From the April 2013 issue

How do mission designers know at what angle to land on an astronomical body such as the Moon, Mars, or Earth?

Matthew Schewe, Eden Prairie, Minnesota
By | Published: April 22, 2013 | Last updated on May 18, 2023

A planetary body’s atmosphere controls the angle during entry, descent, and landing from a combination of the gravitational force and atmospheric drag. Venus and Earth have thick atmospheres, so drag slows the entry capsule to the point where it falls straight down to the surface the last few miles.

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