Pasadena CA (JPL) May 23, 2016 Opportunity is exploring 'Marathon Valley' on the rim of Endeavour crater, searching specific outcrops for evidence of clay minerals.

The rover is currently conducting an in-situ (contact) science investigation on an outcrop target, called 'Pierre Pinaut.'

The rover has also been collecting a beautiful full-color panorama of the surrounding location.

On Sol 4372 (May 11, 2016), Opportunity collected a Microscopic Imager (MI) mosaic of the target previously ground by the Rock Abrasion Tool (RAT).

This was followed by the placement of the Alpha Particle X-ray Spectrometer (APXS) on the same.

On the next sol, the RAT brush was used to clean the ground target of tailings and another MI mosaic was taken with another APXS placement.

Following on the next sol, the APXS was offset just a half inch (1.25 centimeters) for another elemental integration.

With the contact work complete, on Sol 4375 (May 14, 2016), Opportunity backed away and collected some Panoramic Camera (Pancam) color imagery of the target.

On Sol 4377 (May 16, 2016), the rover used the left-front wheel to scuff a red vein feature to break up and expose its compositional material for further investigation.

As of Sol 4377 (May 16, 2016), the solar array energy production is 672 watt-hours with an atmospheric opacity (Tau) of 0.542 and a solar array dust factor of 0.770.

Total odometry is 26.59 miles (42.79 kilometers), more than a marathon.