Mars Exploration Rovers Update - August 11, 2006

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

SPIRIT UPDATE: Spirit Survives Second Winter Solstice on Mars - sol
922-928, August 11, 2006:

Spirit has now survived the rover’s second Martian winter solstice –
the shortest day of the year with the least amount of sunlight and
solar
energy. The solstice arrived on the rover’s 923rd Martian day, or sol
(Aug. 8, 2006). Spirit is healthy and continues to make progress on its
winter science campaign.

Having completed the “McMurdo mega-panorama,” Spirit is currently
filling cracks between frames by acquiring touch-up images (dubbed
“grout” by engineers). The rover is also spending this week and next
making a series of atmospheric observations at the same time each day.

Spirit continues to collect about 280 watt-hours of electrical power
each sol from the rover’s solar array (a hundred watt-hours is the
amount of electricity needed to light one 100-watt bulb for one hour).

Sol-by-sol summaries:

Sol 922 (Aug. 7, 2006): Spirit measured atmospheric dust opacity (known
as a tau measurement) with the panoramic camera, surveyed the sky and
ground with the miniature thermal emission spectrometer, and acquired
fill-in images with the panoramic camera for column 24A (a single
frame)
of the McMurdo pan.

Sol 923: Spirit took a tau measurement with the panoramic camera,
surveyed the sky and ground with the miniature thermal emission
spectrometer, and acquired morning fill-in images for the McMurdo pan
with the panoramic camera.

Sol 924: Spirit took a tau measurement with the panoramic camera,
surveyed the sky and ground with the miniature thermal emission
spectrometer, and acquired panoramic camera images of the “El Dorado”
dune field (a two-by-one mosaic). The rover acquired images of fine
ripples with the hazard avoidance cameras and a rearward-looking view
with the left eye of the right rear hazard avoidance camera. Spirit
also
acquired morning fill-in images for the McMurdo pan.

Sol 925: Spirit took a tau measurement with the panoramic camera,
surveyed the sky and ground with the miniature thermal emission
spectrometer, and acquired morning fill-in images for the McMurdo pan
with the panoramic camera. Spirit also took a sunset tau measurement,
an
observation during which the rover evaluates atmospheric opacity at
sunset to estimate dust height.

Sol 926: Plans called for Spirit to take a tau measurement with the
panoramic camera, survey the sky and ground with the miniature thermal
emission spectrometer, and acquire morning fill-in images for the
McMurdo pan.

Sol 927: Plans called for Spirit to take a tau measurement with the
panoramic camera, survey the sky and ground with the miniature thermal
emission spectrometer, and acquire compositional data on a
rock-and-soil
target known as “Halley Brunt Offset 2” using the alpha particle X-ray
spectrometer. Plans also called for Spirit to complete a morning sky
survey using the panoramic camera.

Sol 928 (Aug. 13, 2006): Plans called for Spirit to take a tau
measurement with the panoramic camera, survey the sky and ground with
the miniature thermal emission spectrometer, and acquire morning
fill-in
images for the McMurdo pan.

Odometry:

As of sol 924 (Aug. 9, 2006), Spirit’s total odometry remained at
6,876.18 meters (4.27 miles).


OPPORTUNITY UPDATE: Opportunity Recovers from Brief Operational Anomaly

  • sol 900-906, August 11, 2006:

While Opportunity was collecting images with the panoramic camera on
the
rover’s 902nd Martian day, or sol (Aug. 7, 2006), a spacecraft anomaly
at 11:19 a.m. local solar time caused the rover’s fault protection
software to interrupt operations, place the rover in a safe state, and
reboot the flight software. Upon waking up after the reset, Opportunity
flagged the positions of the high-gain antenna and pancam mast assembly
as unknown. Opportunity then remained in automode (meaning the rover
did
not attempt to execute a master sequence of activities for the day).

The rover’s handlers transmitted instructions to Opportunity to
re-establish the position of the high-gain antenna on sol 903 (Aug. 8,
2006) and the position of the pancam mast assembly on sol 904 (Aug. 9,
2006). Sols 903 and 904 were primarily dedicated to retrieving
diagnostic information. On sol 904, Opportunity successfully reacquired
the sequence of panoramic camera images that had been terminated by the
fault and collected scientific data. As of sol 905 (Aug. 10, 2006),
Opportunity was completely restored to normal operations. Opportunity
remains healthy and engineers have not found a credible explanation for
what caused the anomaly.

Before the fault, Opportunity had been working on a campaign of science
observations of the area around “Beagle Crater,” including an analysis
of laminated ripples using instruments on the rover’s robotic arm.
Opportunity has resumed work on those observations.

Sol-by-sol summaries:

Sol 900 (Aug. 5, 2006): Opportunity made tau observations (measurements
of dust opacity in the atmosphere) using the panoramic camera and
completed two image mosaics of Beagle Crater with the panorama camera:
a
four-by-four mosaic known as “Beagle Pan B” and a two-by-four mosaic
known as “Beagle Pan D.” Opportunity acquired images of a target known
as “Fernandina” using all 13 filters of the panoramic camera and made
observations of a target known as “Darwin” with the miniature thermal
emission spectrometer. The rover acquired morning panoramic camera
images of targets “Camarhynchus” and “Cactospiza” and a portion of the
sky. Opportunity checked for drift (changes with time) in the miniature
thermal emission spectrometer and surveyed the sky and ground with the
same instrument.

Sol 901: Opportunity made tau observations using the panoramic camera
and completed two image mosaics of Beagle Crater with the panorama
camera: a four-by-four mosaic called “Beagle Pan A” and a four-by-four
mosaic called “Beagle Pan C.” Opportunity acquired images of a target
known as “Floreana” using all 13 filters of the panoramic camera. The
rover acquired miniature thermal emission spectrometer data from
Camarhynchus and a target called “Geospiza.” Opportunity acquired
panoramic images of a target known as “Platyspiza.”

Sol 902: Opportunity made tau observations with the panoramic camera.
At
11:19 a.m. local solar time, a spacecraft fault put the rover in a safe
state.

Sol 903: Opportunity ran engineering sequences to recover from the
previous day’s fault responses and retrieve diagnostic data.

Sol 904: Opportunity acquired stereo images with the navigation camera
without activating the pancam mast assembly and ran engineering
sequences to complete the rover’s recovery from the fault that occurred
on sol 902. Opportunity took images of the calibration target for the
panoramic camera and re-acquired “Beagle Part 5,” the sequence of
images
that was terminated by the fault on sol 902.

Sol 905: Opportunity made tau observations using the panoramic camera,
acquired a two-by-one mosaic of Darwin with the panoramic camera, and
acquired images of Geospiza using all 13 filters of the panoramic
camera. The rover scanned for clouds using the navigation camera’s wide
field of view. Opportunity also checked for drift in the miniature
thermal emission spectrometer and surveyed the sky and ground with the
same instrument.

Sol 906 (Aug. 11, 2006): Plans called for Opportunity to take tau
measurements with the panoramic camera, monitor dust on the pancam mast
assembly using the miniature thermal emission spectrometer, survey the
ground and sky at various elevations using the miniature thermal
emission spectrometer, and collect reference data from the calibration
target for the thermal emission spectrometer. During this procedure,
the
rover was to check for drift (changes over time) in measurements from
the instrument.

Odometry:

As of sol 897 (Aug. 2, 2006), Opportunity’s total odometry was 8,687.56
meters (5.4 miles).