Lyell (Martian crater)

Lyell Crater is an impact crater in the Mare Australe quadrangle of Mars, located at 70.1°S latitude and 15.6°W longitude. It is 121.0  km in diameter. Its name refers to British geologist Charles Lyell.[1]

Lyell Crater

Location of Lyell Crater.
Planet	Mars
Region	Mare Australe quadrangle
Coordinates	70.1°S 15.6°W / -70.1; -15.6
Diameter	121 km
Eponym	Charles Lyell

This picture was taken in the spring season on Mars when the temperature was rising. During the winter, much frost accumulates. When the temperature goes up in the spring, the frost disappears in the thin Martian atmosphere and leaves behind the dark ground. The surface appears covered with dark spots when this defrosting process is occurring.[2] The dark spots can be seen in some of the pictures below. Many gullies are present in Lyell Crater.

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  Lyell (Martian crater), as seen by CTX camera (on Mars Reconnaissance Orbiter).
• 
  Gullies in Lyell crater, as seen by CTX camera (on Mars Reconnaissance Orbiter). Note: this is an enlargement of the previous image of Lyell crater.
• 
  Defrosting taking place in Lyell crater, as seen by CTX camera (on Mars Reconnaissance Orbiter). Dark areas are where frost has disappeared thereby showing dark ground. Note: this is an enlargement of a previous image of Lyell crater.