Planet Mars | Diameter 105 km | |
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Eponym Ernst Hartwig, a German astronomer (1851-1923) | ||
Hartwig Crater is a crater in the Argyre quadrangle of Mars, located at 39° south latitude and 16° west longitude. It is 105 km in diameter and was named after Ernst Hartwig, a German astronomer (1851–1923).
Impact craters generally have a rim with ejecta around them, in contrast volcanic craters usually do not have a rim or ejecta deposits. As craters get larger (greater than 10 km in diameter) they usually have a central peak. The peak is caused by a rebound of the crater floor following the impact. If one measures the diameter of a crater, the original depth can be estimated with various ratios. Because of this relationship, researchers have found that many Martian craters contain a great deal of material; much of it is believed to be ice deposited when the climate was different.