any height due to their low terminal velocity... those bat bombs in WWII don't count.

Re:Starlink lost 40 satellites to a geomagnetic storm by MPSimmons on Wednesday February 09, 2022 @12:11AM (#30269107)
Do you remember, back when SpaceX used aluminum grid fins, when you'd see a Stage 1 re-entering, and you could watch the grid fins erode away in realtime video?

Think of that, but for, well, everything.

Re:Starlink lost 40 satellites to a geomagnetic storm by bipvanwinkle on Tuesday February 08, 2022 @11:16PM (#30268740)
I’d love to know more about this too.