Sol 4173, October 20, 2015. The season at Endeavour Crater is slipping toward winter, and rover drivers are looking for bits of ground that tip Opportunity northward even slightly to enhance its solar power. At the same time, scientists are inventorying outcrops on the floor of Marathon Valley to identfy patches of rock that may contain clay minerals.
At right is a false-color Pancam image (by Holger Isenberg) focusing on the “work volume” where the rover’s arm can place the APXS instrument to study the rock. (Click image to enlarge.)