Leonard David's INSIDE OUTER SPACE

Chemistry & Camera (ChemCam) Remote Micro-Imager (RMI) photos acquired on Sol 2894 September 26, 2020
Credit: NASA/JPL-Caltech/LANL

NASA’s Curiosity Mars rover is now performing Sol 2896 duties.

Claire Newman, Atmospheric Scientist at Aeolis Research in Pasadena, California, reports that the rover regularly looks at the Martian atmosphere, making use of its Chemistry and Camera (ChemCam) instrument using a “Passive Sky” observation.

“Among other things, this allows us to measure the amount of some trace gases in the atmosphere above us, including water vapor and oxygen,” Newman explains. “Those measurements, now spanning several Mars years, have revealed that oxygen abundances in Gale crater don’t always follow the expected seasonal variation.”

Artist’s impression of the ExoMars 2016 Trace Gas Orbiter at Mars.
Credit: ESA/ATG medialab

Possible explanations are that there may be unexpected local or distant oxygen sources or sinks, or unexpected chemical reactions.

Orbiter flyovers

“Fortunately, the Atmospheric Chemistry Suite (ACS) instrument on the [European Space Agency’s] Trace Gas Orbiter is observing the atmosphere over Gale crater twice this month, giving us an opportunity to do some rare joint observations of oxygen abundance from the surface and from orbit,” Newman adds.

Those ACS measurements will tell Mars researchers how oxygen varies with altitude, down to about 6 miles (10 kilometers) above the surface. If their lowest altitude measurements are very different to what they measure with ChemCam, that might suggest lots of local surface-atmosphere exchange of oxygen is occurring, Newman adds, which would be exciting.

Curiosity Front Hazard Avoidance Camera Right B image taken on Sol 2895, September 27, 2020.
Credit: NASA/JPL-Caltech

Oxygen variations

“We already had one pair of observations back on sol 2880, but a second pair will happen early on sol 2894. We’re hoping that – between these four observations – we’ll be able to understand better the oxygen variations we see,” Newman points out.

Curiosity Mast Camera Left image acquired on Sol 2894, September 26, 2020.
Credit: NASA/JPL-Caltech/MSSS

For Sols 2894-2897 planning, researchers found out that there was an issue with the arm that prevented them from using it recently, so they planned observations that don’t require it.

Curiosity Right B Navigation Camera image acquired on Sol 2895, September 27, 2020.
Credit: NASA/JPL-Caltech

These included three ChemCam LIBS (Laser Induced Breakdown Spectroscopy) targets (“Duachy,” a diagenetic nodule; “Duntulum,” and “Dervaig”), a ChemCam 12×1 Remote Micro-Imager (RMI) of “Housedon Hill” to finish up long-range imaging of the area, a ChemCam doc image of Dervaig, and a multispectral Mastcam image of the Duachy / Duntulum frame.

Survey area

The robot’s Mastcam also looked at a clast survey area, to search for aeolian changes since scientists last looked there on Sol 2878.

Finally, rover planners included measurements of dust and water ice abundances and properties (with Navcam and Mastcam), as well as searches for dust devils and clouds with Navcam.

Also, Newman concluded, the usual Rover Environmental Monitoring Station (REMS) Radiation Assessment Detector (RAD), and Dynamic Albedo of Neutrons (DAN) REMS, DAN, and RAD were planned.

As always, dates of planned rover are subject to change due to a variety of factors related to the Martian environment, communication relays and rover status.