Hollows exposed in a small Mercury crater wall

Hollows exposed in a small Mercury crater wall
Hollows exposed in a small Mercury crater wall This is the first set of images acquired during MESSENGER's low-altitude imaging campaign, a key part of its second extended mission. Low-altitude imaging allows higher-resolution views; this crater is only 15 kilometers in diameter, and the image has a resolution of 16 meters per pixel. Near the crater rim are some hollows, which appear to all be forming at the same elevation within the crater, possibly as a result of the exposure of a layer that contains material that can sublimate from a solid to a gas. NASA / JHUAPL / CIW