Solar System Exploration
4/24/2014: MESSENGER space-craft in orbit around Mercury obtained this image of the peak-ring basin Scarlatti (center) on 3/30/2014. Scarlatti has a ring of peaks at its center, typical in many respects, although in the NE sec-tion, it transitions to a large (approx.19 mi) pit surrounded by high-reflectance material. Past explosive volcanic activity may have created this pit. Tom Chao
"Platey" material on the floor of Kasei Valles This image covers an area about 2600 by 5000 meters in size. The valley is at upper left; its floor is covered with platey material. The platey material stops at the edge of a plateau or mensa at lower right, indicating that the platey material flooded the valley after it and the plateau formed.
Can you tell which is Earth and which is Mars? On the left, images from the Red Planet as captured by the Opportunity rover and the Mars Reconnaissance Orbiter. On the right, locations of roughly the same scale in and around Canyonlands National Park, Utah. Details at the link.