NASA Mars Curiosity rover finds sandstone variations

Sandstone layers with varying resistance to erosion are evident in this Martian scene recorded by the Mast Camera on NASA's Curiosity Mars rover on Feb. 25, 2014, about one-quarter mile (about 400 meters) from a planned waypoint called "the Kimberley." 

Credit: NASA /JPL-Caltech /MSSS

Variations in the stuff that cements grains together in sandstone have shaped the landscape surrounding NASA's Curiosity Mars rover and could be a study topic at the mission's next science waypoint.

On a journey with many months yet to go toward prime destinations on the lower slope of Mount Sharp, Curiosity is approaching a site called "the Kimberley."

Scientists on the team picked this location last year as a likely place to pause for investigation.

Its informal name comes from a northwestern Australia region known as the Kimberley. The Martian site's geological appeal, based on images taken from orbit, is that four types of terrain with different rock textures intersect there.

Ashwin Vasavada

"The orbital images didn't tell us what those rocks are, but now that Curiosity is getting closer, we're seeing a preview," said Curiosity Deputy Project Scientist Ashwin Vasavada of NASA's Jet Propulsion Laboratory, Pasadena, Calif.

"The contrasting textures and durabilities of sandstones in this area are fascinating.

While superficially similar, the rocks likely formed and evolved quite differently from each other."

The rocks that the Curiosity mission has studied most intensively so far are finer-grain mudstone, rather than sandstone.

The rover found evidence for an ancient lakebed environment favorable for microbial life when it analyzed sample powder drilled from mudstone last year in an area called "Yellowknife Bay."

The rover team is eager to inspect sandstone at the planned waypoint, now just 282 feet (86 meters) south of the rover.

The pause for investigations at this site might include time for collecting rock-sample material with the rover's drill, for delivery to the laboratory instruments inside the vehicle.

NASA MARS Rover Curiosity: Sample Too Big for the Sieve

In this image, the scoop on NASA's Curiosity rover shows the larger soil particles that were too big to filter through a sample-processing sieve that is porous only to particles less than 0.006 inches (150 microns) across.

After a full-scoop sample had been vibrated over the sieve, this held-back portion was returned to the scoop to be accessible for inspection by the rover's Mast Camera.

The image is part of the first "decontamination" exercise by the Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA) tool on the end of the rover's arm, which includes the scoop, the sieve and other components.

The decontamination exercise involved scooping some soil, shaking it thoroughly inside the sample-processing chambers to scrub the internal surfaces, putting it through a sieve, dividing it into the appropriate portions and then discarding the sample.

This process will be repeated three times. The rinse-and-discard cycles serve a quality-assurance purpose similar to a common practice in geochemical laboratory analysis on Earth.

This image was taken by Curiosity's right Mast Camera (Mastcam-100) on Oct. 10, 2012, the 64th sol, or Martian day, of operations.

Scientists white-balanced the color in this view to show the Martian scene as it would appear under the lighting conditions we have on Earth.

Image credit: NASA/JPL-Caltech/MSSS

NASA Mars Rover Curiosity: MSL Mast Camera, the Alpha Particle X-Ray Spectrometer (APXS)

In this image taken by Curiosity's Mast Camera, the Alpha Particle X-Ray Spectrometer (APXS) on NASA's Curiosity rover is pictured, with the Martian landscape in the background

Picture: REUTERS/NASA/JPL-Caltech/MSSS

The APXS (Alpha-Particle X-ray Spectrometer) for MSL is an improved version of the APXS that flew successfully on Pathfinder and the Mars Exploration Rovers Spirit and Opportunity.

The MSL APXS takes advantage of a combination of the terrestrial standard methods Particle-Induced X-ray Emission (PIXE) and X-ray Fluorescence (XRF) to determine elemental chemistry. 

It uses curium-244 sources for X-ray spectroscopy to determine the abundance of major elements down to trace elements from sodium to bromine and beyond.