Sol 16 Summary

Science Assessment Meeting Summary

Engineering analysis of the telemetry indicates that the rover exceeded the time allotted for operations and the sequence was aborted on the last IPS acquisition of the Stoney Point array. All commands after this were not executed (Navcam wedge for IPS pointing and a front hazcam image), and a contingency sequence consisting of a 180d Navcam was acquired. The resource problem arose because 2000 coadds for the IPS unexpectedly takes more than twice as long as the typical 1000 coadds. The rover is healthy and ready for any operations on sol 16.

Preliminary examination of Sol 14 UHF and Sol 15 DTE data show that all IPS data look good and retakes are not needed on sol 16. Some initial indications of carbonate are seen, nut more time is needed for analysis. MB results from Snow White show montmorillinite, ferric material (hematite or geothitite) and kaolinite, so overall we have smectite. Compare with soil sample from sol 7 which indicated hematite, goethite possible with aluminum substitute, and three other silicates (muscovite, etc.) (see Mineralogy STG notes). APXS shows composition consistent with clays and consistent with sandstones and no carbonate. The Mineralogy STG thinks we have enough

The Atmospheres STG Moon observation missed, which indicates a problem with rover knowledge of sun. This is a potentially critical problem. LTP STG is working on a long traverse for sol 16 since general consensus is that this will be a drive day.

SOWG Meeting and Sequence Summary

Engineering analysis since the Science Assessment meeting shows that the rover sun sensor is not locking onto the sun. As a result, the rover heading is off, as was noticed by the SOWG at the end of Sol 14. Currently, the rover heading is about 50-60deg off. This has no effect on traversing except for decreasing the quality of the localization after a traverse, but it is the reason the Atmospheres STG cannot hit the Moon with its observations. It should be noted that during MER, if the sun’s location were lost, the HGA could not be pointed at Earth, and we would lose DTE uplink and downlink, and this would be a mission critical anomaly. However, this anomaly does not currently affect communications.

The SOWG agreed that we now have enough data to characterize the local area, so sol 16 was a drive sol toward the Field Goal/Guy in Stands area south of the lander. A 75 m traverse was initially planned, but this was reduced to a traverse of approximately 45 m straight line distance. Before traversing, MiniTES observations of Desert Tortoise (green shale unit from Pancam), the atmosphere 30 elev to east (high priority if other targets are distant to correct for downwelling radiance), Calico (light colored Bonneville stuff to check for homogeneity), Goose Prarie (gravel bar), and Wenatche were acquired. A sky survey observation searching for the sun was also conducted since the sun sensor problem could become critical in the near future. Other remote sensing observations were eliminated to allow the needed time for the traverse.

During the traverse, front and rear hazcams were acquired at each waypoint, and a request was put in to UHF downlink all traverse hazcams. At the end of the traverse a 360d Navcam was acquired, and another sun search was conducted.

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