Curiosity continues her climb up toward the lovely cliff of “Mont Mercou” and what could be the start of the sulfate-rich layers of “Mount Sharp” that the science team has had their eye on since Gale crater was identified as our landing site. Mountain climbing has its risks, though, and we found that Curiosity had suffered a bit of an ankle turn - as much as a rover has ankles - at the end of the Sol 3047 drive. The right middle and rear wheels had turned up on some of the lumpier rocks that dot the current terrain (one of which you can just spy under the right middle wheel in the above image), putting us in a not-quite-stable position to unstow the arm and get APXS and MAHLI close to targets in the workspace. That meant we had to forego APXS today, and were limited to MAHLI imaging of the targets “Valojoulx” and “Marval” with the camera safely 25 cm away from their surfaces. The former represents a flatter part of the bedrock in the workspace, and the latter a lumpier, more resistant part of the bedrock.

The awkward placement of the wheels did not prevent all the non-arm instruments from keeping busy, however! We will assess the spectral character of Marval with both ChemCam passive and Mastcam multispectral observations. We will acquire another ChemCam passive on “Chaleix,” a block that is standing proud among the lower-lying bedrock patches around us, thus revealing a vertical face ripe for observation. That vertical face also made an irresistible target for a small Mastcam stereo mosaic. The dramatic buttes above Mont Mercou will be covered by two ChemCam RMI mosaics.

Right before the rover drivers wiggle our wheels off the troublesome rocks of today’s parking space, Mastcam will acquire a large stereo mosaic of Mont Mercou. Then, for an encore, Mastcam will acquire another stereo mosaic of Mont Mercou a few meters into our drive to our weekend parking spot. The hope is that not only will each individual stereo mosaic give us a better picture of the structure within the cliff, but the mosaics together can be combined into their own stereo view, adding different perspective and detail of the cliff.

Mastcam will image the sky as well as rocks. On both evenings of the plan, Mastcam will image a swath of sky above Mount Sharp to look for clouds. Not to be outdone, Navcam will also image the sky to look for clouds and dust devils multiple times in the plan. RAD and REMS keep steady watch on our environment throughout the plan. DAN will ping the ground in back of the rover before, during and after our drive, keeping steady watch on the state of hydrogen in the subsurface. Here’s hoping Curiosity lands in a slightly less bumpy spot for the weekend!

This two-sol plan includes arm, remote sensing and mobility activities on Sol 3047 and more remote sensing on Sol 3048. To continue the sampling of chemistry and texture of the rubbly bedrock as we traverse across it, APXS will perform a short integration on a bedrock block named "Daglan" before MAHLI acquires 3 images (including stereo from a 5-cm standoff) of the same target. I focused on ChemCam planning today, helping to select and refine targets for passive observations of two types of bedrock at "Siorac en Perigord" and "Siorac de Riberac," plus a 10x3 RMI mosaic of a distant exposure of sulfate-bearing rocks. Mastcam will take a multispectral observation of "Cornille," the boundary between the two rock types, and stereo mosaics across similar, nearby transitions. Mastcam will also acquire a stereo mosaic of outcrops to the south that we plan to visit soon, to provide context for future observations. The Right Mastcam will also image "Ajat," a nearby rock face that is just visible over the rover, before Navcam searches for dust devils and clouds. Then the rover will drive toward the southeast and acquire images from its new location to prepare for contact science in the next plan. Finally, MARDI will take another twilight image before the rover rests overnight.

The Sol 3044 drive brought MSL to an area mostly covered by dark sand, with very few exposed rocks in the arm workspace. So one of the first things I did this morning as MAHLI/MARDI uplink lead was to search for good locations for contact science. Unfortunately, none of the rocks that the arm can reach are large enough to be brushed by the DRT, but they don't look too dust-covered so we decided to plan MAHLI images and APXS integrations on two of them, "Pazayac" and "Sadillac" (visible below and right of center in the image above). But first, Navcam will search for clouds and dust devils, ChemCam will acquire RMI mosaics of a nearby rock named "Sourzac" and distant sulfate-bearing outcrops, and Mastcam will take an image of Sourzac and stereo mosaics of nearby sedimentary textures and distant periodic ridges. After the two MAHLI full suites, APXS will be placed on Sadillac for an evening integration, then on Pazayac for an overnight integration.

On Sol 3045, the arm will be moved out of the way for ChemCam passive rasters on a rock dubbed "Saussignac," on Pazayac, and on a soil target named "Sableronne." Then Mastcam will acquire multispectral observations of Saussignac and the contact science targets before the rover drives about 90 meters toward the east-southeast. After sunset, Mastcam will perform a twilight survey of the sky and MARDI will take another twilight image. The vehicle will get some well-earned rest on the third sol, with only a few atmospheric observations by Mastcam, Navcam and REMS. Finally, early on Sol 3047, Navcam will again search for clouds and image the rover deck, and Mastcam will measure the amount of dust in the atmosphere.

