Curiosity Mission Updates
Sol 1985: How Hard is a Rock?Written by Roger Wiens on 03.06.2018
NASA's Mars rover Curiosity acquired this image using its Chemistry & Camera (ChemCam) on Sol 1981 Credit: NASA/JPL-Caltech/LANL
Last week when the first Vera Rubin Ridge drill-hole attempts turned out to be too shallow at "Lake Orcadie", discussion in the team turned to the question of, "How hard is that rock? Is there a way to know before starting the drill hole how hard the rock will be, so we can anticipate whether Curiosity's new drill technique will be successful?" It turns out that the rover team has several indicators of rock hardness: a) retention of natural features such as craters, b) the imprints of wheel marks on the rocks, when we see them, c) scratch marks from the DRT brush, and d) laser pits from ChemCam. This turns out to be a lot of data, especially from ChemCam and MAHLI. However, no one has yet made a quantitative study of rock hardness vs. apparent laser pit depth or brush scratches. The problem is that other factors can affect how deep the pit or scratches look in our images, especially including lighting angle and rock texture and color, but also, for the laser, the distance from the rover and the focus quality. Even so, a study to determine apparent laser pit depth or scratch depth vs. hardness may be useful.
About this Blog
These blog updates are provided by self-selected Mars Science Laboratory mission team members who love to share what Curiosity is doing with the public.
Dates of planned rover activities described in these reports are subject to change due to a variety of factors related to the Martian environment, communication relays and rover status.