Curiosity update, sols 1012-1072: Sciencing back and forth below Marias Pass

Since my last update, Curiosity has driven back and forth repeatedly across a section of rocks below Marias pass; in fact, there's one section of the trail that she has driven over five times. The science team finally drilled at a spot named Buckskin on sol 1060, a site with unusually high silica. The fact that they drilled at all is extremely good news, because they had not been allowed to use the drill for science since a troubling short circuit occurred on sol 911. With work at Buckskin complete, Curiosity has now (as of sol 1072) driven away from the science site and is back on the road, headed up and over Marias Pass. The road toward the mountain-encircling dark Bagnold dune fields ahead takes her into the "washboard terrain" -- now also referred to as the Stimson unit -- an erosion-resistant rock type that she'll have to pick over carefully to preserve the health of the wheels, and a likely future drilling target.

Buckskin makes seven spots that Curiosity has drilled since landing on Mars three years ago. Here they are:

Do you notice the subtle color variations among the drill tailings? Those variations are real, and are hints to varying rock composition. Here, Gerald Eichstädt has sorted them into a rainbow. Buckskin, near the center, is on the bluer end of the spectrum.

The area below Marias Pass has been a fun science stop. The key scientific question here is: what is the relationship between the underlying Pahrump formation and the overlying Stimson formation? Pahrump material is what Curiosity drilled into at Confidence Hills and Mojave. It is a light-toned, very fine-grained sedimentary rock that sometimes possesses very thin layering and erodes in interesting ways -- sometimes it makes a pavement, but it can also form heavily eroded outcrops of stacks of impossibly thin blades. The Stimson unit, above that, is more resistant to erosion. What made that change in petrology? Is it a change in climate? A change in depositional environment? Is Stimson also sedimentary? How much time separated Pahrump and Stimson? To answer all these questions, the science team needs to characterize both rock types and also find a spot where you can see the boundary separating Stimson and Pahrump.

My previous update deals with the challenges that the rover team had in getting to a location where they could see that contact. But they persevered and reached it just before solar conjunction temporarily shut down rover operations, from sols 1005 through 1026. On sol 1031, they took this stunning MAHLI panorama of the contact between Pahrump material, below, and Stimson material, above.

The image is much smaller than it looks, only about 40 centimeters wide. Stimson is sandstone, but at its base the sandstone is full of very small (millimeter-sized) nodules. Below it, the Pahrump material is thoroughly shot through with veins of calcium sulfate. The veins do not continue into the Stimson unit. That tells you something about the history here -- the Pahrump stuff formed first, became hard enough to fracture, mineral-rich water filled the fractures with calcium sulfate, and only after that did the Stimson stuff get deposited on top. I'm not sure how much time separated Pahrump and Stimson, but there's clearly a time gap of some length between the two.

[Edited August 15 to add:] However, it's been pointed out to me by Dawn Sumner that there are other places in the area where the mineral-filled fractures actually do extend upward into the Stimson unit. How could that be? Maybe the vein filling happened after both Pahrump and Stimson formed, but the upper unit is less permeable to water than the lower unit, so the veins couldn't propagate far. The question of the relative timing of Stimson and veins is definitely not settled. Nothing is ever as easy as one would like it to be!

High-Silica Target Spotted by Survey Instruments

Before conjunction, the likeliest scenario for Curiosity's future activities was that they'd drill into the Stimson unit (a rock type they hadn't seen previously), and then move on. But project scientist Ashwin Vasavada told me that during the downtime of conjunction, two different instrument teams discovered something exciting in their data from previous weeks. The two teams independently presented their discoveries of a weird rock type at a major Curiosity science team meeting. And they were both talking about the same location along Curiosity's traverse.

The discovery is summarized in a JPL news update: "NASA's Curiosity rover inspects unusual bedrock." Both ChemCam and DAN measurements revealed an area of bedrock within the Pahrump unit that had an unusual composition. ChemCam saw high silica -- higher than they'd ever seen at any other site -- while DAN saw high hydrogen, many times what they'd seen elsewhere. The rover would have to backtrack to reach it, so they did, in several drives beginning on sol 1035.

But reaching the rocks was a bit of a challenge. The drive back along her tracks to the northwest to the interesting rocks was on fairly flat ground along the crest of a local hill, but the high-silica rocks were located just below the hill's crest. Curiosity attempted to find a spot for in-situ work on a target named Lamoose on sol 1041, but the ground sloped downward too much for the arm to be able to reach it safely for contact science (though they were able to do stand-off measurements with ChemCam and APXS).

They had a decision to make. They could return to the location near Missoula and try drilling both Pahrump and Stimson units there. The Pahrump material near Missoula did have elevated silica, just not as high as what ChemCam had spotted in the area near Lamoose. And they do want to drill into Stimson eventually. Or, they could attempt to find a better contact science target near Lamoose. None of the bedrock in the area seemed very good for drilling. In the end, they decided to look for a high-silica drill target. So they turned around again, headed southwest for a second potential drill site at a location named Elk, which they reached on sol 1046. Again, they were frustrated; Ashwin told me they "couldn't even get the arm on Elk." They made one more effort, driving northwest again to reach a target region named Lion, and got there on sol 1051.

