The first round of SAM experiments was successful, so in the weekend plan we get to move forward with the GCMS (Gas Chromatograph Mass Spectrometer) experiment. First, additional sample will be delivered to SAM. Then the sample will be heated and analyzed. This is exciting because we decided to drill the Kilmarie target after the Aberlady drill hole did not yield enough material for us to be confident that there would be enough sample for SAM. With the first SAM experiment complete and the second experiment in the weekend plan, things are looking good so far at the Kilmarie drill hole.

In addition to the SAM experiment, ChemCam is going to be busy this weekend. ChemCam will target "River Spey," a light-toned vein near the drill hole, and "Rothes," a small block that exhibits laminations. Finally, ChemCam will re-target "Tiffany." Tiffany is a pebble that was targeted earlier this week, but we missed by a little bit because it is such a small target. Since we are sitting in the same location for a while during the drill campaign, ChemCam has the opportunity to redo this observation, now called "Tiffany 2." Mastcam will take documentation images of each of the ChemCam targets.

Today I was the MAHLI/MARDI payload uplink lead. Since there was no MAHLI or MARDI in the plan, my day was pretty simple. There will be plenty of MAHLI activities in a future plan once the laboratory experiments are done and we need MAHLI images of the drill hole, so my role will be busy soon!

The drop off of "Kilmarie" drill sample to SAM on Sol 2293 appeared to be successful, but we will not get the full results of the SAM analysis until later today. The results are needed to help determine if we will dive even further into the volatile and organic makeup of the Kilmarie sample. There was no sitting around and twiddling actuators, however, even though the amount of power available was limited. Curiosity will gather more details about the Kilmarie sample mineralogy via another CheMin integration, and also pepper a suite of broken up bedrock fragments around the rover - "Deinabo," "Durnhill," and "Dumyat" - with ChemCam shots to compare their chemistry to that of the more-coherent bedrock that Kilmarie is found within. The rover will acquire a long distance RMI mosaic looking uphill toward the part of the Mount Sharp stratigraphy that is observed to have a strong spectral signature of sulfate from orbit. Changes caused by the wind will be monitored by comparing the single MARDI image acquired in this plan to one acquired right after our arrival at Kilmarie on Sol 2381. Changes in the environment will be monitored with a Navcam cloud movie and regular REMS and RAD measurements.

Today's main activities use the "laboratory" instruments SAM and CheMin inside of Curiosity to analyze some of the powder from the Kilmarie drill hole. SAM will do an Evolved Gas Analysis, which involves heating the sample and measuring the gases that are generated, and CheMin will do its usual analysis, shining x-rays through the sample to determine what minerals are present. Power was on the low side today, and initially we thought there wouldn't be much of a chance to do other science, but our resourceful team was able to fit two small science blocks into the plan.

On sol 2393 the afternoon science block is dedicated to atmospheric observations. Navcam will watch for dust devils and clouds, and Mastcam will look at the sun and the sky to figure out how much dust is in the atmosphere and what its properties are.

On Sol 2394, Navcam will do two more dust devil surveys, and then ChemCam will take over. ChemCam will do a passive (no laser) observation of the Kilmarie drill tailings, and then will zap two bedrock targets, "Tolmount" and "Tiffany," to continue to document the variable bedrock chemistry in the area. Mastcam will then take a picture documenting the two ChemCam targets.

We won't be done with SAM and CheMin after today's plan: we expect to continue to analyze the Kilmarie samples for several more days. These laboratory analyses drain a lot of power, but they really tell us a lot about the rocks we're sitting on. Especially for these drill samples in the "clay-bearing" unit that we've been striving to reach since landing, it's worth taking our time to do things right!

Navcam Right image showing the newest "Kilmarie" drill hole on the right, <1 m away from the "Aberlady" drill hole on the left.

We started planning in eager anticipation of the preliminary results from our downlink and whether the CheMin X-ray diffraction spectrometer received enough sample of the "Kilmarie" drill sample to successfully complete a first night of analysis. Less than 40 minutes after downlink, we got confirmation from the CheMin team that they did indeed receive enough material. This meant that we could proceed with the two highest priority activities in the plan; the second night of CheMin analysis of the Kilmarie drill sample, and a SAM preconditioning activity in preparation for delivery of sample for a SAM Evolved Gas Analysis (EGA) experiment in the coming week's plan. The CheMin instrument informs us of the mineralogy of the sample, which can give us clues about the source of the rock sample, the conditions under which it formed and any subsequent alteration events. It will be interesting to compare the mineralogy of Kilmarie with the nearby "Aberlady" drill hole. The SAM EGA experiment will measure the composition of the different gases evolved at different temperatures as the sample is heated in the SAM oven. This complements the CheMin data and can help refine the mineralogy and tell us about the amount and nature of S, N, H, Cl, O and C associated with the various minerals. We are particularly interested in whether this sample from the "Clay-Bearing Unit," Glen Torridon area, does in fact contain clay (as have the majority of drilled samples), and if it does, how much is present and what type of clay mineral is it?

