10 May 2019
We got the go ahead at the start of planning to proceed with dumping the Kilmarie drill fines from the drill bit assembly. Both the SAM and CheMin instruments have completed or are nearing completion of analyses of the pulverized Kilmarie sample and it is now the turn of APXS and MAHLI to analyze the material. As a member of the APXS team and the strategic planner today for our instrument, I was excited to use APXS and to start analyzing the drill fines. We have been waiting patiently to use APXS and MAHLI, because any arm activity is precluded while sample is in the drill bit assembly. The chemical analysis of the dumped material by APXS and eventually ChemCam will be compared with that of the bedrock surface prior to drilling, as well as to the nearby ‘Aberlady’ drill fines, to look for variations in composition with depth and between the two drill holes. Specifically, the APXS-derived chemistry of the dumped material will be used by the CheMin team to refine their mineralogical analysis. The close-up imaging by MAHLI will tell us about the texture and colour of the fines in detail and assist the APXS team in determining exactly where our instrument was placed. MAHLI will also image the drill hole and tailings (powdered rock material surrounding the drill hole) at a 25 cm standoff to assist placement of APXS and closer-up MAHLI imaging in the next plan. Mastcam multispectral imaging and ChemCam passive spectroscopy of the Kilmarie dumped material will aid in further elucidating mineralogy.
Aside from concentrating on the dumped Kilmarie drill fines, the plan included two ChemCam 5×1 active LIBS analyses to further characterize the transition between compositional end-member bedrock types exposed in the area (targets ‘Valtos’ and ‘Wishaw’). A ChemCam experiment was also planned in order to test a new way of protecting ChemCam from being damaged by inadvertently pointing at the sun. The new method allows ChemCam to take advantage of local terrain features to block the sun, allowing the instrument to target more distant features than if it had to stay below an imaginary, level horizon.A Mastcam mosaic will add to images already acquired of a nearby ripple field, where we are planning to conduct a more detailed study in the near future.
Environmental observations included standard background REMS activities to monitor the daily martian weather, RAD to monitor the radiation environment and DAN passive to study the abundance and distribution of subsurface H- and OH-bearing materials. A Navcam suprahorizon movie will look for clouds and optical depth of the atmosphere and a Mastcam tau observation pointed towards the sun will measure atmospheric opacity.
Written by Lucy Thompson, Planetary Geologist at University of New Brunswick