It had taken them more than two weeks to get there, but they finally found a site that looked drillable. And the delay wasn't all bad; it actually gave the rover drivers the time that they needed to do the testing and documentation necessary to win approval to begin using the drill again. They bumped to the target, named Buckskin, on sol 1056, drilled on sol 1060, and drove off on sol 1066, retracing her steps for a fifth time to drive on up into Marias pass.

They did not elect to stop and drill the Stimson unit after all. Ashwin told me that since they will be driving on it for a while, there was no urgency to drill into it at Missoula. It's clear that the mission science benefits when the science team is able to spend some time digesting data; the focus now is putting kilometers on the odometer. The rover drivers will be looking out for likely drill spots as they trundle along, a juicy target of opportunity that they can hit without too much effort (and certainly without having to drive back and forth over the same spot five times).

To me, the work below Marias Pass shows ChemCam and DAN working precisely as they were supposed to on this mission. DAN does active and passive scans for hydrogen in the subsurface throughout the traverse, while ChemCam can be used to zap rocks opportunistically at each place that the rover stops after a drive, surveying elemental composition. Each is capable of noticing unusual rock types, offering suggestions to the science team for targets that might be worth spending the extra effort to examine up close with the arm. The long, long drive from Yellowknife Bay to Pahrump Hills didn't offer ChemCam and DAN all that much variety, but now that Curiosity is driving up into the layered sedimentary rocks of Mount Sharp, the survey instruments are serving their function. Now we have to wait to see what SAM and CheMin tell us about the powder drilled from the high-silica target at Buckskin!

New Curiosity Capabilities: Cached Sample Operations and Opportunistic Mid-Drive Views

[This section has been edited with some corrections from rover drivers on August 15. More corrections are likely later.]

A sample delivery has already been made to CheMin, and SAM will likely receive its first sample within a week. Curiosity is driving with powdered sample from Buckskin held inside the CHIMRA sampling mechanism in the turret on the end of the arm, something called cached sampling. This is a technique that permits Curiosity to rack up the miles on the odometer while the scientists are making careful choices about all the different knobs they can turn on the SAM instrument to do the right kind of analysis for the sample. Caching sample in CHIMRA while driving is what enabled the mission to do all the especially cool analyses it performed on the Cumberland sample that yielded the age date, the chlorobenzene detection, and other cool science. But "the rover planners detest it," Ashwin told me. It was not a capability that Curiosity had landed on Mars with; the arm engineers developed it shortly after landing, after they arrived at the Rocknest sand dune, where the rover sat and sat for a long time through CheMin and SAM analyses.

The problem is that if you want to use the arm while there's sample inside it, you can't rotate it into certain positions or you risk damage to the interior of CHIMRA. Arm operations with cached sample had to be very careful what positions and orientations the turret moved through, to prevent hardware damage, and there were many activities that weren't permitted at all.

But maybe it didn't need to be so hard. The engineers had developed cached sample operations in a hurry at Rocknest, and when engineers are forced to hurry and lack the data they need to be confident in hardware safety, they are very conservative. They had had more careful analysis and testing of cached sample operations on their list of things to do for a long time, but other work was always more pressing. Finally, in the last six months, they were able to do work in the testbed on cached sample operations. They figured out something crucial: as long as the amount of material inside CHIMRA is sufficiently small, nearly every arm motion is permissible.

Another activity that Curiosity has been doing since leaving Pahrump Hills is to perform mid-drive remote sensing campaigns through gaps in the horizon. The team has performed viewshed analysis of the terrain that Curiosity is likely to traverse, using digital terrain models developed from Mars Reconnaissance Orbiter HiRISE images. Whenever Curiosity's path takes the rover past a topographic notch that allows a good view of the terrain ahead, the rover planners may drop a mid-drive Mastcam or Navcam observation into the sequence. These will help the science team tie the ultra-local geology that Curiosity can see from the valleys she drives through to the regional geology as seen in telephoto views of outcrops at some distance.

Five Times Back and Forth. Five.

The biggest challenge with writing this update has been figuring out Curiosity's path during the past month; there has been quite a lot of step-retracing. After looking at official maps, unofficial maps, Mars Trek, Midnight Planets, the Curiosity Tracker, and the USGS updates, I finally figured it out. There is one segment of the drive path that Curiosity retraced a total of five times.

