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Comment by zackbloom | Hacker News Reader

Think how big the Earth is. How hard it would be to find a Xerox machine in the Amazon or the middle of the Atlantic if someone stuck it there. Space is much, much, bigger.

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> How hard it would be to find a Xerox machine in the Amazon or the middle of the Atlantic if someone stuck it there.

Part of the problem, though, is that said Xerox machine is traveling at 17,000 miles per hour.

We've already had a collision (https://en.wikipedia.org/wiki/2009_satellite_collision) between two of the ~3-4k satellites in orbit. SpaceX's constellation is planned to be double that number.

That single collision turned two satellites into two thousand high-velocity projectiles, too.

> That single collision turned two satellites into two thousand high-velocity projectiles, too.

Just to add to that point: https://en.wikipedia.org/wiki/Envisat#Space_safety

A single 10kg. chunk of debris could result in over 8 tonnes of additional debris, triggering a rather nasty chain reaction.

I'm no stranger to the vast physical space at play here (amateur astronomer, here). I'm aware there is a LOT of room for this stuff to move around, but there is still a threshold, however high, to where the amount of debris would become dangerously numerous.

And you think that we can only fit <10k objects in an area larger than the surface of the earth?

At any one time there are usually <10k airplanes in the sky,and they still hit each other sometimes despite going 23x slower than satellites

To be fair, a lot of that is because of the fact that planes follow paths that are designed to keep collisions from happening, but aren't always adhered to.

The vast majority of those collisions occur in areas where planes are forced to congregate (around airports, etc).

Isn't there high traffic where polar intersect? See: https://en.wikipedia.org/wiki/2009_satellite_collision.

<10K isn't the problem. It's when that 10K becomes much, much larger because of an unforeseen collision with an unrelated spacecraft/piece of space junk. It only takes one big collision to utterly litter that particular orbit, and thousands of slightly different orbits caused by the new trajectories of the various bits of the original spacecraft.

So whats your solution? Never put a bunch of satellites in space?

He's not necessarily saying he know's a solution, just that such a problem should be considered. Satellites do collide - https://en.wikipedia.org/wiki/2009_satellite_collision

The idea of satellite collisions and space junk is an actual concern https://en.wikipedia.org/wiki/Kessler_syndrome .

Sure a few washing machines in space isn't a big concern. Now imagine a few collide, hundreds of bits and bolts flying around earth, at unknown trajetories, at thousands of miles per hour.

There are a variety of potential mitigations. Legal requirements that satellites deorbit or park in a safe orbit before going dark, technology like https://en.wikipedia.org/wiki/E.Deorbit to capture and deorbit large chunks, better tracking of orbital debris, etc.

There has been a collision between an Iridium satellite and another one before. It's a valid concern.

If they're travelling 7 km a second, maybe??

Now imagine that Xerox machine is constantly moving at 17,000 mph. How interested would you be in figuring out where its going?

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