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WW

HEADERS_END

The speed you must go to be in orbit.

Slightly misleading, as your orbital velocity depends on your orbital height:

the higher your orbit, the slower you go.

It's relatively easy to compute orbital velocity for an Earth grazing orbit,

and that's intimately related to the calculation of the distance to the horizon.

Escape velocity is larger by a factor of EQN:\sqrt{2}, which is interesting.