• As of sol 997 (before conjunction), Curiosity was sitting at a site facing southwest up into Marias Pass, where she acquired a large MAHLI mosaic on "Missoula" on sol 1031.
• On sol 1035, Curiosity retraced her tracks to the northeast, to her position on sol 992.
• On sol 1037, the rover drove 5 meters, then backed down the slope a bit on sol 1039 for better stability; these locations were near the sol 991 spot.
• On sol 1042, the rover turned around and retraced her steps again, traveling southwest along the path she'd already traveled on sols 995 (to the southwest) and 1035 (to the northeast), but the drive faulted after 17 of 25 meters. They completed the drive on sol 1044 and continued the trajectory on sol 1046 to do wheel imaging and finish up next to a potential drill target named "Elk."
• Elk turned out not to be suitable for drilling, so on sol 1049, the rover turned around and retraced her steps again (this is four times along the same path now); the drive faulted a bit short of the goal, leaving her in a position adjacent to the one she'd been in on sols 992 and 1035. She finished the drive on sol 1051, aiming for an outcrop named "Lion."
• Short drives on sols 1053 and 1056 brought her to the target within the Lion outcrop named "Buckskin," where she drilled on sol 1060.
• After drilling, on sol 1066 she proceeded to the southwest again, returning to the locations she'd been on sols 1044 and mid-drive on sol 995 -- are you keeping track? This is the fifth time she passed this spot.
• A drive on sol 1067 returned her to the neighborhood of the base of Marias Pass, where she'd spent conjunction.
• Finally, on sol 1072, she drove southwest up into Marias Pass, leaving the science stop behind.

And that is why this update contains no route map. I was unable to develop a route map that made any sense in time for this to post. I may keep working on it and add it later.

That's it for this update; the next one will likely be a road trip report. Stay tuned! Here, as usual, is the text of all the USGS Astrogeology updates for the period covered in this blog post, written by Ryan Anderson, Lauren Edgar, and Ken Herkenhoff.

Sols 1027-1029 update by Ken Herkenhoff: Resuming tactical operations (26 June 2015)

Mars has passed through solar conjunction, and reliable communication with the spacecraft at Mars is possible again. As planning started this morning, we were still waiting for more data to be relayed by the orbiters to confirm that MSL is ready to resume science planning, but proceeded with tactical planning so that we would be ready when the data arrived. The Sol 1027 plan starts with Mastcam observations of several targets that were imaged just before solar conjunction, to look for changes caused by winds or maybe Marsquakes. Mastcam will then look at the sun to measure the amount of dust in the atmosphere, Navcam will search for dust devils, and ChemCam/Mastcam will observe nearby targets "Piegan" and "Wallace." On Sol 1028, the arm will be used to take MAHLI images of the rocks and soil in front of the rover from various vantage points, to measure changes in their reflectance with observation geometry ("photometry"). After dusk, APXS and MAHLI will measure 3 spots on a rock called "Big Arm" that was imaged by MAHLI during the day before solar conjunction. The nighttime images, using MAHLI's LEDs for illumination, should nicely complement the daytime images of the rock. Finishing off the weekend plan, on Sol 1029 ChemCam will acquire some calibration data and Mastcam will take a stereo mosaic of the outcrops to the east of the rover.

As SOWG Chair today, I was a bit worried about planning so many activities on the first day of tactical planning in a few weeks, but the team hit the ground running and did a great job. Early this afternoon, we got word from the downlink team that the data acquired during conjunction show that the rover is in good health, and that we were therefore "go" for planning. MSL is back in action!

Sol 1030 update by Lauren Edgar: Bumping to Missoula (29 June 2015)

Curiosity is still investigating the contact between the Pahrump and Stimson units. Over the weekend, Curiosity acquired MAHLI images on a coarse-grained rock named “Big Arm” (above). The goal today is to characterize some of the veins that occur above and below the contact, and then bump towards a target named “Missoula” to assess the contact at that location.

The plan today includes ChemCam observations of vein targets named “Lemhi” and “Lowary” corresponding to high and low targets above and below the contact. We will also acquire Mastcam images of the vein targets using all of the camera filters. After a short drive to reposition the rover in front of “Missoula,” we’ll take some Navcam and Mastcam images to prepare for contact science tomorrow. The plan also includes a Navcam cloud movie to monitor the atmosphere. I was the GSTL today and Ken Herkenhoff was the SOWG Chair, so it was a busy day of rover operations here at the USGS!

Sol 1031 update by Lauren Edgar: A Dog’s Eye View at Missoula (30 June 2015)

Today we planned some MAHLI imaging along the contact near the “Missoula” target (the ledge in the upper left portion of this Navcam image). We refer to it as a dog’s eye mosaic, meaning that we use the MAHLI camera to take a series of images along a vertical face – essentially sticking our nose in there to get a good view. Hopefully it will provide a good perspective on the contact between the Stimson and Pahrump units! The plan also includes several ChemCam observations along the contact, at targets named “Selow,” “Clark,” and l'Wapiti.” We planned these as vertical transects to characterize any changes in chemistry from the Pahrump unit into the Stimson unit. We’ll also acquire ChemCam data on the target “Seeley” – a broken rock that exposes a fresh surface. Then we’ll take a Mastcam mosaic to capture the contact and some of the surrounding veins. Ken Herkenhoff and I were both on duty again today, so it was fun planning here at the USGS. We put together a really full plan to handover for Sol 1032, so we’re looking forward to some more exciting contact science tomorrow!

