There's nothing like a day of technical difficulties to make you appreciate when it all works! The science team bounced back from yesterday's challenging planning day with a vengeance, planning an amazingly full suite of observations of the rock - and sky! - around us. The 23 m drive on Sol 1673 put Curiosity alongside Murray bedrock blocks that appeared to be capped with a different material, with a darker color and smoother texture relative to the Murray

The two materials, separated by what looked like bright-toned, sulfate vein material, caught the GEO team's eye, leading us to plan multiple observations of these materials. The "Sorrento Harbor" target aimed to capture the transition from the Murray bedrock to the vein material, and the "Bean Point" target investigated a gray patch among the vein material. This gray patch resembled similar gray patches targeted over the last several weeks given their unique textures and chemistries. The AEGIS-targeted ChemCam raster, acquired post-drive on Sol 1673, ended up hitting the darker, smoother capping material, but GEO complemented it with a second target, "Cape Levi", on another patch of this material in front of the rover. The "Chimney Peak" target, a raster across multiple layers of Murray bedrock, rounded out our targeted ChemCam activities.

GEO kept Mastcam similarly busy. We imaged all the ChemCam targets, acquired a mosaic covering the contact between the darker, smoother capping material, the sulfate vein material, and the underlying Murray, and a stereo mosaic of the "Moxie Mountain" outcrop to investigate the dip of the Murray formation at this spot.

ENV scanned the skies of Gale crater with a variety of images and movies to look for clouds and variations in atmospheric properties. DAN acquired a long passive observation, and regular REMS and RAD measurements will extend our environmental monitoring record within Gale.

Given the sand-covered terrain a few meters ahead of the rover, the rover planners kept today's drive fairly conservative - 10-15 m - to give us a better look at possible drive paths for the weekend. They'll drive us up to a nice curb of bedrock for weekend targeted and contact science! The arm unstow after our drive will give our post-drive images with Navcam and Mastcam an unobstructed view of our weekend work (play?) space.

On Tuesday, the science team had a "soliday", a day without planning to allow the time when the science team plans activities on Earth to realign favorably with when the rover is ready to accept and execute those plans. Our network, however, stayed on soliday through Wednesday morning, leaving the science team without access to the tools we use to plan activities! For most of planning, this was the only full image the science team had of the terrain in front of us.

Fortunately, the rover planners at JPL had a bit better luck, gaining access to enough Navcam and Hazcam images to plan a drive so that the rover did not have to spend the sol idle. The RPs were also able to plan drill diagnostics after the drive to keep investigating the state of the drill. JPL kept the science team posted over the phone - the one way we could communicate with one another. In the event the science team was not able to plan targeted observations, we made plans for basic untargeted post-drive observations that would record the terrain around us (systematically-acquired Mastcam and MARDI images, and an autonomously selected ChemCam target) and help us plan science the next sol (Navcam images of the terrain in front of us and to the starboard side of the rover to target ChemCam and Mastcam).

With just ten minutes to spare before the end of our planning window, our friends in the JPL IT department reestablished the network - it takes a village! The GEO and ENV groups *very* quickly added targeted observations to the already-planned untargeted observations. GEO added a Mastcam image of an autonomously selected ChemCam target shot on Sol 1671, and an 8x2 Mastcam mosaic of an outcrop hypothesized to represent a dry-lake period, parts of which were also studied over the last several sols. ENV planned DAN passive and active observations, and regular REMS and RAD measurements. The activities sailed through the rest of planning, the result of a true (science and engineering) team effort to keep Curiosity busy exploring Mars yet another sol!

Today I covered the ChemCam Payload Element Lead (PEL) role for this first Monday after Easter. Normally the ChemCam team starts Mondays with a telephone tag-up as we hand over operations between the French and US portions of the team. We alternate doing ChemCam operations from week to week, and the Monday teleconferences are the switching point where we convey to the incoming team any useful information that happened the previous week. However, as our French colleagues celebrate Easter a little longer than we do (they have Monday off), we skipped the usual phone tag-up, and traded the usual information by e-mail.

Overall, the French part of the ChemCam team has somewhat more of a challenge, as the daytime operations at JPL in California end up being during the evening and nighttime in France. I attended operations in Toulouse one time and I can verify that operations run very late. French law mandates that employers must provide dinners for anyone who must work late. The operations center at CNES is up to standards with gourmet pre-packaged French cuisine, a small perk for having to work at night. Overall, I have a lot of respect for the dedicated late-night team in France (of course, also for the daytime teams in the US).