Curiosity presses on to the east within Gale Crater, characterizing compositional variations within the underlying bedrock as we continue to march uphill and encounter sedimentary rocks that record the ancient geologic and environmental conditions within the crater. Over the past 35 sols, Curiosity has covered more than 600 meters of lateral distance as we approach these unique compositional transitions observed from orbit. The science team is continuing to make detailed analyses of the regional bedrock to make sure that we understand these transitions from the ground as well.

In today’s plan, Curiosity will be conducting a touch-and-go APXS chemistry analysis on the bedrock target "Manzac" located in front of the rover. She will also be acquiring high-resolution images of the path ahead to aid with future planning, making a suite of environmental observations, and collecting ChemCam passive spectral data on another interesting bedrock unit in front of the rover named “Tranchecouyere." One additional observation will be acquiring high-resolution color images of the target “Tourtoirac," located behind the back-right wheel of Curiosity. This target was a victim to Curiosity’s recent drive, which resulted in this rather large rock tilting onto its side under the pressure of Curiosity’s wheels. It now sticks up at approximately a 45° angle, which will allow scientists to get a good look at whether there are any well-preserved layers or morphologies that are present along the side of the rock. It’s a great bonus observation that might not have been possible had Curiosity driven a few inches in a different direction!

Eleven (Curiosity, Perseverance, InSight, Odyssey, Mars Reconnaissance Orbiter, MAVEN, Mars Express, the Trace Gas Orbiter, the Mars Orbiter mission, Tianwen-1, and Hope) spacecraft are now concurrently exploring Mars from the surface and orbit. That incredible fleet produces synergistic science discoveries that would not be possible with any one spacecraft in isolation. In today’s plan, we will conduct one such joint observation with the Trace Gas Orbiter (TGO). TGO studies the chemical composition of the martian atmosphere as we do with ChemCam through a “passive sky” observation. In a passive sky observation, ChemCam looks at the sky at different angles and positions and we are able to learn about the properties of dust, water ice clouds, and measure abundances of atmospheric gases like oxygen. By combining our work with TGO, we can measure the abundance of such gases from the surface all the way up to the top of the atmosphere!

Outside of this atmospheric observation, today’s plan was a routine touch-and-go. We picked a representative piece of bedrock in the workspace (“Plazac”) for MAHLI and APXS to study and then focused much of our remote sensing science on a fascinating ~18 ft tall cliff (“Mont Mercou”) that can be seen at the top left of this Navcam image. Both Mastcam and ChemCam will image Mont Mercou today and we are driving toward it over the next several plans.

Congratulations to Perseverance and the whole Mars 2020 team! An amazing achievement at any time but even more so during a global pandemic. I don’t think there was a dry eye yesterday, viewing that first image from Mars (shown above) after the incredible nail biting descent. We are all looking forward to the amazing science that will be done by our sister rover in Jezero Crater!

But while everyone is still on a euphoric high from yesterday’s success and the knowledge that we again have two working rovers on the planet’s surface, we had to buckle down and get back to work in Gale today. Our plan today was complex, with many different activities for both the geology (GEO) and environmental (ENV) theme groups. We are continuing our drive across a rubbly, fractured terrain, analyzing bedrock as we go. APXS, MAHLI, ChemCam and Mastcam are tag teaming on a representative bedrock target (“Chalus”) in today’s workspace to maximize our understanding of this rubbly, fractured bedrock. Additionally, ChemCam is doing a series of passive (non-laser) observations on “Carlux,” “Carsac” and “Castels” – a tongue twisting group of names! These observations will be accompanied by Mastcam observations of the same targets, and of a fifth target “Issac” near the front of the rover.

Our drive on sol 3038 takes us almost 45 metres closer to a hill called “Mont Mercou,” which is about 200 metres away from us right now, and the beginning of what we believe to be more sulfate-rich materials. For over 3000 sols (roughly eight years), we have been driving over fluvio-lacustrine sediments (typically found in rivers and lakes), with occasional forays into sand dunes (ancient and current). However, we have been eyeing this potentially sulfate-rich material for years, watching it get closer and closer. The transition from clay-rich to sulfate-rich is both puzzling and extremely important, and one we are looking forward to getting into!

It is truly hard to believe it has been over 8 years - more than 3000 sols - since Curiosity landed in Gale. Most of the science team was crammed into one room at JPL to watch the landing events and (hopefully) celebrate together. When I think back to JPL’s Al Chen declaring “Touchdown confirmed, we’re safe on Mars!” - lo these many years later - I still burst into tears. The feeling of unadulterated joy and disbelief never leaves. I will never forget the raucous explosion in that room - friends and colleagues united in joy and excited for the opportunity to explore Gale crater. Everything we have done since - every image, every measurement, every meter we climb up Mt. Sharp - was enabled by that safe landing. A safe landing on Mars is a gift that keeps on giving, a gift our whole team is grateful for.