The science team also planned ChemCam LIBS on four rock targets ("Mile End," "Tillyfourie," "Tillybrachty" and "Tillymorgan") in the vicinity of the drill hole to continue to monitor compositional variation between relatively coherent and more rubbly bedrock that we have been observing within Glen Torridon. We will also acquire Mastcam support imaging for the ChemCam targets as well as a large multispectral mosaic in the direction of the "Greenheugh Pediment" and "Sulfate-Bearing Unit" that we will eventually drive to. The multispectral mosaic will help to highlight possible spectral and mineralogical differences between the different coloured strata we observe in this area.

Today was also a busy planning day for environmental observations with three science blocks devoted to these activities. A ChemCam passive sky measurement was included to look at water vapour and aerosols in the atmosphere above Curiosity, as well as Mastcam tau observations to measure the atmospheric opacity and a large Navcam dust devil survey. Navcam zenith observations were also planned as part of the ongoing campaign to monitor martian clouds. Standard background REMS activities monitor the daily martian weather and we continue to monitor the radiation environment with RAD and the abundance and distribution of H- and OH-bearing materials within the subsurface with DAN passive activities.

As the APXS strategic planner tosol, I have been able to focus on monitoring all of the other science activities taking place to write this blog, as there was no APXS. We have to wait to use the arm, and MAHLI and APXS on the end of the arm, until after we have dumped the Kilmarie drill fines from the drill bit assembly. This does not occur until the SAM and CheMin instrument teams confirm that they do not require any more sample.Both the MAHLI and APXS teams eagerly await the chance to analyze the drill fines from this latest hole on Mars.

In the plan today, the top priority was to drop off some sample from the Kilmarie drill hole to the CheMin instrument in order to begin the process of obtaining quantitative mineralogy. The CheMin instrument will help determine how the elements that make up the Kilmarie drill sample are bonded together, not just the abundances of the elements in the rocks like the ChemCam and APXS instruments can determine. Figuring out how the various elements are bonded together is particularly important for geologists as it tells us more about how the rock formed and its alteration history than the elemental chemistry alone. When coupled with the ChemCam and APXS chemistry information these datasets becomes particularly powerful.

In addition to a suite of ChemCam observations planned to help finish characterizing the workspace and the two Kilmarie and Aberlady drill holes, a large Mastcam mosaic was planned of a nearby aeolian ripple field. This large mosaic, where multiple images (in this case 120) will be taken using precise movements of the Curiosity rover's mast will take
nearly one hour to complete. Mosaics like the one in today's plan are not all that common in planning for several reasons. Not only do these large mosaics take a long time and thus require a lot of power but they also produce a lot of data that has to be downlinked to Earth. Each of these constraints must be considered carefully when planning a large mosaic. Included is one of the 120 images acquired as a part of the mosaic.

The drilling planned for last weekend was successful, so the top priority for Sol 2386 is to drop portions of the Kilmarie sample onto a closed SAM inlet cover and take Mastcam images after each dropoff to characterize the size of each portion. The results of this portioning test will be used to decide how many portions to eventually drop into SAM. After this testing is completed, Mastcam will measure the amount of dust in the atmosphere above MSL by imaging the Sun through neutral-density filters, and Navcam will search for clouds. Then the ChemCam RMI will acquire a "stack" of images of the Aberlady drill hole at various focus settings to find the best focus setting for future LIBS elemental chemistry measurements from our new vantage point. The RMI will also acquire a couple mosaics of the sulfate-rich rocks exposed in the distance southeast of the rover. Mastcam will measure variations in sky brightness to constrain the size of dust grains suspended in the atmosphere before the rover takes a long nap. Late that evening, CheMin will vibrate its inlet sieve and dump the Aberlady sample in preparation for analysis of the Kilmarie drill sample.

On Sol 2387, Mastcam will again measure dust opacity and Navcam will search for dust devils and clouds. ChemCam will then use its laser to measure the elemental chemistry in the wall of the new Kilmarie drill hole and of a nearby pebble named "Quirang" and a bedrock outcrop named "Caledonian Canal." The Right Mastcam will image all of the ChemCam targets before DAN turns on its neutron generator to search for hydrogen up to half a meter below the surface.

It was a quiet day for me and the other MAHLI/MARDI uplink leads, as MAHLI activities are precluded while there is sample in the drill stem. Still, it was interesting to follow the tactical planning today!

Yestersol's drill pre-load test was successful, so today we are go for a drill attempt at "Kilmarie!" The front hazcam image from yesterday's test (shown above) is a helpful visual for understanding how close our new drill location will be to the last drill at "Aberlady." In this image, you can see Curiosity resting the point of the drill on the future Kilmarie drill target along with the old Aberlady drill hole, a little to the left of the arm. It's been a while since we've drilled two locations so close together! Avid readers of this blog will recall we decided to drill again in this area because we saw some irregularities during drilling Aberlady. Specifically, we weren't sure we'd collected enough drill material for both CheMin and SAM analyses at the Aberlady location, so we're hoping we can be more confident in the amount of sample we collect at Kilmarie.