Meanwhile, back on Mars, Curiosity nailed the 34 meter drive to another rock exposure identified in orbital images. Ever since we observed possible mud cracks at Old Soaker the rover team has been pursuing the idea that Curiosity is exploring strata that represent occasional dry-lake periods. As the rover drives further from the dunes, it is nice to be seeing more and more interesting rocks out the front window. The main activities in the plan that we’re sending up to the rover today include a 9x7 Mastcam mosaic of the rock outcrop "Jellison Cove", MAHLI, APXS, and ChemCam on "Deer Isle", and a second ChemCam analysis of "Calf Island".

Our latest drive put us in position in front of the interesting "Moosehead Lake" outcrop with lots of veins and grey patches: plenty to keep Curiosity busy over the weekend! The Sol 1668 plan starts off with a nice long science block. ChemCam has observations of targets "Sheldrake Island", "Crabtree Neck", "Waukeah Neck", "Morancy Stream" and "Ogden Point". This is followed by a dust devil survey and several Mastcam mosaics. These include one covering Moosehead Lake, a few frames to extend the coverage of the area near the rover, and a big 22 frame mosaic of the outcrop at our next stop. Mastcam will also take a picture of the ChemCam auto-targeted location from after the drive. After that MAHLI will take pictures of the targets "Morancy Stream" and "Sheldrake Island" and then APXS will analyze those two targets.

On Sol 1669, we’ll retract the arm and drive, followed by post-drive imaging and a MARDI observation in the evening. On Sol 1670, there is a short morning block of atmospheric observations and a longer afternoon block containing a Mastcam image of the rover deck, another dust devil observation, and an auto-targeted ChemCam observation. We will wrap up Sol 1670 with some observations of the dust in the atmosphere to compare with the morning.

Speaking of atmospheric observations, let’s do a recap of the environmental science we’ve done this week. Of course Curiosity acquired the usual REMS and DAN measurements as well as Navcam cloud observation movies throughout the week. The pointing direction of the cloud movies was shifted from north-facing to south-facing to avoid the sun. The movies will remain pointed towards the south until just after the southern hemisphere spring equinox in May 2018. As mentioned above, there was a Navcam dust devil survey on Sol 1670, as well as one earlier in the week on sol 1668. Also captured earlier this week in ENV planning was a ChemCam passive sky observation on sol 1665 that had been previously dropped twice from the plan due to the DSN outage two weeks ago and sun safety issues last week. Planning passive sky observations is difficult: they are among the most time consuming and time constrained atmospheric observations. This is because the observation requires ChemCam to take passive spectra of the sky at two different azimuths and ChemCam must avoid the sun’s path as it slews between those locations. This can be difficult near equinoxes when the sun passes directly overhead!

Dates of planned rover activities described in these reports are subject to change due to a variety of factors related to the Martian environment, communication relays and rover status.

The Sol 1664 drive was halted after the rover had driven less than 2 meters because the angle of the left bogie slightly exceeded the suspension limit. Such limits are routinely set based on the results of detailed modeling of the vehicle's response to the terrain, so that unexpected conditions will automatically cause the rover to stop and wait for further instructions. Analysis of the vehicle's orientation this morning showed nothing that concerned the mobility team, so a drive is planned for Sol 1666. Before the drive, ChemCam and Right Mastcam will observe a vein target named "Ingalls Island," a nearby outcrop target dubbed "Yellow Island," and color boundary targets called "Bunker Cove" and "Cromwell Cove." Mastcam will then acquire a multispectral observation of Moosehead Lake, the drive goal. After the drive and usual post-drive imaging, the arm will be unstowed for more drill diagnostic tests and moved out of the way for Navcam and Left Mastcam imaging of the arm workspace, to support planning on Friday. Later that afternoon, Mastcam will measure dust in the atmosphere, Navcam will search for clouds, and AEGIS will acquire a ChemCam observation of an autonomously-selected target.

The Sol 1667 plan starts with Navcam searches for dust devils and clouds above the horizon. In the afternoon, ChemCam will acquire calibration data. The rover will then get some sleep before what could be a busy weekend plan.