Sol 1032 update by Ryan Anderson: Lots of Contact Science! (1 July 2015)

Phew! Today was a busy day on Mars! Ken and I were both on operations today, picking up where Lauren left off yesterday. Ken was helping with ChemCam science in the geology and mineralogy (GeoMin) theme group, and I was the GeoMin Keeper of the Plan (KOP). We started off the day admiring the beautiful images from the sol 1031 “dog’s-eye view” mosaic of the ledge near the target “Missoula”. Then there was a long discussion about where to do our contact science, and in particular where to put APXS for an overnight measurement. In the end, we decided to do a MAHLI mosaic of the target “Clark”, just to the left of the “dog’s eye” mosaic from sol 1031, and then a MAHLI observation of “Lumpry” which will also be the overnight APXS location.

That is followed by some Mastcam, starting with some carefully-timed images of Phobos as it crosses in front of the sun. After that, we are planning “multispectral” Mastcam observations of targets “Coombs”, “Cottonwood”, and “Lowary”. Multispectral means that we take images of the same target through several different color filters to get an idea of what the reflectance spectrum of the rocks looks like. After all that Mastcam we also have a Navcam movie to search for clouds, and a couple of Navcam images to allow more targeted Mastcam tomorrow.

But wait, there’s more! We also scheduled another MAHLI observation of the target “Seeley” which is a rock that was broken by the rover’s wheels. That is followed by ChemCam observations of “Coombs”, “Regis”, and “Spotted Bear” and associated Mastcam documentation images.

That means that once planning for today was done, we were both also involved in working on tomorrow’s plan, which will cover the long holiday weekend. We will both be on duty tomorrow in the same roles, polishing the plan we started today and making sure the rover is busy doing good science over the weekend.

Sol 1033-1036 update by Ryan Anderson: Independence Day Planning! (2 July 2015)

To paraphrase our SOWG chair’s paraphrasing of the Declaration of Independence at the start of today’s SOWG meeting: “When in the course of human events, it becomes necessary to plan a 4 sol plan, we assemble a group of patriots to make that plan. And that’s what we did today!”

Today I was back on duty as KOP and Ken was on duty for ChemCam science. As usual, it was a busy planning day! After much discussion of what to analyze with ChemCam, we decided to do a 3x3 measurement of the target “Snow Bowl” to see if we could hit some large bright grains in the rock there (similar to the ones you can see in the MAHLI image above), as well as a 3x3 observation of the “Lumpry” target that APXS analyzed yesterday. We also had a Mastcam stereo mosaic of some of the nearby layered rocks. We also have some Mastcam observations of the sun, and a Navcam observation watching for clouds.

One of the trickiest things today was deciding how to schedule our Mastcam and ChemCam observations so that no Mastcam images were taken while ChemCam was turned on. (We try to avoid this because it makes things a lot more complicated). The problem was, we wanted to use ChemCam do a “passive” observation of the sky and then we were planning to do a coordinated observation that involves taking Mastcam multispectral images before and after zapping the target “Thunderbolt” with ChemCam. We solved the problem by moving the “before” Mastcam images so that they occur at the same time of day, but on the previous sol. That way we could go straight from the ChemCam sky observation to zapping the rock target without having to do any Mastcam in between. Solving challenges like this to maximize our science return is a lot of what is involved in day-to-day rover planning.

On sol 1035, while we in the U.S. are celebrating Independence Day, the rover will drive back toward where we were on Sol 991 while doing some DAN measurements. Then on sol 1036 the rover will rest and recharge with a day dedicated to routine REMS measurements.

Sols 1037-1038 update by Lauren Edgar: Familiar Terrain (6 July 2015)

Over the weekend holiday plan, Curiosity drove back to our location on Sol 992. Previous DAN and ChemCam data from this site showed some interesting results, so we want to investigate this region in more detail. The front Hazcam image above shows our wheel tracks from the last time we were here, and some of the bright outcrop that we want to study further.

Today’s two-sol plan includes remote sensing, a drive with several DAN active measurements, and post-drive imaging. The pre-drive science block includes ChemCam observations on targets named “Burke,” “Polson,” and “Bonner,” to look for chemical variations in the bright outcrop. We’ll also acquire Mastcam images of those targets, and take a large Mastcam mosaic to evaluate the sedimentary structures and to provide additional context. Then we’ll take a short drive with a few DAN active measurements along the way. After the drive we’ll take our standard post-drive imaging to prepare for targeting in future plans. Today’s plan also includes some ChemCam calibration activities as well as a Mastcam observation of the sun and Navcam imaging for environmental monitoring. It’s nice to be back in some familiar terrain and to have the chance to do even more science here!

