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Comment by DuskStar | Hacker News Reader

The graveyard orbits are ~40,000km above the earth's surface - there's a LOT of space to avoid debris in.

The issue with space debris is with orbits in the 500-5,000km range. Lower than that and the debris will reenter quickly, higher and you start getting spread out enough to not matter as much.

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> The graveyard orbits are ~40,000km above the earth's surface

They're also in a ring in the plane of the equator. Easy to avoid.

I had no idea about this. How do they get it aligned with the equator? (I'm assuming when the stuff is in operation that it's not just around the equator)

No, geostationary satellites actually are in a plane around the equator. That’s the only way geostationary orbit works. Otherwise they’d be moving with respect to the surface.

So they already are aligned and just need to be moved to a higher orbit.

Geostationary satellites are in fact in a ring around the equator. No other orbit would keep them stationary in the sky.

Geosynchronous orbits are orbits at the same altitude, but not necessarily aligned with the equator. Most of what I know about orbital mechanics I learned from Kerbal Space Program, but given that it's very expensive to change orbital inclination, I would be shocked if geosynchronous satellites were returned to a flat inclination before being disposed of.

KSP is a very good approximation for most types of orbits we care about, including this case. Anything not involving N-body, like Lagrange points.

Geostationary satellites are launched from near the equator and then accelerated into a true eastward orbit when they're put into service (eastward because the earth rotates in an eastward direction and we want the satellite's orbit to synchronize with the earth's rotation). They could in principle be launched from far away from the equator e.g. Florida but that would require a ridiculous amount of fuel to get them into an equatorial orbit. Once they go out of service, their onboard thrusters fire (accelerating the craft in a mostly easterly direction -- not "up"!) which has the effect of raising their orbital height to a graveyard orbit.

Too late to edit the above, but I need to make a major correction: US geostationary satellites are indeed launched from Florida, followed by a fuel-expensive plane change to get them into the equatorial plane. Other countries launch them from land they own or control closer to the equator.

Well, they start getting spread out — except when you have everything together for that one special geosynchronous orbit. That's a bit of a problem too.

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