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Sols 3605-3606: To Drill or Not To Drill

This image was taken by MAHLI onboard NASA's Mars rover Curiosity on Sol 3603.
This image was taken by MAHLI onboard NASA's Mars rover Curiosity on Sol 3603.
NASA/JPL-Caltech/MSSS.

The previous attempt to reposition the rover to be safe for additional contact science (possibly including drilling) at this location didn’t quite get us where we wanted to go. The decision was made early to make one more attempt to park the rover where we can safely contact the ground, including collecting data to help decide if we want to drill this rock. I planned this short drive today as the Mobility Rover Planner.

Prior to repositioning, science is taking advantage of still having interesting targets in our workspace. We begin with some targeted science. Targets “Lago Do Lameiros” is a rock with layers perpendicular to those in the adjacent rock. We are taking Mastcam and ChemCam LIBS observations in order to help document the geochemical variability. “Sientro Catrimani” is an interesting region with rocks of different textures. We are taking ChemCam LIBS and multiple Mastcam stereo observations of rocks in Sientro Catrimani to document the changes in color and texture. We are also taking ChemCam RMI and Mastcam stereo of different spots on the Marker Band (a distinctive layer in the distance) to document the variation in thickness. We also do an hour-long atmospheric observation with dust devil surveys and suprahorizon images to look for dust in the atmosphere.

After the targeted science, the arm is put to work. We are extending the observations on the weekend target Tapirapeco (shown in the image) to get greater coverage of the layers along the vertical face. This target is tricky because to approach the nearly-vertical face we need to come in low to the ground. Additionally, because the rover is slightly perched on some rocks today, and we are concerned about slipping off, we don’t want to get too close to the ground where any motion could cause the arm to hit a rock. We ultimately are taking 6 images from about 16cm away from the rock. Since we can’t touch the rock to get a more precise location, we will have some uncertainty in our distance, but the MAHLI camera can account for this with its focus mechanism.

The second sol of the plan includes more targeted science. Early In the morning, we do a pre-dawn Navcam cloud movie. Then later in the morning we begin targeted science. The “Lake Amuku” target is a smooth area of the block (without nodules) on which we did MAHLI imaging today and over the weekend. We are taking ChemCam LIBS and a Mastcam to document the ChemCam on Lake Amuku. We also are taking a Mastcam mosaic of some sand troughs and ridges near the right wheels to examine their geometry and distribution. Lastly we are taking a multispectral Mastcam of a target “Jerry Spring,” which is another layered rock with significant color and texture variability. We also take Navcam images of the rover deck (to monitor the dust accumulation) and some additional dust devil movie images and horizon image.

After the imaging, we are ready to drive. Finding the exact parking spot that would allow us to DRT this rock was very tricky because of the many rocks (some of which are loose). Additionally, since we may want to drill this block, there are even more constraints on our parking attitude to ensure that drilling is safe and that we can move the arm into position to successfully drop-off sample to the CheMin and SAM instruments. Ideally, we would want the rover to just move straight to its left. However, since only the front and rear wheels can steer, driving sideways isn’t something we can do. Instead we are backing up, turning and then driving to get that distance to the left, and then turning back before driving forward again to put the original block back in our workspace. This complicated maneuver is actually driving the wheels about 5.3m with the end result being a move to the rover’s left by about 50cm. It took several iterations and 5 of us working together to ensure the path we chose would achieve the desired result.

After the drive, we take our standard suite of post-drive imaging of the local terrain and the workspace as well as some additional atmospheric observations looking for dust devils and atmospheric dust.

Meanwhile, we will have to wait until the end of the week to collect all the data we need to determine if we are going to drill at this location – which will depend on our parking spot safety as well as how interesting the science observations indicate this rock to be.

Written by Ashley Stroupe, Mission Operations Engineer at NASA's Jet Propulsion Laboratory