Explanation:
These three ancient, large impact craters lie on the
north
eastern shores of Mare Nubium, the
lunar Sea of Clouds.
Along the top of
the
stark mosaic (left to right) are
the
namesakes of Ptolemaeus, Alphonsus and Arzachel.
The picture offers a remarkably detailed view of the
well-studied
region with shadows emphasizing the large crater central peaks
and slumping walls.
Careful examination also reveals the 110 kilometer long
Straight
Wall, a fault 200-300 meters high, and the intriguing
Davy crater chain.
Overall, the striking moonscape is similar to the final images
recorded by the
Ranger 9 spacecraft, before
it crashed into the 108 kilometer wide crater Alphonsus
in March of 1965.