This composite image looks toward the higher regions of Mount Sharp within Gale Crater, Credit: NASA/JPL-Caltech

This composite image looks toward the higher regions of Mount Sharp within Gale Crater,
Credit: NASA/JPL-Caltech

This composite image looking toward the higher regions of Mount Sharp within Gale Crater was taken on September 9, 2015 by NASA’s Curiosity Mars rover and released by the Jet Propulsion Laboratory (JPL) last week.

In the foreground — about 2 miles (3 kilometers) from the rover — is a long ridge teeming with hematite, an iron oxide. Just beyond is an undulating plain rich in clay minerals. And just beyond in this photo re a multitude of rounded buttes – all high in sulfate minerals.

Further back in the image are striking, light-toned cliffs in rock that may have formed in drier times and now is heavily eroded by winds.

“The changing mineralogy in these layers of Mount Sharp suggests a changing environment in early Mars, though all involve exposure to water billions of years ago,” explains the JPL Curiosity website.

Grey Mars

It may not be 50 shades of grey.

Grey Mars as imaged by Curiosity’s Mastcam Right, snapped on September 30, 2015, Sol 1120. Credit: NASA/JPL-Caltech/MSSS

Grey Mars as imaged by Curiosity’s Mastcam Right, snapped on September 30, 2015, Sol 1120.
Credit: NASA/JPL-Caltech/MSSS

But I asked noted Marsologist, Chris McKay at the NASA Ames Research Center in California about “the greying of Mars” – what’s going on?

“I list the ‘grey Mars’ as one of the four major results of Curiosity – nitrates, fluoride, meteroritic-like organics are the other three,” McKay told Inside Outer Space.

McKay said that virtually all other Mars missions have only accessed the surface of “red Mars.”

Mars stinks!

“The non-porous mudstone at Gale Crater has provided a way to easily reach ‘grey Mars’…even with the rather wimpy drill on Curiosity,” McKay said.

As expected, McKay points out, grey Mars releases Hydrogen sulfide (H2S) when heated and it smells like rotten eggs.

“Unexpectedly it is low in organics — although some are found in Cumberland   and has perchlorate,” McKay notes. “I think this is due to cosmic radiation and implies that we need to drill deeper to find pristine grey Mars – probably 16 feet (5 meters) deep at the Yellowknife Bay site.”

Methane measurement

In related news about the new drill hole and tailings: The weekend plan called for an after dusk use of the Mars Hand Lens Imager (MAHLI). That instrument will make use of its LEDs to look inside of the drill hole and image the drill tailings.

This image was taken by ChemCam: Remote Micro-Imager onboard NASA's Mars rover Curiosity on October 4, 2015, Sol 1123. ChemCam fires a laser and analyzes the elemental composition of vaporized materials from areas smaller than 1 millimeter on the surface of Martian rocks and soils. Credit: NASA/JPL-Caltech/LANL

This image was taken by ChemCam: Remote Micro-Imager onboard NASA’s Mars rover Curiosity on October 4, 2015, Sol 1123.
ChemCam fires a laser and analyzes the elemental composition of vaporized materials from areas smaller than 1 millimeter on the surface of Martian rocks and soils.
Credit: NASA/JPL-Caltech/LANL

That operation is to be followed by use of the Alpha Particle X-Ray Spectrometer (APXS) and placing that device over the tailings for an overnight measurement.

MAHLI is also slated to image the pre-sieve dump pile and APXS will be placed over it for another overnight integration.

The Sample Analysis at Mars (SAM) Instrument Suite is to be used for an atmospheric methane measurement. SAM is being put to use because Mars recently went through the path of comet Damocles.

“Dust ejected from comets is often carbon-rich, and therefore is a possible source of the elevated methane concentration that has occasionally been observed by SAM,” explains Ken Herkenhoff of the USGS Astrogeology Science Center in Flagstaff, Arizona.

Leave a Reply