horizonPitch

The pitch that puts the horizon on the middle of the frame from height.

Below the horizon, and by more than people expect: from 2 m up on an Earth-sized body the horizon is 0.045° down, and from 400 km it is 19.79°. A scrub that held pitch at zero from orbit to the ground would therefore spend the top of its travel aimed at empty sky — the body is below you up there — so the descent control tracks this instead. acos(r / (r + h)) is the exact dip to the tangent point; the small-angle √(2h/r) reads 20.30° at the same height, 2.6% high and growing with h.

radiusnumber

Undocumented

heightnumber

Undocumented