Curiosity drove ~25 meters back toward the Marker Band from our detour to the Gediz Vallis Ridge and has returned to the rhythmically layered bedrock we observed on Sols 3648-3649. The first time Curiosity encountered these rocks we were unable to analyze them because one of the rover’s wheels was perched on a rock. Now that we are parked safely, we will use a “Touch and Go” approach where Curiosity will have a busy morning collecting images and data before driving ~15 meters to our next location.

On the first sol of this two-sol plan, the rover will characterize the rhythmically layered bedrock at the “Roxinho” target using a suite of instruments including the Dust Removal Tool (DRT), APXS, MAHLI, ChemCam LIBS, and Mastcam Multispectral. Multispectral Mastcam images are also planned at “Niquia” to document bright soil near the rover and at “Jufari” to examine rocks that were broken by the rover wheels. Mastcam stereo images will document the rhythmically layered bedrock at “Sao Jorge” and the structures in the Marker Band at “Uatuma Anaua.” To round out our imaging, ChemCam will use its Remote Micro-Imager (RMI) to take images of the Gediz Vallis ridge in the distance to study the contact between inverted channel deposit and underlying Mt. Sharp Group rocks. The science on Sol 3670 will include ChemCam AEGIS and basic tau observations.

This is a two sol weekend plan, as Saturday is a soliday. On the first sol, we characterize the workspace in front of us and then drive on the second sol to a new workspace. We are now officially on our detour, a short round trip to image and capture geochemistry of the “Gediz Vallis ridge” up on the pediment, before coming back down to the “Marker Band valley” and rejoining the MSAR (Mount Sharp Ascent Route). This detour will allow us to access some of the area we’d planned to visit before getting turned around by the ‘gator-back’ terrain on the Greenheugh pediment. For this part of the campaign, we are prioritizing driving, getting to our destination as fast as we can, but imaging as we go and marking areas of interest for contact science as we come back down. Today’s drive begins our ascent, taking us up a 16 degree slope to a ridge which will give us good views of the terrain ahead.

This drive also brings us closer to the contact with the Marker Band itself, a relatively thin band of material, traceable throughout this area (see accompanying image), but whose composition and origin are unclear. It may be in our workspace or just beyond after the weekend drive, so the end of drive imagery from the weekend plan will be very eagerly awaited. This imagery includes a very large Mastcam mosaic (48 images) along the potential contact with the Marker Band and some bedrock slabs which may be part of the Marker Band.

Before we drive, we first get as much information as possible from this location. The workspace had bedrock and abundant small grey pebbles or nodules, some of which were loose on the bedrock but some of which appeared to be in place. We managed to find a brushable bedrock spot for the first time since leaving the Canaima drill site, which helps APXS characterize the bedrock free of dust and sand. APXS will also analyze a cluster of the pebbles. MAHLI will image both the brushed bedrock (“Catrimani”) and the cluster (“Marari”) targets. A Mastcam multispectral image on Catrimani rounds out that set of observations. ChemCam is using LIBS to analyze a nodular feature (“Cumate”), a layer of more resistant material (“Wai Wai”) and some more typical bedrock (“Au Au” or “Gold Gold” as we nicknamed it). Mastcam will image both ChemCam targets.

Mastcam will also take several larger images of material just beyond the workspace. “Iniquiare” captures a set of large fractures. “Linepenome” is a set of three images centred on a large float block and the sorting of sands around this feature.

We also continue our environmental monitoring. Mastcam is acquiring a pair of tau measurements and a sky survey to monitor dust levels. REMS and DAN will compliment these with their usual cadence of temperature checks (REMS) and routine hydrogen checks (DAN).

The previous plan included some tests of the sample delivery system, including delivery of a single portion to the closed cover of the SAM inlet. The imaging showed a small amount made it, but not as much as we'd hoped. So the team decided to postpone CheMin sample delivery until tomorrow's plan, leaving us even more time for science activities in today's single sol plan for Sol 2067.

The environmental theme group seized the opportunity to take a long 'dust devil search' movie pointed roughly to the northwest, where we currently have a beautiful view back down the slope of Aeolis Mons toward the Bagnold Dunes, and all the way across Gale Crater's floor to the northwest rim (as shown in this Navcam image from Sol 2060). We've just moved past southern spring equinox, which means we're now in the half of the Mars year when global dust storms are observed to begin. However, the increased surface heating as we head for the warmest time of year should also produce a peak in convective activity and hence in dust-filled vortices known as dust devils. We've already seen a lot this Mars year in our location higher up the slope, so we're hoping for a bumper crop in spring and summer! The ENV theme group also added a long 360° dust devil survey and cloud movie as well as the usual REMS and DAN activities.

On the geology side, following our haul of change detection images over the weekend, we continued to look for surface changes on the Duluth drill tailings and on target "Noodle Lake" that has loose material sitting on the bedrock. The purpose of these experiments is to help us figure out the wind direction and its relative strength at this location, which may help to explain some of the sampling issues (e.g. if the sample is being blown away as it drops). ChemCam also made measurements on "Sawtooth Bluff," a gray, thin alteration layer raised above the bedrock surface, repeating measurements made previously on the nearby "Grand Marais" target, and on "Gary," a raised ridge feature, as well as taking two long-distance RMI images of the "Red Cliff" target as part of an engineering test.