Sols 1039-1040 update by Ken Herkenhoff: Livin' on the Edge (8 July 2015)

I'm MAHLI/MARDI uplink lead today, and was ready this morning to plan lots of MAHLI imaging of the bright rocks on the slope the rover first climbed on Sol 991. But the data received after the 5.5-meter drive on Sol 1037 showed that the left front wheel is perched right at the top of a small scarp at the top of the slope. After examining all the data, the rover planners determined that the rover position is not safe for arm activities, as arm motion could cause the front wheels to slip down the slope, putting the arm and its instruments at risk. So all of the contact science activities were removed from the plan, and remote sensing observations added. On Sol 1039, ChemCam and Mastcam will take a look at targets dubbed "Pistol," "Mary," Shepard," and "Dublin Gulch," and Navcam will search for dust devils. Then the rover will drive backward just a bit to get the wheels on solid ground and allow contact science this weekend (planning is currently restricted, so we are planning 2 sols today). On Sol 1038, Mastcam will take pictures of the Sun to look for sunspots on the side of the Sun that can't be seen from Earth now. Because I had little to do in support of MAHLI planning today, I helped a bit in planning the post-drive Navcam mosaics that we'll need to target observations in the next plan.

Sols 1041-1043 update by Ken Herkenhoff: Busy weekend planned (10 July 2015)

The rover bumped back 33 cm on Sol 1039, placing all 6 wheels on firm ground and allowing contact science on the bright rocks near the top of the slope in front of the vehicle. So the weekend plan is a full one, including both contact science and a drive back toward the southwest. First, on Sol 1041, ChemCam will passively (no laser) acquire spectra of the sky and a rock dubbed "Monarch" before firing its laser at "Frog" and "Mosquito." Mastcam will then take pictures of these rock targets as well as "Elk" and "Lamoose." Later that afternoon, the arm will be deployed to take MAHLI images of Lamoose, Mosquito, and the REMS UV sensor, then place the APXS on Lamoose for an overnight integration. The drive, with DAN measurements along the way, is planned for Sol 1042. In addition to the usual post-drive imaging, Mastcam will again look for spots on the "back" side of the Sun. Overnight, SAM will complete a calibration activity. On Sol 1043, ChemCam will take some calibration data, Navcam will search for clouds near the northern horizon, and Mastcam will take another pair of Sun images. Finally, late that night, CheMin will perform its own calibration activity. So the science team is very busy today, with activities planned for every science instrument on the rover!

Sol 1044-1045 update by Ryan Anderson: Finishing the Drive (13 July 2015)

The drive over the weekend stopped a bit early (~17 meters instead of the intended ~25 meters) because the software that the rover uses to monitor its drive progress was being extra cautious. The rover is fine, and in the sol 1044 plan we will keep driving.

Before the drive, ChemCam has observations of targets of varying textures named “Edith”, “Sheffer”, and “Finley”. Mastcam will take some documentation images of the same targets, along with a stereo mosaic of some interesting layered rocks and a complementary 4x3 mosaic of the nearby “Apikuni Mountain” area.

After the drive, we will take routine post-drive images, and then on sol 1045 ChemCam has some calibration measurements and Navcam has some cloud monitoring observations. On both sols, Mastcam will also continue its sun-spot monitoring campaign, and REMS, RAD, and DAN will do their routine measurements.

Meanwhile, many of us on the rover team are eagerly waiting along with the rest of the world to see the results of the historic New Horizons Pluto flyby that is happening right now. The pictures that New Horizons has sent back already are weird and fascinating, and everyone is looking forward to seeing more!

Sols 1046-1047 update by Ken Herkenhoff: Wheel imaging (15 July 2015)

The 8.5-meter Sol 1044 drive completed as planned, leaving the rover in a relatively flat and smooth area that is suitable for imaging of the wheels. Wheel imaging is done periodically to assess wear, and it's time to acquire new data, so the Sol 1046 includes 5 sets of MAHLI, Mastcam, and MARDI images separated by short rover bumps to allow the entire surfaces of the wheels to be viewed.

Today I helped pick targets on a nearby outcrop for ChemCam observations. The team selected a target dubbed "Mustang" near the left side of this image for a 10-spot LIBS raster (plus a Right Mastcam color image), to be acquired before the wheel imaging on Sol 1046. After the wheel imaging is complete, the usual post-drive images will be acquired, along with additional Navcam stereo images of the outcrop and a Mastcam observation of the Sun.

On Sol 1047, Mastcam will acquire a mosaic of the outcrop to the right of the rover, and ChemCam will make some calibration measurements. The Left Navcam will then search for dust devils and, during evening twilight, MARDI will take an image of the ground near the left front wheel.

