MISSION UPDATES | September 15, 2023

Sols 3950-3952: Dusty Skies in the Cloudy Season

Written by Conor Hayes, Graduate Student at York University
This image was taken by Left Navigation Camera onboard NASA's Mars rover Curiosity on Sol 3948.

This image was taken by Left Navigation Camera onboard NASA's Mars rover Curiosity on Sol 3948. Credits: NASA/JPL-Caltech. Download image ›

Earth planning date: Friday, September 15, 2023

Some days, the process of preparing a plan to be uplinked to our intrepid rover goes beautifully smoothly, with everyone and everything working together in near-perfect synchrony. Other days, it can feel like the entire universe is conspiring against us. Planning today was definitely one of the latter. Our drive from Wednesday's plan came up about four metres short of the intended destination, meaning that we didn't have the images required to determine whether or not it is safe to unstow the arm over the weekend. Consequently, we had to pivot today's plan to one focused on imaging. This isn't an unusual occurrence; however, there was a small software problem here on the ground that prevented us from accessing the higher-resolution images that we need to select imaging targets until quite late in the planning timeline.

Fortunately, all of the images did eventually arrive, so we didn't have to pull any observations. It's a good thing too, since we are planning quite a few! Here over in the Atmosphere and Environment Science Theme Group (ENV), we're used to our planning days being a little more low-key than those of the Geology and Mineralogy Science Theme Group (GEO). Because the atmosphere is all around us, we can pretty effectively create our plans in advance without having to worry about where we'll end up after driving or what interesting rocks we'll be able to safely touch. We are also always aware of the fact that geology is Curiosity's primary mission, so we try to keep our time requests to the minimum that is necessary to accomplish our own science objectives.

On occasion, we do have to request more time than usual, as we had to today thanks to the confluence of multiple events. First, there has been more dust in the atmosphere than we're used to seeing at this time of year, so we added a "tau" observation, where we take images of the Sun using Mastcam to measure how much dust is in the air, to each sol of the plan in order to track how this excess dust evolves over time. Second, we were due for a "passive sky" observation where we use ChemCam and APXS to measure the composition of the atmosphere. This is one of the longer observations that we have, so it can really limit the amount of science time left over for GEO on a particular sol. Happily, the rover's batteries are nice and charged up, so both ENV and GEO were able to fit in almost all of what we wanted without having to negotiate what should be sacrificed in favour of higher-priority observations. Power can sometimes be challenging during the winter since we need to dedicate more of it to keeping the rover warm, so it is always nice when it cooperates with us.

Our plan today starts off with a couple of ENV activities. In addition to a tau measurement, we also have a 21 frame movie pointed off towards a nearby sand patch to see if we can catch the wind blowing some of the sand around. We then jump into some GEO observations, including Mastcam imaging of "Lodgepole," a layered block with some resistant fin features (which you can see in the cover image above, just left of centre), and a Mastcam mosaic looking towards our potential next drilling location up Gediz Vallis. ChemCam will continue its RMI imaging of the upper Gediz Vallis ridge and will target "Scylla" with LIBS, the results of which will be documented by Mastcam.

The rover then gets to sleep overnight before waking up for another sol of activities, starting off with another Mastcam tau and Navcam cloud movie, as well as Mastcam imaging of some polygonal fractures on the target "Seven Gables." ChemCam LIBS and Mastcam will then once again collaborate on the target "Lupine." We will then drive to our next location before going to sleep again.

When we wake up, we will once again begin the sol with a Mastcam tau and a Navcam 360 degree survey for wind-induced dust activity around us. Because we don't know exactly where we'll end up post-drive, we can't select another LIBS target ourselves, so we'll let the rover do that itself. The final big activity for the third sol of this plan is the aforementioned ChemCam passive sky for ENV.

As is always the case with weekend plans, we wrap up with some early morning ENV activities right before we hand over into Monday's plan. These include a Navcam Phase Function Sky Survey, which takes nine three-frame movies forming a dome around the rover to look at clouds across the entire sky, two eight frame cloud movies looking directly overhead and just over the horizon, another Mastcam tau, and Mastcam and Navcam images of the north crater rim.

Of course, we can't neglect to mention the hard work of REMS, RAD, and DAN, all diligently taking their routine measurements as we enjoy the weekend.