A ‘Blue Tongue’ on Mercury (NASA, MESSENGER, 05/16/11) (by NASA’s Marshall Space Flight Center)
<i>Via Flickr:</i>
This high-resolution color image shows a 14-kilometer diameter crater that is relatively young, as indicated by the bright rays that cross the neighboring features. A dark "tongue" of impact melt, which has a bluer color than the nearby surface, appears to have flowed out of the crater.
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington