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Fraser
2008-Aug-08, 08:50 PM
Images and data from the Mars Reconnaissance Orbiter (MRO) have revealed layers of clay-rich rock that suggests abundant water was once present on Mars. Scientists from the SETI Institute, the Jet Propulsion Laboratory and several universities have been studying data focused on the Mawrth Vallis area on Marsí northern highland region. This is [...]

More... (http://www.universetoday.com/2008/08/08/evidence-for-widespread-water-on-early-mars/)

Paul Scott Anderson
2008-Aug-09, 05:41 AM
Just saw this thread; I had started one yesterday about this, but under Space Exploration. There is one significant detail missing from this report - the study's team leader Janice Bishop had told Space.com that the most interesting layer found was one of reduced (ferrous) iron, which (on Earth) is usually a result microbial activity:

http://www.space.com/scienceastronomy/080807-mars-clay-02.html

There are other possible explanations, but certainly this is worthy of further study? I've seen little or no discussion of this anywhere yet.

Paul

01101001
2008-Aug-09, 05:49 AM
[...] the study's team leader Janice Bishop had told Space.com that the most interesting layer found was one of reduced (ferrous) iron, which (on Earth) is usually a result microbial activity:


Forming deposits of reduced, or ferrous, iron "usually ... takes microorganisms," she said. For instance, microbes on Earth can transform iron from its ferric to its ferrous state.

But the finding doesn't prove that microbes once existed on Mars, as other processes could account for the iron transformation, Bishop cautioned. Organic carbon, perhaps from an impacting comet, could have reduced the iron or some change in water chemistry could also have done the job. Alternatively, the iron could have been deposited and dried too quickly to oxidize. But which of those processes is correct is anybody's guess at this point.

"Right now we have more questions than answers," Bishop said.

Caution is in order.

Paul Scott Anderson
2008-Aug-09, 06:03 AM
Yes, caution is in order. That said, it is a significant detail which deserves follow-up, but other reports I've seen about this today hadn't mentioned it.

Regardless of that though, these extensive and varied clay deposits provide more evidence for previous long-standing and widespread bodies of water on ancient Mars, as noted in the articles and published papers. Exciting stuff.

Paul

01101001
2008-Aug-09, 06:39 AM
Yes, caution is in order. That said, it is a significant detail which deserves follow-up, but other reports I've seen about this today hadn't mentioned it.

The news has Bishop's microorganism quote, probably copies of the Space.com story. The quote is odd-looking though:


Forming deposits of reduced, or ferrous, iron "usually ... takes microorganisms," she said.

The quoted portion is just a fragment, not a whole thought, and has a bad case of ellipsis-rot within. It really has the look of quote-mining. Was the reporter trying to spice up a story, or was Bishop trying to communicate an important idea? What is the context? What does Bishop usually say, on the record, about ferrous iron?


"Right now we have more questions than answers," Bishop said.

Uh, yeah. For sure.

The original Space.com article title appears to be "Clays Shed Light on Water, Suggest Past Mars Microbes" and is now "Clays Shed Light on History of Mars Water and Possibly Life". It looks like they've toned it down. I wonder if Bishop suggested something less suggestive or if an editor, like, sobered up.

So what kind of followup do you think the data deserves?