I was staffed in the role of Surface Properties Scientist (SPS) during planning yesterday and today. One of my responsibilities as SPS is to help assess whether the terrain Curiosity is parked on is stable. Curiosity's arm is so big and heavy that moving it causes the rover's center of gravity to shift. If Curiosity isn't firmly parked, moving the arm could inadvertently move the entire ~1 ton rover, which could result in hardware damage. Yesterday, we determined Curiosity had parked on a flat surface and five of the wheels were firmly in contact with the ground. However, the right front wheel appeared to be sitting on a very small rock (~2-3 cm) that was located right in the middle of the wheel. We had a lot of conversations about what the risk of the vehicle slipping was and whether we thought the rock we were sitting on might shift. Using our experience testing similar situations in the Mars Yard at JPL and knowledge of properties of the terrain around the rover, we decided the risk we'd slip was very small, and gave the "OK" to go ahead with arm activities. Images taken before and after the drill pre-load yesterday confirmed we hadn't moved at all and were correct in our assessment.

Image taken by the Front Hazard Camera on Sol 2381 (2019-04-18 14:51:13 UTC). It shows the rover in its new position at target "Kilmarie," which is on the small triangular block in the center of the field of view.

Some days just give me goose bumps. First, looking at yesterday's plan I realized that we did something really unusual overnight: Wrap up the drill activity on one site and start the drill activities on the next in the same sol. As reported yesterday, we said Good-bye to "Aberlady," and we turned the rover to "Kilmarie," our next drill target. The two targets are just 80 centimetres away from each other.

But that was not the only thing that made the day special. On some days we start planning just before the MRO (Mars Reconnaissance Orbiter) data downlink is due to deliver the data that we need for planning. Today was such a day. Seeing the data arrive, displaying them the moment they show up, and discussing what we see immediately after the data reached us, is one of the most exciting moments of such a planning day. But there wasn't much time to think about emotions, because we were looking at the next step of the drill activity and needed to assess the options on the block we had just successfully bumped to.

Discussions started immediately, and a sol full of activities was planned. The sol plan begins with the preload test on the "Kilmarie" target drill candidate. This is to see if the rock will withstand the pressures during drilling. MAHLI images document the outcome of the test. If successful, drilling will follow. The next activities in the plan include two LIBS ChemCam activities and accompanying Mastcam documentation images on the targets "Udny Green" and "Green Craig." They are both targeting the pebbly materials as we need to understand its composition better, especially if all of the material has the same chemistry, or what the differences might be. The rover is then set to be busy overnight with an APXS on the "Kilmarie" target, getting two slightly offset measurements to characterize the composition of our new drill target candidate.

Curiosity is finishing up at "Aberlady" and ready to move on to our next drill target. We are preparing to drill a second hole in the clay bearing unit. Reaching this region, and drilling has been a goal since Curiosity landed over 6 years ago (Sol 2369-2371:This is why we came to Gale.) We were already successful drilling once, and now we will attempt to drill for a second time. Anytime we drill, we take a few sols to prepare. Tosol is considered drill sol 0.

Before we say goodbye to "Aberlady" and move on, we will use MAHLI to image the drill cuttings from "Aberlady." After that the arm will retract and be stowed. To get to our next target, Curiosity needs to drive less than 1 meter to get into position. These short drives are called a "bump." After the bump, we will take Mastcam images, MARDI image, and turn DAN on active mode.

Yesterday's discussions with the science team focused on determining which target in the vicinity of "Aberlady" will become the focus of the next drill campaign: target 2, or target 3 (pictured in the Sol 2379 Mission Update). In the end, target 3 was recommended by rover planners for its flatter texture, as an APXS raster of both targets showed there wasn't a large difference in composition between the two. Once formally included in plan activities, target 3 will be given a proper name consistent with those being used in the "Glen Torridon" region.

Tosol begins with a MAHLI open cover image of the Aberlady sample dump pile (shown above) and then an arm retract to get it out of the way for a Mastcam multispectral observation of the dump pile that follows. Next, a Navcam dust devil survey and suprahorizon movie are included to monitor clouds and dust devils in the current transition from dusty to cloudy season. Then a ChemCam 10x1 vertical LIBS and RMI observation on the Aberlady drill tailings and a Mastcam documentation image wraps up the 1 hour science block.

After sunset, two APXS rasters on two differently toned drill tailing targets are planned to run until the wee hours of the night, when CheMin will take over with its third integration on the Aberlady drill sample, using X-ray diffraction to identify the signals of the minerals present in the sample.

Standard DAN passives and REMS observations were included to continue monitoring the environmental conditions at the current workspace. Tomorrow the goal is to finish up at Aberlady, and bump to target 3 for "Drill Sol 0."