We squeezed a lot of good science observations into the Sol 88 plan, and I'm happy with it. There were a lot of conflicting requests from the science theme groups, but we got most of them into the plan, including both arm and remote sensing activities. The only instrument that will not be acquiring new data is CheMin. I'm getting more used to the compressed tactical schedule and the tools we need to enable remote operations. So is the rest of the operations team, which is good because most of the science team will be leaving JPL next week.

The MAHLI "self portrait" of the rover that we planned on Sol 84 came out beautifully . Several other updates on the MSL mission are related to the news conference this morning, which included discussion of SAM atmospheric measurements. The SAM data indicate that much of Mars' atmosphere has escaped , as suspected based on previous studies. The rate of atmospheric escape is greater on Mars than on Earth because of the difference in gravity--if you weigh 100 pounds on Earth, you would weigh only 38 pounds on Mars. This difference makes it easier for gas molecules to fly away from Mars, and for the effects of these losses to be measured.

I served as SOWG chair today, and struggled to catch up with what had happened in the 2 days I took off since my last tactical shift. Fortunately, there were several people at JPL who had been working operations while I was away, and they helped me get up to speed quickly. The reports saved each sol on the team web site were also helpful, as usual, and will become even more important as we transition to remote operations next week.

We continue to prepare for the first delivery of a sample of Mars to SAM, the big analytical chemistry instrument on MSL. CheMin already analyzed its first soil sample , and SAM is next. The SAM "pre-conditioning" was successful, so the next scoop of soil will be delivered to SAM. As MAHLI PUL for the last time this week, I helped plan a "self-portrait" of the rover from the camera on the end of MSL's arm. It should yield a nice view of the entire rover, including the remote sensing mast that holds the cameras that usually take pictures of the rover: the stereo Mastcams and Navcams, and the ChemCam LIBS and camera combination. It addition, we planned more stereo images of the rocks right in front of the rover to extend the topographic map of the area surrounding them. This map is needed to ensure that the arm instruments (especially APXS) can be deployed on these rocks.

The MAHLI images of the rocks right in front of the rover came out nicely and are being processed to enable APXS placement on one or both of them. The Sol 83 plan focused on SAM and CheMin activities, in preparation for the next scooping and delivery of soil to those instruments. So there wasn't much room in the plan for anything else, and no new MAHLI images were planned. I had an easy day, but have to start my next MAHLI PUL shift at 4:30 tomorrow morning. It will be my last PUL shift on Mars time, and the last difficult start time for me. While I'm looking forward to returning to a normal schedule, I'll miss the excitement of working with the whole team at JPL. After Sol 90 the plan is for most of the science team to return to their home institutions and support rover operations remotely. More on that later...

MSL operations have gone well while I was in the Bay Area: the team applauded the successful completion of CHIMRA cleaning today. As a bonus, almost 1 gigabit of data were received on Sol 81! I was MAHLI payload uplink lead for Sol 82 planning, and had to scramble to get up to speed after being away for a few days. A lot of good MAHLI observations were proposed, and most of them made it into the plan: Stereo observations of two rocks near the left front wheel that cannot be well imaged by the Navigation cameras, and a couple images of the latest scoop trench. The stereo MAHLI images will hopefully be useful in determining whether the APXS can measure the chemistry of these rocks.

Mars time is getting closer to Pacific Daylight Time these days--my shift didn't start until 6:30 this morning. We will receive data from MSL even earlier tomorrow morning, so I have to arrive at JPL at 5:45 AM. But we will not be working on Mars time for long--the plan is to transition to "Earth time" by Sol 90.

I'm not at JPL for the rest of the week, but was glad to see that the ChemCam shot at the soil near MSL went as planned on Sol 74. Since then, more observations of the ChemCam calibration targets have been successfully acquired, which is good news because the calibration is long overdue. Also, a Mastcam image of the latest soil scoop was returned .

As the MSL operations team gets more experience, we are getting more aggressive. In addition to the long-planned arm activities (4th scoop of soil), we added MAHLI images of the far side of the ripple we are scooping, Mastcam mosaics, and ChemCam LIBS observations of a nearby patch of soil during the day and just before dawn. The ChemCam observations are intended to see whether water frost forms on the surface during the night, by comparing the amount of hydrogen seen in the LIBS spectra when the soil is warm and cold. It was my last sol as SOWG Chair, and I was happy that we were able to squeeze so much into the Sol 74 plan.

I'll be taking a few days off from tactical operations this week, traveling to the Bay Area to give an overview of the Curiosity mission at the USGS in Menlo Park.

The team applauded the first results from CheMin, which show that the instrument is working well, measuring abundances of minerals in the sandy first sample delivered to it. The CheMin scientists thanked the Surface Sampling Subsystem team for doing such a good job delivering the first sample, and there was another round of applause.

The plan for Sol 73 is dominated by more arm activities, processing another scooped sample through CHIMRA to further clean out any terrestrial contamination before a sample is delivered to SAM, which is very sensitive to organic material. We don't want to put any organic material from Earth into SAM! There wasn't much room in the plan for additional science observations, but we were able to squeeze in a MAHLI image of the observation tray to see whether the soil placed on it during Sol 70 slid or blew off the tray.

MRO is back--we received over 400 Mbits of data through the orbiter yesterday! The amount of data relayed through MRO will decrease once the orbiter's instruments are operating again (they were turned on this morning), but in the meantime we're enjoying the flood of data. Among the new data were 810 ChemCam laser shots acquired on Sol 71--a new record for a single sol. For Sol 72, we planned a raster of ChemCam laser shots of the bright particle "Schmutz2" in the second scoop trench . And the much-anticipated first mineralogical analysis by CheMin was planned to run into the early morning of Sol 73.

"Mars time" is rough for those of us on first shift these days: The daily "science discussion" started at 10 PM PDT, and I wasn't done with SOWG Chair duties until 7:30 this morning. It didn't seem fair that I got caught in morning rush hour traffic on my way home! But I've realized that this may be the last time I'll work on "Mars time" in my career--it looks like there will not be another NASA spacecraft landed on Mars this decade--so I'm trying to enjoy it. In fact, I'm getting used to being a Martian, even though sleeping during the day is difficult.

The third scoop of soil was successfully acquired, and partly processed by CHIMRA, dumping part of it on the observation tray . So MSL is back on track despite the unavailability of MRO data relay and other communications problems. MRO has exited safe mode and is expected to resume relaying MSL data today. The plan for Sol 71 is to use CHIMRA to sieve the sample and deliver it to CheMin, the mineralogy instrument inside the rover. It will be the first Mars sample for CheMin, an event that has been eagerly anticipated. The Mastcam will then take pictures of CheMin's sample inlet to confirm that all went well. Other Mastcam and ChemCam observations were also planned for Sol 71. I was not scheduled in a tactical role the past 2 sols, so have been catching up on other work before I'm back on as SOWG Chair for Sols 72-74.