Dates of planned rover activities described in these reports are subject to change due to a variety of factors related to the Martian environment, communication relays and rover status.

MSL drove about 24 meters on Sol 1662, and another drive is planned for Sol 1664. Before the drive, lots of targeted remote sensing is planned: ChemCam and Right Mastcam will observe a bright rock named "Peaks Island," an exposure of bedding dubbed "Great Wass Island," a sand ripple called "Baldpate Mountain," and an interesting rock that was selected by AEGIS after the Sol 1662 drive, now named "Chebeague Island." Mastcam will also acquire a stereo mosaic of outcrops toward the south, in the direction of the planned drive.

Planning is restricted this week, so two sols were planned today. Untargeted remote sensing planned for Sol 1665 includes passive (no laser) ChemCam sky observations and two ground LIBS targets selected using the AEGIS software. Navcam will then search for dust devils and clouds before the rover rests in preparation for Wednesday's plan.

Dates of planned rover activities described in these reports are subject to change due to a variety of factors related to the Martian environment, communication relays and rover status.

Our drive away from the "Ogunquit Beach" sand dune location went well, taking us about 35 meters to the southwest and putting us in a good location to continue measuring the composition of the bedrock as we drive up Mt. Sharp. The Sol 1661 plan starts out with a Mastcam mosaic of "Old Speck Mountain" and some Navcam cloud detection observations. ChemCam will then analyze the targets "Blueberry Mountain," "Brewer Mountain," and "Mud Hole" with Mastcam documentation images for each target. I also requested some long distance ChemCam images of a cliff face on Mt. Sharp. I wasn’t able to participate in planning today, so we will see if the instructions I left the uplink team were correct!

Once the remote sensing is done, MAHLI will take some pictures of the targets "Paradise Hill" and "Treasure Island". APXS will then analyze both targets, with an overnight analysis of Treasure Island. On Sol 1662 we will drive again, followed by an autonomously targeted ChemCam observation, and on sol 1663 Curiosity will have a pretty easy day, with some Mastcam atmospheric dust measurements and a MARDI image of the ground beneath the rover.

Throughout this week, the environmental science group has been working to recover the activities that were lost last weekend because of the Deep Space Network outage, such as the morning imaging suite and 15-frame Navcam dust devil movie, while also continuing the normal cadence of monitoring activities. Earlier in the week, a special DAN active measurement was acquired over the sand of "Ogunquit Beach". By turning the rover in place and backing up onto the dune, we placed the field of view of DAN's active neutron experiment, which is centered between the rear two wheels, right on the dune sand. DAN active experiments are performed after each rover position change (usually immediately after a drive), but in this case, the measurement was taken just before the rover departed Ogunquit Beach. In a DAN active measurement, neutrons are fired in all directions by the Pulse Neutron Generator, and some neutrons scattered by the soil under the rover return to the DAN detectors. This measurement will allow DAN to compare the amount of hydrogen measured at Namib Dune around sol 1243 to the conditions at Ogunquit Beach.

Dates of planned rover activities described in these reports are subject to change due to a variety of factors related to the Martian environment, communication relays and rover status.

Curiosity has been carrying out a great investigation at Ogunquit Beach, but we’re still working out some issues related to the drill feed, so the decision was made to drive away in today’s plan. We’re driving away with a cache full of sand, so we can still deliver to CheMin and SAM in a future plan.

I was the Geology Science Theme Lead today, and our plan was focused on picking up a few last observations at Ogunquit Beach before driving away. The plan starts with APXS on undisturbed sand at the target "Pamola," with corresponding MAHLI documentation images. This observation will be helpful to compare to APXS results from the disturbed sand in the wheel scuff. Later in the afternoon, there’s another arm backbone to run some drill diagnostics. Then we’ll acquire several high-priority Mastcam change detection observations, to monitor the movement of sand in a few places, one of which corresponds to a previous Navcam dust devil survey. We’ll also take two stereo mosaics to evaluate ripple wavelength and height. Before we fully drive away, we’ll position the back of the rover over Ogunquit Beach so DAN can take a measurement. Then Curiosity will continue driving to the south. After the drive we’ll take post-drive imaging for targeting, and prepare for the possibility of contact science in the weekend plan. The second sol includes an autonomously selected ChemCam target, and a ChemCam calibration activity. We’ll also take several Mastcam and Navcam images to search for dust devils and monitor the amount of dust in the atmosphere. Even though we’re leaving the dune behind, there’s some interesting outcrop up ahead so I’m excited to
see what the more resistant outcrop might hold!