Sols 1048-1050 update by Ken Herkenhoff: Test drill and drive (17 July 2015)

The Sol 1046 wheel imaging completed nominally, and the rover is a little over 1 meter from its previous location. So the outcrop to the right of the vehicle is still close enough for ChemCam LIBS measurements, and I helped select new targets again today. The Sol 1048 plan includes ChemCam and Mastcam observations of "Pinto," "Palomino," and "Burnt Point" plus a Navcam search for clouds toward the north. Then the arm will be deployed for drill testing and CHIMRA maintenance activities in preparation for the next drill activity. We are interested in sampling the bright rocks east of the rover, but the Elk and Lamoose targets are not suitable for drilling, so on Sol 1049 we plan to drive toward a nearby bright outcrop of what looks like the same material. We're hoping that we will be able to sample that material with the drill. Early on the morning of Sol 1050, Mastcam, Navcam, and ChemCam will observe the Sun and sky to measure the amount of dust in the atmosphere, search for clouds, and look for changes in atmospheric chemistry. Another full weekend plan!

Sols 1051-1054 update by Ken Herkenhoff: Approaching "Lion" (22 July 2015)

After driving just over 20 meters, the rover stopped 4.4 meters short of the Sol 1049 drive goal because the vehicle pitch exceeded the 15-degree limit set by the rover drivers. So another 6.4-meter drive toward the bright outcrop of interest, dubbed "Lion," was planned for Sol 1051. That drive completed successfully, providing a good view of the outcrop. ChemCam and Mastcam observed the sand ripple "Agency" and bedrock target "Mullan" before the Sol 1051 drive. Now that the Lion outcrop is within LIBS range, ChemCam and Mastcam observations of it are planned for Sol 1053, specifically targets named "Sorrel Springs" and "Buckskin." A nearby rock called "Hewolf" will also be observed before the rover drives closer to the Lion outcrop. Hopefully the rover will be in position for contact science on the outcrop this weekend. The Sol 1054 plan is much less complex, with a Navcam search for clouds above the rover and ChemCam calibration activities. The vehicle should be recharged and ready for a busy weekend plan!

Sol 1055-1056 update by Ryan Anderson: Closing in on High-Silica Targets (24 July 2015)

The main priority in today’s plan is to nudge the rover a bit closer to the target “Buckskin”, which is in the area where we have discovered rocks high in silica and hydrogen. But before we do that, ChemCam and Mastcam will observe the targets “Marent”, “Pilcher”, and “Twinkle”, all of which may also have high silica. Navcam will also search for dust devils and do some atmospheric monitoring. On sol 1056, the rover will execute a short ~70 cm drive, followed by standard post-drive imaging to prepare for contact science on some of these interesting rocks next week.

While the Curiosity team was putting together this weekend plan, we were also keeping an eye on the amazing images of Pluto coming down from New Horizons! The solar system is a weird and wonderful place!

Sol 1057-1058 update from Ryan Anderson: Getting Ready to Drill Buckskin (27 July 2015)

The “bump” over the weekend was successful, so we are right where we want to be to attempt drilling at “Buckskin” in the “Lion” area. I was on duty as ChemCam sPUL (science payload uplink lead) today, and it was a fun day to be on duty. Sometimes it can be stressful trying to make sure that all the settings are correct and that the instrument will be safe, but today everything was easy and I got to spend more time on the fun stuff like choosing targets and their names!

The sol 1057 plan starts off with a Mastcam observation of some disturbed soil at the target “Calamity” followed by ChemCam observations of “Blind Gulch”, “Sorrel Springs”, and “Buffalo Basin”. Mastcam also has a 4x5 stereo observation of the Lion area and some “tau” observations of the amount of dust in the atmosphere. Once all that is done, we will brush a spot on “Buckskin”, observe it with MAHLI, and then place APXS on it for an overnight measurement of its composition.

After a busy sol 1057, sol 1058 is pretty calm: it is mostly dedicated to weather monitoring with REMS, plus MARDI will take an image of the ground underneath us.

Sol 1059 update by Ryan Anderson: Drill Testing and Analyzing "Ch-paa-qn" (29 July 2015)

Today the main event is a “mini-start hole”, which is the name for a new type of initial drilling test that we are trying out on the target “Buckskin”. This test will drill a small hole in the rock to help determine whether it is safe to go ahead with the full hole.

In addition to that test, we are planning a detailed study of the target “Ch-paa-qn” which means “shining peak” in the native Salish language of northern Montana. This target is an isolated bright patch on the nearby outcrop, and we want to figure out if it is calcium sulfate like the white veins we see nearby, or if it is something else. The plan includes ChemCam active and passive observations of Ch-paa-qn, along with Mastcam multispectral images.

After that, we have an atmospheric observation, and then some MAHLI and APXS measurements of the mini-start hole and the full drill target.

Sol 1060 update by Lauren Edgar: GO for drilling! (30 July 2015)

It’s another exciting day on Mars! Curiosity is investigating some high-silica targets at an outcrop named “Lion.” The team selected the “Buckskin” target to drill, and we successfully completed a mini drilling test yesterday (shown in the above MAHLI image). That means that today we’re going for the FULL drill hole.

