17 March 2019

Sols 2349-2351: Capturing Deimos!

Posted by Ryan Anderson

The Curiosity Operations team planned a 3-sol plan today, with lots of activities for both the Environmental (ENV) and Geology (GEO) theme groups. Top priority for ENV and Mastcam is to record a rare solar transit by Deimos (the smaller of the two martian moons) on sol 2350. This is similar to a lunar eclipse here on Earth; however, as Deimos is very small (radius of 6 km), it will not block out the Sun but appear as a dark spot on the solar disk. Although Curiosity has recorded 13 transits by Phobos (Mars’ second moon) within the past six years, we have previously only captured one recording of Deimos crossing in front of the Sun, on sol 42.

GEO‘s main geological target today (‘Caledonia’) comprises three separate targets (1 cm apart) across a mixture of sand and pebbles, to help us determine the origin of the rubbly material found across this part of Gale crater. ChemCam will focus on a pebble here, APXS will analyze each of the three spots, and MAHLI will image each spot. Mastcam will take a multi-spectral image of the whole target to aid in interpreting the results. In addition, APXS will analyze a brushed bedrock target (‘Arbuthnott’) and ChemCam will examine some soil (‘Buzzard’) and an area of small pebbles (‘Gardenstown’). Once we have finished investigating the geology of this location, we drive to a block of tilted rock, 12 metres away, called ‘Muir of Ord.’

ENV also continues to measure the abundance and size of particles of water vapor, oxygen, water ice, and dust in the atmosphere (using ChemCam Passive Sky observations) and the optical depth of the atmosphere (Mastcam full tau observations). ENV also planned a ‘zenith’ movie, which looks directly upwards to look at clouds and their direction of motion, and Navcam and Mastcam ‘dust devil’ movies and surveys, to characterize these dust-filled convective vortices, which can give us information about surface heating, convection, and winds near the surface. There are also standard RAD, REMS and DAN activities. Finally, although APXS is normally used for geological observations, this weekend plan sees APXS used for environmental measurements too. As part of a long running experiment to measure argon fluctuations, APXS will analyze atmosphere while facing the sky overnight on sol 2350. Additionally, APXS will be recording mid-afternoon temperatures on sol 2351.

Written by Catherine O’Connell, Planetary Geologist at University of New Brunswick-Cooper