Even though the Martian sky above Gusev Crater continued to clear, solar power levels on NASA's Spirit rover remained fairly constant as dust settling from the atmosphere accumulated on top of the solar panels. Activities remained restricted. Measurements of atmospheric opacity, known as Tau, dropped from 3.6 on Martian day, or sol, 1283 (Aug. 12,
2007) to 3.3 on sol 1286 (Aug. 16, 2007), generating power levels of 301 watt-hours (100 watt-hours is the amount of energy needed to light a 100-watt bulb for one hour).During recent wind storms on Mars, some dust appears to have gotten past the cover of the microscopic imager, based on images Spirit acquired on sols 1279 and 1284-1286 (Aug. 8, 2007 and Aug. 14-16, 2007). Engineers conducting tests with a surrogate rover on Earth hoped to position the instrument in a downward-facing position as early as sol 1290 (Aug.
20, 2007) in an attempt to get accumulated dust to fall out.While assessing the well-being of the microscopic imager, Spirit completed an analysis of a crushed rock target known as "Innocent Bystander" with the Moessbauer spectrometer and continued to make observations of the ground and atmosphere. The rover remains healthy and is parked just east of the elevated plateau known as "Home Plate."
The forecast for the next week is for no new dust storm activity, based on weather reports provided by Malin Space Science Systems, the builder of the Mars Color Imager on board the Mars Reconnaissance Orbiter. The camera is being used to monitor conditions on the red planet. Skies are expected to continue to clear over the next couple of months.
Sol-by-sol summary:
Except where noted, daily communications included morning, direct-from-Earth uplinks over the rover's high-gain antenna and evening relays of data to Earth at UHF frequences via the Odyssey orbiter. In addition, Spirit completed the following activities:
Sol 1284 (Aug. 13, 2007): Spirit placed the Moessbauer spectrometer back on Innocent Bystander and began analysis with the instrument. The rover also acquired images of ripples using the front and rear hazard avoidance cameras and microscopic images looking toward the sky through the dust cover of the microscopic imager. Spirit measured atmospheric opacity with the panoramic camera and surveyed the sky and ground with the miniature thermal emission spectrometer.
Sol 1285: Spirit surveyed atmospheric opacity with the panoramic and navigation camera and acquired images of ripples using the front and rear hazard avoidance cameras. The rover acquired microscopic images looking through the dust cover of the microscopic imager and surveyed the sky and ground with the miniature thermal emission spectrometer.
Sol 1286: Spirit surveyed the sky and ground with the miniature thermal emission spectrometer and measured atmospheric dust with the panoramic and navigation cameras. The rover continued with Moessbauer analysis of Innocent Bystander and took diagnostic images at different times of day looking skyward through the dust cover with the microscopic imager. Spirit surveyed the sky and ground with the miniature thermal emission spectrometer and acquired images with the front and rear hazard avoidance cameras.
Sol 1287 (Aug. 17, 2004): Spirit surveyed the sky and ground with the miniature thermal emission spectrometer and measured atmospheric dust with the panoramic and navigation cameras. The rover continued with Moessbauer analysis of Innocent Bystander and acquired images with the front and rear hazard avoidance cameras. Spirit took more skyward-oriented images through the dust cover with the microscopic imager and surveyed the sky and ground with the miniature thermal emission spectrometer.
Odometry:
As of sol 1287 (Aug. 16, 2007), Spirit's total odometry remained at
7,153 meters (4.44 miles).