Today’s plan is focused on the drilling activity, and a lot of imaging to document the hole. First we’ll acquire MAHLI images of the intended drill site, then we’ll drill, and then we’ll acquire more MAHLI images after drilling. The plan also includes Navcam imaging of the workspace, and Mastcam imaging of the target and drill bit. In addition to drilling, we’re getting CheMin ready to receive sample in an upcoming plan. Fingers crossed!

Sols 1061-1063 update by Ken Herkenhoff: Sample dropoff to CheMin (31 July 2015)

This morning, the MSL operations team was very happy to see that drilling into Buckskin was successful! The weekend plan therefore has more arm activities, including transferring the sample to the scoop for inspection. But first, the ChemCam RMI will take pictures of the new drill hole and Mastcam will image a potential location for eventually dumping the sample. The sample will be sieved and a portion of the fine-grained material dropped into CheMin for mineralogical analysis overnight on Sols 1061-1062.

In parallel, the APXS will analyze the potential sample dump location for comparison with future measurements of the dump pile. During the afternoon of Sol 1062, the arm will be moved out of the way so that Mastcam and ChemCam can observe the drill hole and tailings, as well as new targets "Diamond Point" and "Summer Hill." Later that day, SAM will perform a standard (monthly) electrical baseline test. On Sol 1063, the Navcam and Mastcams will observe the Sun and sky, and Mastcam will acquire a stereo mosaic of the outcrop to the right of the rover.

Sol 1064 update by Ken Herkenhoff: Dump pre-sieve sample (3 August 2015)

The activities planned for last weekend completed successfully, including sample dropoff to CheMin and analysis of the minerals present. So the Sol 1064 plan includes dumping the portion of the drill sample that has not been sieved and Mastcam, ChemCam, MAHLI, and APXS observations of the dump pile. ChemCam and Mastcam will also observe nearby targets "Martz" and "Mountain Home." MAHLI will image the drill hole, tailings and CheMin inlet at night using its LEDs for illumination. Such nighttime observations require extra power for heating, so I had to pay extra attention to the power modeling as SOWG Chair today. Fortunately, we didn't have to delete any observations to maintain plenty of charge in the batteries, and I'm happy with the plan we will be sending to the rover this evening.

Sol 1065 update by Lauren Edgar: Last Call at Lion (4 August 2015)

It’s been a great couple of weeks at the Lion outcrop, but it’s time to move on. After a successful investigation that included observations by almost every science instrument, we’re getting ready to drive away tomorrow. That means that today (and tomorrow before we drive) is the last call for science observations.

So we put together a full plan for Sol 1066. In the morning we’ll acquire ChemCam on the target “McClure” to look for chemical variations across the outcrop. We’ll also take a Mastcam image of “Calamity,” as part of a change-detection experiment. Then we’ll acquire MAHLI and APXS on the pre-sieve dump pile, with some additional documentation images. “Pre-sieve” refers to the sample material that didn’t make it through the sieve, in other words, the larger size fraction. By dumping it on the ground we can see what the larger size particles look like and whether they have a composition that varies from that of the full mix of particle sizes. After contact science on the dump pile, we’ll use MAHLI to image the belly of the rover to monitor the spacecraft’s health. In the afternoon, we’ll acquire a large Mastcam mosaic to document the outcrop at higher resolution, and we’ll take several ChemCam RMIs to test the RMI autofocus. Ken Herkenhoff and I were both on duty today (as the SOWG Chair and GSTL), so it was a busy day of planning here at the USGS, trying to make sure we could acquire all of the necessary observations before leaving!

Sol 1066 update by Lauren Edgar: Happy 3rd Anniversary on Mars! (5 August 2015)

Tonight marks the third anniversary of Curiosity’s landing in Gale crater. It’s been a great three years, full of a number of important science discoveries. Check out this video and webpage for a summary of some of the top science results so far.

To celebrate starting her 4^th year on Mars, Curiosity is driving away from the Lion outcrop, and back toward the Missoula outcrop. I feel like Curiosity has really grown up in these past couple of years, and she’s acting like a true field geologist – quickly interpreting key science data, and revisiting sites that will improve our understanding of the geologic history here. In today’s plan, Curiosity will make a couple of final observations at Lion before driving away. In the morning we’ll acquire ChemCam and Mastcam on the target “Moiese” to look for chemical variations across the outcrop. Just before driving away, we’ll take one last Mastcam image of the dump pile, using all of the camera filters. Then we’ll drive back towards Missoula, and take some Navcam images to prepare for ChemCam targeting in tomorrow’s plan. Ken Herkenhoff and I were both on duty today (as the SOWG Chair and GSTL), so it was fun to be part of this important milestone on Mars. Keep on roving!

