Explanation:
Why does this crater on Mercury look like a spider?
When the robotic
MESSENGER spacecraft
glided by the planet Mercury
last month, it was able to image portions of the Sun's closest planet that had never been seen before.
When imaging the center of Mercury's extremely large
Caloris Basin,
MESSENGER found a crater, pictured above, with a set of unusual
rays emanating out from its center.
A crater with such troughs has never been seen before anywhere in
our Solar System.
What isn't clear is the relation of the crater to the radial troughs.
Perhaps the crater created the
radial rays, or perhaps the two features appear only by a chance superposition --
the topic is sure to be one of future research.
MESSENGER is scheduled to fly past Mercury twice more before
firing its thrusters to
enter orbit in 2011.
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