NASA's Mars Global Surveyor shows a small impact crater with a 'butterfly' ejecta pattern. The butterfly pattern results from an oblique impact.

22 June 2005
This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a small impact crater with a "butterfly" ejecta pattern. The butterfly pattern results from an oblique impact. Not all oblique impacts result in an elliptical crater, but they can result in a non-radial pattern of ejecta distribution. The two-toned nature of the ejecta -- with dark material near the crater and brighter material further away -- might indicate the nature of subsurface materials. Below the surface, there may be a layer of lighter-toned material, underlain by a layer of darker material. The impact throws these materials out in a pattern that reflects the nature of the underlying layers.

Location near: 3.7°N, 348.2°W
Image width: ~3 km (~1.9 mi)
Illumination from: lower left
Season: Northern Autumn

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