MISSION UPDATES | April 19, 2023

Sols 3805-3806: Two Steps Forward, One Step Back

Written by Lucy Thompson, Planetary Geologist at University of New Brunswick
This image shows the scuffed bedrock and sand in the workspace including the “Pepejoe” target and was taken by Curiosity's Navcam on Sol 3803.

Navcam image showing the scuffed bedrock and sand in the workspace including the “Pepejoe” target. Credits: NASA/JPL-Caltech. Download image ›

To quote our project scientist, Ashwin, it was clear when we assessed our downlink that Curiosity had almost literally taken “two steps forward and one steps back” during the drive in our previous plan. It has been tricky for our intrepid Mars explorer as we have tried to pick our way through this small canyon as we exit marker band valley. There are abundant large blocks that we are trying to avoid and sand patches that are potential slip hazards for the rover. Unluckily, as Curiosity attempted to back up from the previous parking spot before driving forward, we encountered some of these blocks and sand such that the planned drive did not execute any further. An unforeseen bonus of driving backwards is that we had freshly scuffed sand and rock in our workspace. As a geologist, any time I am in the field here on Earth looking at rocks, one of the first things I do is to use my hammer to expose fresh surfaces, which often reveal different colours and textures than on a weathered surface. At Gale crater, the only time we get to investigate a freshly exposed rock surface is when we scuff or break a rock from driving over it, and then it is often behind us, so we are lucky to have the fresh surfaces in our workspace today.

Unfortunately, because of the tricky terrain, Curiosity was not on stable enough ground to safely unstow the arm. As the APXS payload uplink lead today, I was disappointed that we could not get an APXS compositional measurement and close up MAHLI images of the fresh rock, which would require arm movement. Instead, we will utilize ChemCam and Mastcam to investigate the chemistry and textures of the fresh rock and sand in the workspace. “Paramaca” and “Pepejoe” are examples of the freshly exposed/scuffed bedrock, and we will also capture the wheel tracks in the sand with Mastcam. Looking further afield, we are also acquiring Mastcam and ChemCam RMI imaging of a possible channel feature (“Owentiek”) and a large boulder within the Gediz Vallis channel (“Ratunde”) respectively.

Curiosity will hopefully then weave her way through the sand and blocks, taking many steps forward to our next workspace. After the drive has completed MARDI will image the new terrain beneath the rover, and ChemCam will acquire an AEGIS compositional measurement from a bedrock target in the new workspace.

Not to be left out, the environmental science team have also planned a full set of activities to continue monitoring the atmosphere. These include a Mastcam basic tau observation, as well as a Navcam 360 sky survey, line of sight image, large dust devil survey and suprahorizon movie. Standard REMS, DAN and RAD activities round out this plan.