December 4, 2011. 22:00-22:30UT. 200mm SCT f/10. 333x
Object Name: Eratosthenes Crater
Object Type: Lunar Crater
Location: Naxxar, Malta
Date: December 4, 2011
Media: Graphite pencil, white paper, blending stumps, erasor, GIMP.
Telescope: 8 inch f/ 10 SCT Dobsonian and 10mm eyepiece using binoviewer
Date: 12-04-2011 22:00-22:30 UT
Charles Galdies – http://znith-observatory.blogspot.com
Eratosthenes is a very dramatic and beautiful deep crater with a well-defined circular rim, terraced inner walls, a central mountain peak, but lacking its own ray system. The sketch, which is my third and best sketch of Eratosthenes so far, was done at relatively low sun-angles to bring out the shadow cast by the crater and adjacent western terminus of the Montes Apenninus mountain range. What makes this formation interesting to sketch is its linkage with the Apennine mountain chain.
In my sketch I tried to bring out the following features:
Rays from the prominent crater Copernicus to the south-west
Fine detail of the western terminus of the Montes Apenninus mountain range.
Numerous craterlets which typify the region around Eratosthenes
Internal wall terracing
Way back in 1924 Pickering noted dark patches in the crater that varied in a regular manner with time. He attributed these mobile patches to around 36 different flowering plants. Check out this old document http://articles.adsabs.harvard.edu//full/1925PA…..33..629M/0000630.000.html written by one of his associates about this.