It’s been a month since my last MSL update, so I’m lagging badly; however, mission news coming out of JPL has been a little lax, so I’m not too far behind the times.
Following my last Curiosity report, drilling and sample-gathering in the area dubbed “The Kimberley” has been completed, and the rover is once more on the move, heading west before turning more to the south once more.
The drilling / sampling operation took place on Sol 621 (Monday May 5th, PDT, 2014), with the percussion drill mounted on the rover’s robot arm turret cutting a hole some 6.5 centimetres (2.6 inches) deep and 1.6 cem (0.63 in) across into a flat sandstone slab which had been dubbed “Windjana” shortly after Curiosity arrived in “The Kimberley” at the end of March 2014. The tailings gathered as a part of the drilling operations were delivered to the CHIMRA (Collection and Handling for In-Situ Martian Rock Analysis) system, in preparation for them to be transferred to the rover’s on-board science laboratory. Confirmation that the sample-gathering had been successful came early in the morning (PDT) on Tuesday May 6th.
The drilling operation, the third time Curiosity has gathered samples from inside a Martian rock for analysis, has caused some excitement among the mission team. “The drill tailings from this rock are darker-toned and less red than we saw at the two previous drill sites,” Jim Bell, deputy principal investigator for Curiosity’s Mast Camera (Mastcam) said after the drilling operation. “This suggests that the detailed chemical and mineral analysis that will be coming from Curiosity’s other instruments could reveal different materials than we’ve seen before. We can’t wait to find out!”
Curiosity’s first two drilling operations took place over a year ago in the “Yellowknife Bay” area of Gale Crater, some four kilometres (2.5 miles) north-east of “The Kimberley”. Analysis of those samples, gathered from mudstone yielded evidence that “Yellowknife Bay” had once been a part of an ancient lakebed environment which contained key chemical elements and a chemical energy source that long ago provided conditions favourable for microbial life.
Following their transfer to CHIMRA, the tailings cut from “Windjana” were sifted and graded in readiness for delivery to the ChemMin (Chemical and Mineralogical analysis) and SAM (Sample Analysis at Mars) suites of instruments, located in the body of the rover. The initial sample transfer to both instrument suites was made on May 15th PDT, 2014. and analysis of the samples should be carried out as the rover continues its journey towards the lower slopes of “Mount Sharp”.
Prior to departing “The Kimberley”, Curiosity carried out a final set of science operations. These involved using the turret-mounted MAHLI (Mars Hand Lens Imager) and spectrometer to examine the texture and composition of the cuttings from the sample drill hole in situ. The ChemCam laser was also used to vapourise some of the drill tailings on the surface of “Windjana” and rock from the inside of the sample hole itself, allowing the ChemCam to analyse the chemical composition of the resultant vapours.