By Lauren Edgar

--Lauren is a Research Geologist at the USGS Astrogeology Science Center and a member of the MSL science team.

Dates of planned rover activities described in these reports are subject to change due to a variety of factors related to the Martian environment, communication relays and rover status.

Over the weekend there was a problem with the Deep Space Network that we rely on to transmit commands to Curiosity, so the rover didn't receive its instructions and instead went into "runout" mode, where it patiently waits for commands and does some basic environmental monitoring in the meantime. That means today's plan was a "do-over" trying to cram everything from our weekend plan into two sols.

The Sol 1657 plan starts with a busy remote sensing science block. Navcam will take a couple of images of the workspace, then Mastcam will do a large multispectral mosaic of Vera Rubin Ridge and its interesting iron oxides. This is then followed by a multispectral observation of the target "Fivemile Brook" and an image to monitor the rover deck. Mastcam also has the first of several change monitoring observations in the science block. These observations are repeated throughout the day to see if any sand moves. Once Mastcam is done, ChemCam has a couple of passive calibration activities, followed by a long-distance RMI observation of Mt. Sharp that I requested.

Later in the Sol 1657 plan, MAHLI has a couple of documentation images of the scoop location at Ogunquit, and MARDI has a twilight observation of the ground under our wheels. SAM also has an engineering activity.

On Sol 1658, the plan starts off with some morning atmospheric observations using Navcam and Mastcam, as well as the start of another set of Mastcam change detection images. The main targeted science block on Sol 1658 has ChemCam observations of the targets "Kamankeag" and "Hamlik Peak" with accompanying Mastcam images. Navcam also has a dust devil movie and a cloud movie in this science block.

A little bit later in the afternoon, Mastcam will repeat its change detection image and do another couple of observations to measure the dust in the atmosphere. The change detection images will continue on into the evening, and MARDI will also take another image to see what has changed beneath the rover.

by Ryan Anderson

-Ryan is a planetary scientist at the USGS Astrogeology Science Center and a member of the ChemCam team on MSL. Dates of planned rover activities described in these reports are subject to change due to a variety of factors related to the Martian environment, communication relays and rover status.

Today’s three-sol plan starts with MAHLI imaging of the first scoop location (OG1). The first sol also includes Mastcam and MARDI imaging for change detection. The second sol involves a number of remote sensing activities, starting with a long morning imaging suite for environmental monitoring observations. The imaging suites are special observations that include Navcam cloud movies and dust opacity measurements from both Navcam and Mastcam at an early morning time, when the rover is usually asleep and recharging. The sol 1655 imaging suite is a long version which also includes a ChemCam passive sky measurement, which seeks to determine the chemical composition of the air near MSL. All of these measurements are duplicated in the afternoon to check for diurnal variability. Later in the afternoon we’ll also take a large Mastcam mosaic of "Vera Rubin Ridge," for both stereo and multispectral analysis of the prominent ridge at the base of Mt. Sharp. We’ll also acquire a multispectral Mastcam image of the area observed by the Ground Temperature Sensor (GTS) to help with thermal modeling and grain size determination. The plan includes the usual REMS and DAN measurements, and additional REMS observations were added to determine if the REMS GTS is affected by an increase in winds in the afternoon. The second sol also includes more Mastcam change detection observations, and a large Navcam 15-frame dust devil movie to attempt to capture movement in individual dust devils and to estimate the amount of dust lifted by a range of vortex sizes. On the third sol, ChemCam will perform some calibration activities and analyze targets "Kamankeag" and "Hamlin Peak" to assess the composition of Murray bedrock and a small ripple. I’ll be on duty next week, so I’m getting
caught up and looking forward to more dune campaign activities.

By Lauren Edgar and Michael Battalio

--Lauren is a Research Geologist at the USGS Astrogeology Science Center and a member of the MSL science team. Michael is a Ph.D. candidate in atmospheric science at Texas A&M, and today’s ENV Science Theme Lead.

Dates of planned rover activities described in these reports are subject to change due to a variety of factors related to the Martian environment, communication relays and rover status.