r/Damnthatsinteresting Mar 06 '25

GIF RemoveDEBRIS satellite harpoons space junk in a plan to clean Earth's orbit

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u/francis2559 Mar 06 '25

No, Starlink is in low earth orbit and they need to launch so many over time because they crash relatively quick. They're low enough to experience significant atmospheric drag.

It's his cheap launch capacity that actually let him do this (low orbit, low latency, big cloud). It's not a novel idea, it just would have been prohibitively expensive for old space.

The lingering stuff is the stuff that's much further out.

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u/Nami_Pilot Mar 06 '25

You're right, the latency would be too high if they were in a higher orbit.

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u/CurrentResinTent Mar 06 '25 edited Mar 06 '25

I’m not so sure that is true about latency. It’s my understanding that RF travels at near the speed of light, but I am open to learning more here. With that said it is definitely beneficial to reliable communication for the transceivers to be closer to the surface of the earth.

ETA: For those that decided in replies that I was wrong without the science to back it up, my understanding was exactly correct, but my knowledge of how fucking far away a typical satellite orbits was lacking.

My latency estimates below are purely based off of the RF transmission, neglecting real world bottlenecks of weather conditions, server latency, comms congestion, etc.

RF does travel at the speed of light, which means starlink’s altitude of roughly 550km would result in a round trip latency of 37ms.

Geosynchronous orbiting communications satellites (from my quick internet search) orbit at an estimated altitude of 35,786km, which would result in a round trip latency of 239ms. That’s a pretty big difference.

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u/EV4gamer Mar 06 '25

the speed of light is slow. Also, if youre further away you simply need more power for the same signal to noise, or speed in this case.

This effect scales by distance squared, so being as close as possible is a huge advantage.

The only advantage of being further away is that youre in a slower orbit, and you see more of the earth at once