What is "lyell"

Lyell is a lunar crater that lies along the eastern edge of the Mare Tranquillitatis, at the northern arm of the bay designated Sinus Concordiae. To the north along the edge of the lunar mare is the crater Franz. The region of terrain to the east of Lyell is named Palus Somni.

The outer rim of this crater is an irregular series of ridges in a roughly circular formation. There are multiple gaps through this rim, connected the interior to the mare in the west. The wall is at its thickest along the eastern side of the crater.

The interior floor has been resurfaced by lava, leaving a level, featureless surface that has no markings or impacts of note. The central region of the inner floor has a relatively low albedo compared to the surrounding terrain, giving it a dark appearance that matches the nearby mare.

Lyell is a surname of Scotland traced to Radulphus de Insula, 11th-century Lord of Duchal. "De insula" was subsequently translated into the Old French "de l'isle" and developed into a number of variants ([de] Lyell; [de] Lisle; [de] Lyle; see below). John Lyell in 1706 emigrated to Virginia and is the progenitor of the American Lyells.

Lyell may refer to:

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 131.0 km in diameter and was named after Charles Lyell, and the name was approved in 1973 by the International Astronomical Union (IAU) Working Group for Planetary System Nomenclature (WGPSN).

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. The dark spots can be seen in some of the pictures below.

Many gullies are present in Lyell Crater.