Sol 1067 update by Lauren Edgar: Bumping to Missoula… sound familiar? (6 August 2015)

With a familiar blog title, I report that in today’s plan we’re bumping towards the Missoula outcrop. On Sol 1066 Curiosity drove ~ 25 m back toward Missoula, but we still have a little further to go. However, the science team took advantage of our current position to collect some additional data on the Stimson unit (shown in the above Navcam image).

Today’s plan includes ChemCam and Mastcam observations of the targets “Dixon” and “Doney” to assess the chemistry in different parts of the Stimson unit. We’ll also acquire a Mastcam mosaic to characterize the terrain that DAN sampled. Then Curiosity will perform several environmental monitoring activities, including a ChemCam passive sky observation, a Mastcam tau, and a Navcam cloud movie, to understand the chemistry and opacity of the atmosphere and search for clouds. Curiosity will then drive towards Missoula, and we’ll acquire post-drive imaging to prepare for targeted science over the weekend. The terrain might look the same, but I’m excited by the additional science that we can accomplish here!

Sols 1068-1070 update by Lauren Edgar: Back at Missoula (7 August 2015)

Curiosity had a successful drive of 19 m on Sol 1067, and we are currently back at Missoula for more targeted science. The goal is to perform a detailed study of the Stimson-Pahrump contact, and to determine the relative timing of some of the veins that we’ve observed here.

The three-sol plan is a busy one, with a lot of ChemCam analyses. On Sol 1068 Curiosity will acquire ChemCam LIBS on four different “Missoula” targets (Missoula A, B, C, and D), to understand the chemistry across the contact. We’ll also acquire several Mastcam images to document those targets. On Sol 1070, we’ll acquire a ChemCam passive observation on the target “Coombs” (“passive” means that we don’t fire the laser, we just passively collect the spectrum of the target), and a regular ChemCam LIBS observation on the target “Stenerson.” Throughout the weekend plan, Curiosity will also perform a number of environmental monitoring activities, to assess the opacity of the atmosphere and search for dust devils. After thoroughly investigating this outcrop with ChemCam, we’ll finally resume our drive through Marias Pass on Sol 1070, and take some post-drive imaging to prepare for science next week.

Sols 1071-1072 update by Ryan Anderson: What we've got here is a failure to communicate (11 August 2015)

Unfortunately over the weekend there was an outage at the Deep Space Network, which prevented the plan for the weekend from being sent to Curiosity. So, instead of a busy weekend, Curiosity was in “runout” mode, making routine environmental monitoring measurements and waiting patiently for more instructions. The sol 1071 and 1072 plans are focused primarily on recovering the observations that were lost in the weekend plan, before we drive away.

On sol 1071, ChemCam has a passive observation of “Coombs”, and active (laser-firing) observations of three locations on “Missoula”. Mastcam will take some supporting images, and Navcam has some atmospheric observations. In the sol 1072 plan, ChemCam has active observations of the target “Stenerson” and another location on “Missoula”, and Mastcam will once again take supporting images, plus an observation of the sun. After that, the plan is leave Marias Pass and drive about 35 meters to the southwest.

Sol 1073 update by Ryan Anderson: Drive-Thru Geology (12 August 2015)

The drive on sol 1072 was successful, with a total distance travelled of about 35 meters. For sol 1073, Mastcam will be very busy taking pictures to document the geology in our new location. We are planning a 31x1 mosaic of the outcrop in Marias Pass, plus a 13x3 mosaic of “Mt. Shields” (not to be confused with Mt. Sharp!) and a 10x3 stereo mosaic of “Gunton”. Navcam also has 8 frames of atmospheric observations of the horizon to the north. Once we are done taking pictures, the plan is to drive for another ~40 meters.

After the drive, we will do our normal post-drive imaging so that we can plan activities for tomorrow, plus an “active” measurement with DAN (meaning that the instrument will produce neutrons to help detect hydrogen in the subsurface, rather than relying on natural background neutrons). The plan also includes some early morning Navcam and Mastcam atmospheric observations on sol 1074.

I’m on duty as science Payload Uplink Lead (sPUL) for ChemCam tomorrow, so I’m hoping we will have some time to zap some targets before we continue driving!

Sol 1074 update by Ryan Anderson: Crazy Mountain (13 August 2015)

The 47 meter drive on sol 1073 went exactly as expected, putting us in a good position for the sol 1074 plan. It’s a pretty simple plan today, with time for a single ChemCam observation of a target called “Crazy Mountain”. I got to pick the name for this target (one of my favorite parts of being involved in operations), and it seemed fitting since the target is on a big layered block that is tilted at a crazy angle. Mastcam will take a 3x3 mosaic of this rock, plus a right-eye image of the target “Blodget” and a 20x1 mosaic of the outcrops and mesas to the east, named “Sa-ol-Sooth”. After that, we will drive some more, and do some post-drive imaging so that we can do some targeted observations in the weekend plan.