Curiosity did her best to honor that gift in this plan, gathering as much as knowledge as she could at this stop before driving on. Mastcam and ChemCam will take mosaics that capture the character of the terrain around us - an intimate mix of sand and bedrock - and the stunning layered buttes that await us farther up Mount Sharp. They will also survey the surrounding bedrock using their multispectral modes that use reflected light to probe mineralogy. MAHLI and APXS will further build our knowledge of the terrain we are on with imaging and chemical analysis of a target that is a mix of sand and rock. Navcam and Mastcam will gaze up into the atmosphere that Curiosity passed through to safely reach the surface, each measurement they make contributing to safer, surer landings in the future. And REMS, RAD, and DAN will make measurements that will make it safer for humans to make the trip to Mars.

Tomorrow, if all goes well, a new team poised for a new set of adventures will get to feel the same joy and excitement we did in August 2012. The Navcam image above looks toward the direction of Perseverance’s landing site in Jezero crater. Curiosity wishes Perseverance a safe last leg of her journey, the opening of a new gift of exploration.

Curiosity is staying put in today's plan and feasting on some bonus science. Our goal remains to traverse away from the rocks we have determined are clay-rich and toward the overlying sulfate-rich rocks uphill. But for the current plan, the team decided to stay at this location a little longer and get a better taste of what the rocks here have to offer before executing a longer drive toward the sulfate strata in the following plan.

Our appetizers include standard activities for DAN, REMS, and RAD as well as Navcam and Mastcam monitoring of the atmosphere and dust devils. Our science buffet includes ChemCam and Mastcam images of targets "Beauregard" and "Sorges," which have interesting dark inclusion features that have been seen recently and these observations will help the team understand them better. (We don't expect these to be chocolate chips, but better to get good images to be sure...) Mastcam is also imaging the bedrock target "Labraud" and sand target "Fleurac." MAHLI and APXS are hungry for science as well, so we will get MAHLI images and APXS analysis of the brushed target "Limeyrat," a perfect target for dessert. Yum!

Curiosity is on the final approach to the base of the sulfate-bearing unit identified from orbit as a region of interest within Gale crater long before we landed. The base of the unit marks a change from the underlying clay-bearing strata (rock layers) that Curiosity has been investigating for the last two years. Clay minerals are typically associated with wetter environmental conditions and sulfate minerals with drier conditions, so the contact between the two may represent a significant change in environment. It is therefore important that we carefully document the rocks for texture, structure and composition as we transition from the clay-bearing to sulfate-bearing unit, looking for gradual or abrupt changes that may help to elucidate what happened at this boundary.

Curiosity will first unstow her arm and place the APXS on the rock target “Firbeix” for a short analysis to determine the chemistry of the representative bedrock, before taking close-up images with MAHLI. As the APXS payload uplink lead today, I am responsible for overseeing the planning of the APXS measurement. After stowing the arm, the ChemCam instrument will take a passive spectroscopic observation of the “Feiullade” bedrock target, and RMI observations of another bedrock target “Fraisse” and the basal layers of the sulfate-bearing unit ahead. We will also image the Firbeix, Feiullade and Fraisse targets with Mastcam, and look at some sand cracks and the fractured terrain ahead with Mastcam mosaics. Curiosity will then drive carefully over this blocky terrain for a planned distance of ~35 meters. After the drive has executed, a MARDI image will be taken to capture the terrain beneath the two front wheels.

The second sol of this two-sol plan is dominated by environmental observations to monitor the atmosphere including a ChemCam passive sky observation, a Mastcam basic tau pointed towards the sun, a Navcam suprahorizon movie, dust devil survey and line of sight image. Standard REMS, RAD, DAN passive and active measurements will also be acquired.

Curiosity and everyone on the MSL team would also like to welcome Tianwen-1 to Mars. Congratulations to the Chinese space agency for a successful insertion into Mars orbit. It is an exciting time for Mars missions and science.

This past weekend, Curiosity celebrated the start of a new year on Mars. The concept of a martian year is similar to an Earth year, mainly that it marks the time it takes Mars to go around the sun once. A key difference is that a martian year is 668 sols long, or about 687 Earth days. We count Mars years starting with a big dust event that occurred in 1956 that marked Mars Year 1, so Curiosity just rang in the start of Mars Year 36 at Gale Crater. There weren’t fireworks or a crystal ball drop like in Times Square, but it’s still fun to think about the way time is measured on other planets.

In today’s plan, Curiosity is continuing along its journey through the rubbly unit that marks the transition from the clay-bearing rocks of "Glen Torridon" to the salty sulfate-bearing strata ahead. We planned a MAHLI and APXS observation on a piece of bedrock on our workspace named “Brantôme,” Mastcam multispectral observations, and some Mastcam and ChemCam RMI mosaics of a small crater named “Rouchechuart” and distant strata we named “Riberac.” After these science observations, Curiosity will drive ~39 meters towards the sulfate-bearing unit, which we can see forming dramatic and inviting cliffs in the distance, as shown above.

At the beginning of our planning day Curiosity team members also celebrated the arrival of a brand new orbital neighbor, the Emirates Mars Mission “Hope Probe.” Hope is the first mission to Mars led by the United Arab Emirates Space Agency, and its arrival into Mars orbit this morning represents an extraordinary accomplishment. Welcome to Mars, Hope, we’re so excited to have you here!