[meteorite-list] Mars Exploration Rovers Update: June 18-24, 2009

[Ron Baalke]

http://marsrovers.jpl.nasa.gov/mission/status.html

SPIRIT UPDATE:  Studying Troy* /- sols 1941-1947, June 18-24, 2009:

Spirit is continuing her ambitious remote sensing and in-situ (contact)
science observations at the location called "Troy" on the west side of
Home Plate.

Using the rover robotic arm (instrument deployment device, IDD), the
rover has been exploring a set of surface targets that hold clues to the
past geologic history at this location.

On Sol 1941 (June 18, 2009), a Microscopic Imager (MI) stack of images
was collected on target Penina3, then the Alpha Particle X-ray
Spectrometer (APXS) was placed for an overnight integration. On the next
sol, the Moessbauer Spectrometer (MB) was placed on a different target
for a multi-sol integration. The next few sols included some late-day
activities where the rover imaged the Earth and Venus in the night sky.

On Sols 1945 and 1946 (June 22 and 23, 2009), Spirit investigated
another set of surface targets, again with MI stacks and APXS overnight
integrations. On Sol 1946 (June 23, 2009), another solar array dust
cleaning event occurred, increasing the available energy each sol even
more.

At JPL, a special test form has been installed for ground testing with
the surface system testbed (SSTB) rover to guide the eventual extraction
activities on Mars for Spirit. The materials for the soil simulant to be
used in the test form have been delivered and are in the process of
being formulated and mixed. As of Sol 1947 (June 24, 2009), solar array
energy production increased to 945 watt-hours with atmospheric opacity
(tau) of 0.480 and an improved dust factor of 0.834. Total odometry
remains at 7,729.93 meters (4.80 miles).

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OPPORTUNITY UPDATE:  Moving to Outcrop* /- sols 1920-1926, 
June 18-24, 2009:

Opportunity has been moving toward a candidate patch of rock outcrop in
preparation for a rest of the mobility system over the coming holiday.
There continues to be concern with the elevated motor currents seen in
the right front wheel.

On Sol 1920 (June 18, 2009), Opportunity drove backwards about 63 meters
(207 feet) south. The right front wheel currents were elevated but were
not divergently increasing. After a few sols, Opportunity drove another
7 meters (23 feet) to a nearby outcrop.

Robotic arm activities on surface targets with the microscopic image
(MI) and the alpha particle X-ray spectrometer (APXS) were performed on
Sols 1924 and 1925 (June 22 and 23, 2009).

Further drives are planned to reach a large region of rock outcrop.
Also, the week saw further implementation of the miniature thermal
emission spectrometer (Mini-TES) mirror dust mitigation. The Mini-TES
shroud is left open overnight to see if the environment will clean the
elevation mirror.

As of Sol 1924 (June 22, 2009), the solar array energy production was
450 watt-hours with an atmospheric opacity (tau) of 0.480 and a dust
factor of 0.530, indicating that 53 percent of sunlight hitting the
solar array penetrates the layer of accumulated dust on the array. As of
Sol 1926 (June 24, 2009), Opportunity's total odometry remains at
16,639.71 meters (10.3 miles)