Curiosity surveys a mystery under dusty skies

Curiosity surveys a mystery under dusty skies
This 360-degree panorama was taken on Aug. 9 by NASA's Curiosity rover at its location on Vera Rubin Ridge. Credit: NASA/JPL-Caltech/MSSS

After snagging a new rock sample on Aug. 9, NASA's Curiosity rover surveyed its surroundings on Mars, producing a 360-degree panorama of its current location on Vera Rubin Ridge.

The panorama includes umber skies, darkened by a fading global dust storm. It also includes a rare view by the Mast Camera of the rover itself, revealing a thin layer of dust on Curiosity's deck. In the foreground is the rover's most recent drill target, named "Stoer" after a town in Scotland near where important discoveries about early life on Earth were made in lakebed sediments.

The new drill sample delighted Curiosity's science team, because the rover's last two drill attempts were thwarted by unexpectedly hard rocks. Curiosity started using a new drill method earlier this year to work around a mechanical problem. Testing has shown it to be as effective at drilling rocks as the old method, suggesting the hard rocks would have posed a problem no matter which method was used.

There's no way for Curiosity to determine exactly how hard a will be before drilling it, so for this most recent drilling activity, the rover team made an educated guess. An extensive ledge on the ridge was thought to include harder rock, able to stand despite wind erosion; a spot below the ledge was thought more likely to have softer, erodible rocks. That strategy seems to have panned out, but questions still abound as to why Vera Rubin Ridge exists in the first place.

The rover has never encountered a place with so much variation in color and texture, according to Ashwin Vasavada, Curiosity's project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California. JPL leads the Mars Science Laboratory mission that Curiosity is a part of.

Credit: Jet Propulsion Laboratory

"The ridge isn't this monolithic thing—it has two distinct sections, each of which has a variety of colors," Vasavada said. "Some are visible to the eye and even more show up when we look in near-infrared, just beyond what our eyes can see. Some seem related to how hard the rocks are."

The best way to discover why these rocks are so hard is to drill them into a powder for the rover's two internal laboratories. Analyzing them might reveal what's acting as "cement" in the ridge, enabling it to stand despite . Most likely, Vasavada said, groundwater flowing through the ridge in the ancient past had a role in strengthening it, perhaps acting as plumbing to distribute this wind-proofing "cement."

Much of the ridge contains hematite, a mineral that forms in water. There's such a strong hematite signal that it drew the attention of NASA orbiters like a beacon. Could some variation in result in harder rocks? Is there something special in the ridge's red rocks that makes them so unyielding?

For the moment, Vera Rubin Ridge is keeping its secrets to itself.

Two more drilled samples are planned for the ridge in September. After that, Curiosity will drive to its scientific end zone: areas enriched in clay and sulfate minerals higher up Mt. Sharp. That ascent is planned for early October.


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Sep 07, 2018
"The best way to discover why these rocks are so hard is to drill them into a powder for the rover's two internal laboratories. Analyzing them might reveal what's acting as "cement" in the ridge, enabling it to stand despite wind erosion. Most likely, Vasavada said, groundwater flowing through the ridge in the ancient past had a role in strengthening it, perhaps acting as plumbing to distribute this wind-proofing "cement.""

Haematite is the mineral form of Iron Oxide. Haematite is harder than pure iron, but much more brittle.

Sep 09, 2018
"The best way to discover why these rocks are so hard"

Yeah - who cares? The rover has been driving around in circles, wearing out its wheels, for months. The interesting stuff is farther up the mountain. The fossils are up THERE. You can do all the mundane geology you want back here on earth.

Get on with it.

Sep 10, 2018
"The best way to discover why these rocks are so hard"

Yeah - who cares? The rover has been driving around in circles, wearing out its wheels, for months. The interesting stuff is farther up the mountain. The fossils are up THERE. You can do all the mundane geology you want back here on earth.

Get on with it.


Fossils? You actually think that multi-cellular life has ever existed on Mars? I believe its entirely possible that bacteria or the like have and even potentially still exist on Mars, but Prokaryotic is infinitely less complex than the multi-cellar form capable of leaving actual fossils.

Sep 10, 2018
Not me retard.

"In a new paper published in the Journal of Geophysical Research: Planets, Sean McMahon from Yale University and colleagues present a "field guide" for scientists engaged in the search for putative fossils on Mars. The authors believe the best place to look for fossils would be in mudstones rich in silica and iron-bearing clays that formed in the ancient lakes and rivers of Mars. Microbial life could also have been preserved in silica or calcite-rich hot spring deposits—although these have yet to be found on Mars—and possibly in salt rocks."

-And it of course doesnt need to be multicellular.

"Most of us associate fossils on Earth with the hard remains of shellfish or even bones. But because evolution on Mars most likely stopped with microbial, or at least small, organisms, and did not advance to complex life forms, finding the right environmental conditions for preserving soft bodies is a much more challenging problem."

How come you didnt know this?

Sep 10, 2018
I mean, they find them here on earth right?

"Scientists have found fossil evidence of ancient microbial communities that lived 3.5 billion years ago.

"The new fossils, described in the journal Astrobiology, may be among the most ancient fossil life forms ever found.

"This is one of the, or the, oldest fossils ever found. You've got a 3.5-billion-year-old ecosystem," said study co-author Robert Hazen, an earth scientist at the Carnegie Institution for Science in Washington, D.C."

-Right? duuuuh

Sep 10, 2018
Going to need boots on the ground, or one hell of a rover. No way is Curiosity equipped to find microfossils.

Sep 10, 2018
Going to need boots on the ground, or one hell of a rover. No way is Curiosity equipped to find microfossils
If you drop that last quote I posted you will see that it is a sizable mat, easy to identify. Also

"A few stromatolites, or domelike like rock structures built by ancient microbial communities, have been found at the Strelley Pool formation in Australia that may date to about 3.45 billion years ago. Fossil sulfur-eating microbes from about 3.4 billion years ago have also been found there as well. Other fossils from South Africa reveal microbial communities that date to 2.9 billion years ago."

-And yes, we might even find bones or at least shells of some sort.

Those wheels are going fast. The higher up the mountain, the more advanced the potential lifeforms.

Sep 10, 2018
"A few stromatolites, or domelike like rock structures built by ancient microbial communities, have been found at the Strelley Pool formation in Australia that may date to about 3.45 billion years ago. Fossil sulfur-eating microbes from about 3.4 billion years ago have also been found there as well. Other fossils from South Africa reveal microbial communities that date to 2.9 billion years ago."

-And yes, we might even find bones or at least shells of some sort.

Those wheels are going fast. The higher up the mountain, the more advanced the potential lifeforms.


Yes, but it cannot do much with them. As the paper states;

As noted elsewhere in this review, these protocols raise critical questions about purported 3.7-Gyr-old stromatolites and 3.8-Gyr-old filamentous microfossils on Earth (Dodd et al., 2017; Nutman et al., 2016), and about recently hypothesized MISS in Mars surface imagery


Sep 11, 2018
All we need is pics. The following gold rush will be breathtaking.

Sep 11, 2018
All we need is pics. The following gold rush will be breathtaking.


True, and I hope such a thing happens. It won't be definitive though. Given what I've read about the preparation of samples on Earth, including slicing the rock into thin layers, I'd still rather have boots on the ground. Better still might be a sample return mission if we find something that looks very promising.
Remember the hoohaa over ALH-84001?

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