Examples Luna and Apollo

The soft-lander Luna 16, which returned samples of lunar soil to Earth, was placed first into a 110 km circular lunar orbit. It was then put into a 15 X 106 km orbit, with landing approach to be made from perilune. The vehicle simply killed its 1.7 km s~1 orbital speed and then fell vertically. The free-fall was monitored by a radar altimeter, and arrested at an altitude of 600 m (~200 m s~1) by another burn. Again, note the low altitude of these manoeuvres to maximize propulsive efficiency.

The more massive Apollo vehicles had a lower thrust-to-weight ratio, and followed a more complex, shallow approach (which can be practised in the early 'Lunar Lander' arcade game).

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