Archimedes (crater)

From Wikipedia, the free encyclopedia

Crater characteristics
Archimedes from Apollo 15. NASA photo.
Coordinates	29.7° N, 4.0° W
Diameter	83 km
Depth	2.1 km
Colongitude	4° at sunrise
Eponym	Archimedes

Archimedes is a large lunar impact crater on the eastern edges of the Mare Imbrium. To the south of the crater extends the Montes Archimedes mountainous region. On the southeastern rim is the Palus Putredinis flooded plain, containing a system of rilles named the Rimae Archimedes that extend over 150 kilometers. North-northwest of Archimedes stand the Montes Spitzbergen, a string of peaks in the Mare Imbrium.

East of Archimedes is the Autolycus crater, and the stretch of lunar surface between these two formations was the crash-landing site of the Luna 2 landing craft. This was the first robotic craft to reach the surface of the moon, landing September 13, 1959.

To the northwest is the prominent Aristillus crater. The lava plain between Archimedes, Aristillus, and Autolycus forms the Sinus Lunicus bay of Mare Imbrium. A wrinkle ridge leads away from Archimedes toward the north-northwest, crossing this maria.

The diameter of Archimedes is the largest of any crater on the Mare Imbrium. The rim has a significant outer rampart brightened with ejecta and the upper portion of a terraced inner wall, but lacks the ray system associated with younger craters. A triangular promontory extends 30 kilometers from the southeast of the rim.

The interior of the crater lacks a central peak, and is flooded with maria. It is devoid of significant raised features, although there are a few tiny meteor craters near the rim. Scattered wisps of bright ray material lie across the floor, most likely deposited by the impact that created Autolycus crater.

[edit] Illustrations

The Archimedes crater on the Moon. Image courtesy of NOT and SO: M. Gålfalk, G. Olofsson, and H.-G. Florén.

Detail map of Mare Imbrium's features. Archimedes is the feature marked "G".

[edit] Satellite craters

By convention these features are identified on lunar maps by placing the letter on the side of the crater mid-point that is closest to Archimedes crater.

The following craters have been renamed by the IAU.

• Archimedes A - See Bancroft crater.
• Archimedes F - See MacMillan crater.
• Archimedes K - See Spurr crater.

[edit] References

• See the reference table for the general listing of literature and web sites that were used in the compilation of this page.