Sols 869-870: Broken rock

14 January 2015

The "mini-drill" test on the Mojave rock target completed successfully, but MAHLI images taken after the test showed that the rotary-percussive drilling fractured the rock. This was not expected, so the tactical team had to quickly change the Sol 869-870 plan. While we were hoping to drill a deeper hole and acquire a sample of the drill cuttings before the upgrade of the software onboard the rover next week, the rock fragments dislodged by the mini-drill activity provided a rare opportunity to examine freshly-broken surfaces. Field geologists usually carry rock hammers so that they can break rocks and examine the fresh surfaces. On Mars, the drill has served as MSL's rock hammer! So the Sol 869 plan includes ChemCam measurements of the fresh chunk of rock and the bottom of the mini-drill hole, followed by MAHLI close-up images of the dislodged rocks, both during the day and at night (illuminated by the LEDs). On Sol 870, the brush will be used to clean off another potential mini-drill target, dubbed "Funk Valley." MAHLI images of this new target will be taken before and after the brushing, then the drill will be "preloaded" (pushed down) against Funk Valley and a potential full drill target to determine whether the rock is strong enough to safely drill. Finally, MAHLI images will be acquired to see the results of the preload tests and the APXS will be placed on the brushed spot for an overnight integration.

by Ken Herkenhoff

