From Newsgroup: sci.space.news


OPPORTUNITY UPDATE:

sols 4378-4384, May 17, 2016-May 24, 2016: Investigating the Soil Exposed
with the Rover Wheel

Opportunity is exploring 'Marathon Valley' on the rim of Endeavour crater, inspecting specific outcrops for evidence of clay minerals.

Previously, the rover used the left-front wheel to scuff a red vein feature
to break up and expose its compositional material for further investigation.
On Sol 4379 (May 18, 2016), Opportunity bumped 6 feet (1.75 meters) back towards the scuff to set up for an in-situ (contact) investigation of
the scuffed material. The rover also collected some targeted Panoramic
Camera (Pancam) 13-filter images and a Navigation Camera (Navcam) panorama.

On Sol 4381 (May 21, 2016), Opportunity began the contact investigation
using the robotic arm to collect a Microscopic Imager (MI) mosaic of the
scuff and then place the Alpha Particle X-ray Spectrometer (APXS) on the
same. On the next sol, the rover offset the APXS on the scuff by about
1 centimeter and performed another integration. Opportunity continued
on the next sol with yet another APXS offset placement, more MI mosaics
and some more targeted Pancam 13-filter imaging.

As of Sol 4384 (May 24, 2016), the solar array energy production is 636 watt-hours with an atmospheric opacity (Tau) of 0.605 and a solar array
dust factor of 0.756.

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

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sols 4385-4391, May 25, 2016-May 31, 2016: Study of 'Wheel Scuff' Continues

Opportunity is exploring 'Marathon Valley' on the rim of Endeavour crater, investigating outcrops for evidence of clay minerals. The rover is continuing to examine a previously trenched (scuffed) surface.

On Sol 4385 (May 25, 2016), Opportunity collected some more targeted Panoramic Camera (Pancam) 13-filter images and continued with an Alpha Particle
X-ray Spectrometer (APXS) integration on the surface target. Then, on
Sol 4386 (May 26, 2016), Opportunity bumped ever so slightly (about 1
cm) in order to reach a particular yellow pebble in the trenched area.
The rover collected more targeted 13-filter Pancam images. And then on
Sol 4389 (May 29, 2016), Opportunity used the robotic arm (IDD) to collect
a Microscopic Imager (MI) mosaic of the yellow pebble and to position
the APXS just above the pebble (since it was too small to make a contact placement). More targeted color Pancam images have been collected over
the subsequent sols.

As of Sol 4391 (May 31, 2016), the solar array energy production is 643 watt-hours with an atmospheric opacity (Tau) of 0.566 and a solar array
dust factor of 0.738.

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


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ls 4392-4398, June 01, 2016-June 07, 2016: Examining Pebbles Exposed
by 'Wheel Scuff'

Opportunity is exploring 'Marathon Valley' on the rim of Endeavour crater, investigating outcrops for evidence of clay minerals.

The rover is continuing to examine a previously trenched (scuffed) surface where distinct pebbles have become a focus of interest for the science
team. On Sol 4392 (June 1, 2016), Opportunity continued the investigation
of a 'yellow' pebble with an offset positioning of the Alpha Particle
X-ray Spectrometer (APXS). This pebble has exhibited an elevated sulfate composition. Offset APXS measurements allow the 'teasing out' of the elements associated with the pebble versus those in the background (soil).

Over the next two sols, the APXS was allowed to integrate while the rover collected several multi-color panoramic images of the surroundings. On
Sol 4395 (June 4, 2016), the rover performed another offset positioning
of the APXS followed with a multi-hour integration. On the next sol, a Microscopic Imager (MI) mosaic was collected using the robotic arm and
the APXS was offset again for yet another integration.

On Sol 4398 (June 7, 2016), with the work complete on the 'yellow' pebble,
the rover bumped about 4 inches (10 centimeters) to another pebble of
interest for in-situ (contact) investigation over the coming sols.

As of Sol 4398 (June 7, 2016), the solar array energy production is 637 watt-hours with an atmospheric opacity (Tau) of 0.597 and a solar array
dust factor of 0.735.

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

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sols 4399-4405, June 08, 2016-June 14, 2016: Opportunity Wraps up Work
on 'Wheel Scuff'

Opportunity is exploring 'Marathon Valley' on the rim of Endeavour crater, investigating outcrops for evidence of clay minerals.

The rover is close to completing its investigations within Marathon Valley.
On Sol 4400 (June 9, 2016), Opportunity continued with the in-situ (contact) investigation of the area that was scuffed by the rover wheel. The rover collected a Microscopic Imager (MI) mosaic of the 'red pebble' target
and then placed the Alpha Particle X-ray Spectrometer (APXS) on the same
for a multi-hour integration.

On Sols 4402 and 4403 (June 11 and 12), Opportunity performed a 2-sol
plan each with MI imagery and further offset APXS placements to map out
the elemental constituents of the target. On Sol 4404 (June 13, 2016),
the rover bumped back, collected 13-filter images of the work area, then bumped further back, totaling 4.6 feet (1.4 meters).

With the work complete at this site, Opportunity drove away on Sol 4405
(June 14, 2016), with a 62-feet (19-meter) drive heading towards the center
of the area where a clay mineral signature has been observed from orbit.

As of Sol 4405 (June 14, 2016), the solar array energy production is 658 watt-hours with an atmospheric opacity (Tau) of 0.645 and a solar array
dust factor of 0.752.

Total odometry is 26.60 miles (42.81 kilometers), more than a marathon.

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