[meteorite-list] Mars Exploration Rovers Update - August 4, 2006

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Fri Aug 4 12:33:14 2006
Message-ID: <200608041618.JAA00844_at_zagami.jpl.nasa.gov>

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

SPIRIT UPDATE: Spirit Completes Camera Check-Up, Puts Finishing Touches
on Panorama - sol 915-921, August 04, 2006:

Spirit has finished acquiring images for the "McMurdo panorama" and
began adding some finishing touches around the edges. The rover is
healthy and continues to make progress on its winter science campaign of
observations on Mars.

Plans called for Spirit to complete a winter check-up of all the rover's
cameras by calibrating the microscopic imager. To accomplish this
procedure, known as a photon transfer observation, Spirit acquired 20
pairs of images, each pair taken during a different exposure time.
Engineers used these images to form a baseline for estimating unwanted
electronic signals using a Poisson distribution.

The Poisson curve measures probability over a fixed time interval based
on a known average. Using this probability, engineers correlated the
signal measured by the camera with differences in signals acquired in
the image pairs to calculate the efficiency with which the camera's
imaging sensors convert photons from sunlight into electrical energy.
They used the same approach to characterize the electrical system's
ability to translate measurements of voltage into digital numbers.

Spirit is collecting 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 summary:

Sol 915 (July 30, 2006): Spirit acquired flat-field images for
calibrating variations in the field of light in the McMurdo panorama.

Sol 916: Spirit surveyed the sky and ground using the miniature thermal
emission spectrometer.

Sol 917: Spirit searched for clouds using the navigation camera.

Sol 918: Spirit added some finishing touches to the McMurdo panorama.

Sol 919: Spirit added more finishing touches to the McMurdo panorama.

Sol 920: Plans called for Spirit to conduct a photon transfer
observation to measure electronic noise (unwanted signals) picked up by
CCDs (charge-coupled devices -- imaging sensors that convert light into
electrical current) in the microscopic imager.

Sol 921 (Aug 5, 2006): Plans called for Spirit to acquire panoramic
camera images of a soil target known as "Tyrone."

Odometry

As of sol 918 (Aug. 2, 2006), Spirit's total odometry remained at
6,876.18 meters (4.27 miles).

------------------------------------------------------------------------

OPPORTUNITY UPDATE: Opportunity Examines Crater Ejecta, Grinds into Rock
- sol 893-899, August 04, 2006:

After traversing the sandy plains of Meridiani to "Beagle Crater,"
Opportunity investigated a patch of outcrop pavement thought to be
representative of the Martian surface beyond the reach of materials
excavated by the impacts that dug Beagle and the nearby, much larger
Victoria Crater. Opportunity used its rock abrasion tool to grind away
the surface of rock for the first time since the rover's 691st sol, or
Martian day (Jan. 3, 2006).

Both before and after grinding beneath the surface of the rock target
known as "Baltra," Opportunity took microscopic images and collected
data with the alpha particle X-ray spectrometer and the Moessbauer
spectrometer. The rover remains healthy. This weekend, the science team
plans to launch a three-day imaging campaign of Beagle Crater and the
surrounding area.

Sol-by-sol summaries:

Sol 893 (July 29, 2006): Opportunity took microscopic images of Baltra
and the grinding bit on the rock abrasion tool, ground 3 millimeters
(0.12 inch) beneath the surface of Baltra, and took images of the
magnets on the rock abrasion tool both before and after the grind. After
communicating with NASA's Mars Odyssey orbiter, the rover began a study
of Baltra with the alpha particle X-ray spectrometer and surveyed the
sky and ground with the miniature thermal emission spectrometer. The
rover turned off the alpha particle X-ray spectrometer at 11:13 p.m.,
local Mars time, before going into a mini-deep sleep.

Sol 894: Opportunity took stereo microscopic images of Baltra following
the grind. The rover spent 12 hours collecting data from the freshly
ground surface with the Moessbauer spectrometer. Opportunity acquired
panoramic camera images of the rim of Beagle Crater and a transitional
area around Beagle Crater known as "Espa?ola."

Sol 895: Opportunity acquired panoramic camera images of a flat rock
target known as "Bartolom?" and conducted Moessbauer analysis of Baltra.
Opportunity completed a very long survey of atmospheric dust, known as a
tau measurement, with the panoramic camera and surveyed the sky and
ground with the miniature thermal emission spectrometer. The rover went
into deep sleep to recharge the batteries.

Sol 896: Opportunity rolled back 1 meter (3.3 feet) and acquired color
images of Baltra using all 13 filters of the panoramic camera, then
drove 21 meters (69 feet) toward the edge of Beagle Crater. At the end
of the drive, the rover acquired images of the terrain using the
navigation and panoramic cameras.

Sol 897: Opportunity recharged the batteries and conducted untargeted
remote sensing of infrared energy and dust using the miniature thermal
emission spectrometer (beginning with looking at the calibration target)
and the panoramic camera. The rover surveyed the ground and sky with the
miniature thermal emission spectrometer while communicating with the
Odyssey orbiter.

Sol 898: Opportunity acquired panoramic camera images before driving 5
meters (16 feet) toward the rim of Beagle Crater. After the drive,
Opportunity acquired images with the navigation camera and data with the
miniature thermal emission spectrometer.

Sol 899 (Aug. 4, 2006): Plans called for a deep sleep followed by
turning on the miniature thermal emission spectrometer heaters at 7
a.m., surveying the sky with the panoramic camera, and collecting data
from the sky and ground using the miniature thermal emission spectrometer.

Odometry

As of sol 897 (Aug. 2, 2006), Opportunity's total odometry was 8,681.96
meters (5.39 miles).
Received on Fri 04 Aug 2006 12:18:35 PM PDT