Curiosity Does Drilling U-Turn on Wobbly Mars Rock
This image from the front Hazcam on NASA's Curiosity Mars rover shows the rover's drill in place during a test of whether the rock beneath it, "Bonanza King," would be an acceptable target for drilling to collect a sample. Subsequent analysis showed the rock budged during the Aug. 19, 2014, test.
NASA/JPL-Caltech (edit by Jason Major/LightsInTheDark.com)
NASA's rover Curiosity has begun drilling operations for the third time on Mars. Currently located at a geologically interesting location nicknamed "The Kimberley," the one-ton rover also took the opportunity to photograph itself and the surrounding landscape in some stunning Martian "selfies." In this scene, Curiosity appears to be leaning its "head" -- a suite of instruments including the Chemcam (the laser "eye") and Mastcam cameras -- to the side, capturing the 5 kilometer-high Aeolis Mons (a.k.a. "Mount Sharp") on the horizon. The self portrait has been stitched togetherby Discovery News' Jason Major
from a series of raw photographs (taken on sol 613, April 28, of the mission) by Curiosity's robotic arm-mounted Mars Hand Lens Imager (MAHLI) instrument.
NASA/JPL-Caltech (edit by Doug Ellison/JPL)
In this scene, Curiosity appears to be concentrating hard on a rock of interest -- dubbed "Windjana" by mission scientists after a gorge in Western Australia -- that it has cleaned with its robotic arm-mounted Dust Abrasion Tool. A grey circular patch can be seen on the otherwise rusty rock's surface where the tool has scrubbed away any surface dust ready for analysis and drilling. This beautiful selfie was createdby JPL's Doug Ellison
, after assembling a collection of photos from the rover's Mars Hand Lens Imager (MAHLI) on sol 613 (April 28) of the mission. Curiosity's selfies not only produce some breathtaking scenes, they are also used by mission engineers to keep tabs on the condition of the rover the more time it is exposed to the harsh Martian environment.
Curiosity used its Mastcam to photograph this closeup of its Rock Abrasion Tool. The instrument spins the wire-bristle brush over rock surfaces to remove layers of dust that has accumulated.
After brushing, a grey circle of rock beneath the ruddy Mars dust is exposed for further analysis. In this photo by Curiosity's Mars Hand Lens Imager (MAHLI), the texture of Mars dust is obvious and fine cracks or seams in "Windjana" can be seen. "In the brushed spot, we can see that the rock is fine-grained, its true color is much grayer than the surface dust, and some portions of the rock are harder than others, creating the interesting bumpy textures,"said Melissa Rice
, Curiosity science team member, of the California Institute of Technology, Pasadena. "All of these traits reinforce our interest in drilling here in order understand the chemistry of the fluids that bound these grains together to form the rock."
On April 29, Curiosity used its drill to bore a 2 centimeter hole into Windjana. This is only the third rock Curiosity has drilled into since landing on the red planet on Aug. 5, 2012. The grey color obviously extends deeper into the rock than just on its surface, and the powder created can provide a pristine rock sample for further analysis, helping mission scientists understand how the rock formed and under what environmental conditions.
The first two drilled rocks were located in Yellowknife Bay, approximately 4 kilometers from The Kimberley. Those rocks were determined to be mudstone slabs formed through water action and sediment, providing compelling evidence that the interior of Gale Crater used to play host to a lakebed and may have provided a habitable environment for ancient microbial life. This new drilling operation will provide more clues as to how rock formed in the region, revealing more tantalizing clues as to the past habitability of the red planet.
Despite its name, one Mars rock isn’t about to enrich NASA’s Mars rover Curiosity with a cascade of science.
After a drilling test last week on a Mars rock dubbed “Bonanza King,” Mars Science Laboratory mission managers noticed that the rock was unstable. So to avoid any unnecessary risk to the rover’s robotic arm-mounted drilling tools, further drilling work in the area was canceled.
Previous to the wobbly discovery, Bonanza King was cleaned by Curiosity’s surface abrasion tool, which cleared off a layer of oxidized dust. In the rock is an interesting vein of white material — possibly sulfate salts — but, alas, Curiosity won’t be sampling any of the rock’s hidden secrets.
“We have decided that the rocks under consideration for drilling, based on the tests we did, are not good candidates for drilling,” said Curiosity Project Manager Jim Erickson of NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “Instead of drilling here, we will resume driving toward Mount Sharp.”
The drilling test was carried out by Curiosity’s percussion tool, which acts like a small chisel by making an indentation in the rock’s surface. But during the impacts, the rock moved slightly. With the previous three successful drilling targets, the rocks were part of more extensive outcrops that provided stability. Bonanza King and the other potential targets in Curiosity’s current location are simply too wobbly for a safe drill.
This is only the latest challenge Curiosity has faced during its epic journey to the 3.4 mile (5.5 kilometer) high Aeolis Mons (known as “Mount Sharp”). Earlier this month, the six-wheeled rover began driving through “Hidden Valley” on its way to Bonanza King, but it experienced some wobbliness itself as it tried to trundle over loose sand.
“After further analysis of the sand, Hidden Valley does not appear to be navigable with the desired degree of confidence,” Erickson said. “We will use a route avoiding the worst of the sharp rocks as we drive slightly to the north of Hidden Valley.”
Since landing on Mars in 2012, Curiosity has notched up an impressive 5.5 miles (8.8 kilometers) of hard Mars driving that has taken its toll on the rover’s wheels. However, there’s only another 2 to 3 miles until Curiosity reaches Mount Sharp’s lower slopes, a goal that is just within reach.