Pre Downlink Meeting

Sol 23 was a drive sol with the objective of moving to a position where the "black lab" rock target within the arm work volume. Additional MiniTES and IPS observations of the Camelback target were acquired to characterize the stratigraphy and composition of these rock layers.

A high priority objective for the remaining mission is still to reach a suitable rock for in-situ measurements. The decreasing rover operation time and power resources continue to be a major issue in planning. Also, Sol 24 is a low rate DTE link. Long Term Planning is studying four options for the remaining sols of the mission: 1) "black lab" is within the arm work volume; 2) "black lab" is within one meter of the arm work volume; 3) "black lab" is further than one meter away; and 4) that there are no rocks near the rover.

Resource Predictions: 677 Whrs, 34 m DSN coverage, 3.06 Mbits DTE, 41.7 Mbits UHF, 50 minutes rover operations time with 13 pancam wedges that may still be stored in UHF buffer. If the MiniTES is maintained for operations on Sol 25, then the available UHF is reduced to 20.85 Mbits.

Mission Success at start of Sol 24: The rover has traversed 201.8 meters of the 200 meters needed for mission success. The mission has achieved the pancam panorama, 3 location, and trench criteria. Note that 2 trenches have been dug. Thus, all mission success criteria have been met or exceeded.

Science Assessment Meeting

Sol 24 will likely be an approach sol onto the "black lab" target, which is 1.28 meters from the current rover position. There is an opportunity for a touch and go observation with the IDD before approaching "black lab". Possible targets within the arm work volume include soil patches and several dark rocks. The Long Term Planning group is still debating whether it is feasible to use the RAT on "black lab", which is at the lower size limit for a RAT target.

Measurements of the pancam calibration target suggest that the rover coordinate system is offset from the true orientation by about 55 degrees.

Engineering reported that all commands from Sol 23 executed successfully and that the rover was in good health. All expected DTE data were received. Because Sol 24 is a low DTE sol, engineering has agreed to reduce their data allocation to 1 Mbit with the understanding that the data saving would be used by the science team to return two front hazcam images on the DTE link.

There also appears to be 13 pancam wedges that may not have been returned. They may be the UHF buffer on the rover or on relay orbiter. The SOWG chair decided that these data were not of high enough priority relative to the current resource limitations. Therefore, a command will be sent to the rover to flush its UHF buffer.

SOWG Meeting and Sequence Summary

It was agreed that Sol 24 would be an approach to the "black lab" rock target. The approach will require moving the rover forward approximately 35 cm from its current location. A touch and go sequence, along with MiniTES measurements of nearby soil and rocks will be done before the drive. Post-drive navcam data for planning remote sensing targets on the next sol was also deemed to be high priority.

Rover operation time and the power needed to maintain the MiniTES at its operating temperature continue to be the major constraints on science planning. It was agreed that trying to keep MiniTES operational until the Sol 24 observations were returned was an important goal. However, if the highest priority data needed for arm deployment on "black lab" or for remote sensing target planning cannot fit within the reduced UHF resource, then the MiniTES would be turned off.

The uplinked sequence planned given these constraints included:

• Six MiniTES observations were planned to determine the composition of nearly rock and soil targets including the "black lab" rock target. No supporting atmospheric MiniTES observations were planned.
• An IPS horizontal scan with 5 measurements was designed to study the composition of sediment in a dry channel.
• A touch and go sequence to collect APXS (short integration in Xray mode), MB (short integration) and MI data was targeted for the small dark rock, named "Darth Vader". Only one hazcam showing the placement of the APXS fit within the available data resources.
• An approach of 35 cm to the rock target "black lab" was planned. Front and rear hazcam images were acquired after the drive.
• A post-drive navcam mosaic covering the Camelback feature, which is needed for targeting remote sensing observations on the next sol, were acquired.
• After the drive, a pancam image the calibration target was requested to establish the rover orientation.

Post Uplink Informal Review

The previously acquired pancam wedges that were thought to be in the buffer were received on the Sol 24 UHF link and it appears that the buffer is now empty.

The data volume from the commanded sequence fit into the reduced UHF prediction, which means that the MiniTES can be kept operating for another sol.

The navcam mosaic needed for remote sensing targeting will be returned on the UHF link. However, planning of Sol 25 remote sensing observations will have to be done using the existing pre-drive navcam data. The mission manager agreed to allow the Sol 25 SOWG chair to use navcam data returned on the Sol 25 UHF link to adjust the targeting during the IST meeting. There is a risk in missing targets if the navcam data are not received on the UHF link. This approach was allowed because of the declining operation time and data resources and because the end of the mission appears to be near. This approach would most likely not have been allowed earlier in the mission.

An updated rover orientation was given as +65 +/3degrees relative to the SAP orientation.

A requested navcam/pancam sky survey sequence had to be deleted in order to have enough resources to accomplish the touch and go and the drive.

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