Sol 4323, March 23, 2016. Opportunity is exploring Marathon Valley because orbital spectrometry found exposures of water-altered clay minerals in the valley. But with the ground proving too loose to allow Opportunity to reach its intended outcrop target at Pvt. Joseph Whitehouse, mission scientists are now planning to search higher, driving back up the valley to where the ground should be more trafficable.
A poster talk (PDF) by Larry Crumpler (New Mexico Museum of Natural History & Science) Tuesday evening at the 47th Lunar and Planetary Science Conference provides a local geological map of the valley floor and the flanking knolls and ridges, plus a discussion of its geological history.
To keep solar power strong, the rover will stay on north-tipping slopes, which are on the left side of the Navcam composite above. Click to enlarge.
Opportunity raw images, its latest mission status, a location map. and atmospheric opacity, known as tau.