[meteorite-list] Mars Exploration Rovers Update - May 17, 2004

[Ron Baalke]

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

SPIRIT UPDATE: Spirit Spirit Roving Right Along - sol 127-130, 
May 17, 2004

Spirit spent most of sol 127 continuing its drive toward the 
"Columbia Hills." The rover put approximately 70 more meters 
(229.7 feet) on its odometer and then took an hour-and-20-minute 
siesta. After the drive, Spirit took observations with the 
panoramic camera, navigation camera and mini thermal emission
spectrometer.

Spirit began sol 128 by completing a panoramic camera 
observation of a rock target called "Flat Head." The rover then 
rested up for a couple of hours before embarking on a 90-meter 
(295 feet) drive toward the hills.  Once the drive was complete, 
Spirit completed its standard post-drive observations.

Sol 129 began successfully, but Spirit encountered a couple of 
difficulties before the martian day was over.  After waking, 
Spirit performed 45 minutes of science observations and then 
settled down for a morning nap.  With plenty of energy stored, 
it was time to drive. Spirit roved 31 meters (102 feet) across 
the surface in an engineer-directed drive and then spent 45 
minutes using its autonomous navigation system to try to drive
down the side of a small ridge. The backside slope of the ridge 
was too steep, and the autonomous navigation system had Spirit 
turn in an attempt to find another way down. Unfortunately, a 
couple of large rocks close to the ridge prevented Spirit from 
finding a safe path down. At the end of the drive sequence,
Spirit was supposed to complete a "stutter step" to get in 
proper position to do work with the instrument deployment device 
on sol 130. Unfortunately, the rover was unable to complete this 
final positioning or the ultimate post-drive imaging, so sol 130 
was mostly a drive sol.

Spirit has 2,291.92 meters (1.4 miles) on its odometer and is 
approximately 936 meters (.6 miles) from Columbia Hills. The rover 
is on track to reach the Columbia Hills by sol 160.



OPPORTUNITY UPDATE: Opportunity Digs, Scuffs, and Cruises. - sol 107-111, 
May 17, 2004

On sol 107, Opportunity successfully drilled a hole into "Lion 
Stone" with the rock abrasion tool. Since the surface of the rock 
was fairly uneven, the tool had to work through some high spots 
before getting a good bite on the rock for a full circular hole. 
Sol 107 ended at 6:44 a.m. May 13 PDT, with a nighttime 
integration of the alpha particle X-ray spectrometer to reveal 
elemental composition of the inner part of the rock.

On Sol 108, which ended at 7:24 a.m. May 14, PDT, the rover 
finished up its work on Lion Stone by analyzing the rock 
abrasion tool hole with the Moessbauer spectrometer and 
taking microscopic images to create a mosaic of the hole. 
Opportunity then moved away from Lion Stone and continued 
traversing counterclockwise around the crater. Opportunity 
drove 32 meters (105 feet) to the top of a small ridge for a 
better view of where to drive on Sol 109.

On Sol 109 and sol 110, which ended at 8:04 a.m. May 15, PDT, 
and 8:43 a.m. May 16, PDT, respectively, Opportunity drove about 
41 meters (135 feet) each sol. Opportunity ended the drive on 
May 16 with a "scuff" of the soil and rocks under the front wheel. 
This scuff action produced an interesting dislodged plate of some
kind. The scientists will be making some additional observations 
of different pebbles on the ground in the sol 111 plan.

Opportunity is driving along the south edge of Endurance Crater, 
with a southward tilt of about 8 degrees.  The Sun is now at 
higher latitudes (south hemisphere winter is coming), so a 
southward tilt robs the rover of total solar array energy. This 
is making it more difficult to perform many activities. In a 
couple of sols when Opportunity drives to flatter ground near 
the crater edge to take the next large panorama, the energy
situation is expected to improve.

Opportunity has driven a total of 1,170 meters (3,839 feet or 
0.7 miles).