L12 - Proclus
For a very wide range of impact angles, the material ejected when a crater forms will spread out uniformly in all direction, as seen in craters like Tycho or Copernicus. However, when the impact angle is very low, the ejecta pattern is more directional. Between Mare Tranquillitatis and Mare Crisium lies the crater Proclus, the best example of such an impact.
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Images © Doug Anderson
This image was taken on 11-Jan-2006 through a 203mm Celestron C-8 Schmidt-Cassegrain reflector with a Canon Digital Rebel XT (350D) camera using eyepiece projection through a 15mm eyepiece.