NASA Images Suggest Water Still Flows on Mars Options

[Gray]

I just read Emily's article (the one that Alex cited above) and I have to say that it's raised some questions in my mind. The evidence cited for the white streaks as being from flowing water were: the light color, the fact that they moved around obstacles and the digitate nature of their terminus. Yet if you look at the image of the dark flows, which are considered to be dry dust flows, you can see two of the same features: a digitate terminus and flow around an obstacle. That leaves only the white color as distiguishing them from the dark, dust streaks. Perhaps the light streaks are just a different type of dry flow (we have seen white dust churned up by Spirit) or perhaps the dark streaks are a different type of aqueous flow.

[ugordan]

Mike Malin addressed that as well. The slopes where these deposits are made are fairly gentle, a dry process would have trouble making it that far - was it 1 mile or so? They did computer simulations showing it's most plausible to be a liquid-driven process, liquids flow much more easily than dry stuff.

[Gray]

Ahh, thanks. I missed that part of the evidence.

[odave]

Wow - my UMSF habit gets interrupted by work and life for a few days and look what I miss

What a great exit for MGS, good to see she "died with her boots on" (if indeed she's dead, of course)

[nprev]

Ahem . . . but we have at least one if not many more examples . . . which proves that life in extemely acidic niches on earth is actually TEEMING with microbes.

Please see this article. If you need more, Steve . . . please let me know.

http://www.sfgate.com/cgi-bin/article.cgi?...MNGBCCCDD21.DTL

I hope that Steve Squires has at least noted recently that extremely acidic environments on earth are not barren of life but do support strong colonies of microorganisms. What this means on Mars should not preclude that life does not exist. To the contrary with regards to the recent images and future images to come:)

Absolutely. Go to any old mining town in the western US like Butte, MT or Lead, SD & you'll find all kinds of hardy little critters enjoying themselves in extraordinarily toxic, acidic environments...

[ElkGroveDan]

Absolutely. Go to any old mining town in the western US like Butte, MT or Lead, SD & you'll find all kinds of hardy little critters enjoying themselves in extraordinarily toxic, acidic environments...

And if you go in the winter, the conditions will be remarkably similar to Mars (with -50F not being uncommon in Butte). There's also a very large crater there.

[Guest_AlexBlackwell_*]

Most of us don't think so.

But I see you haven't visited the Wild, Wild World of Hoffmanland. In that case, you'll need directions.

Make sure you're seated during the tour, though

I was waiting to see how long it would take Nick Hoffmann to weigh in. Not surprisingly, I could have predicted this response.

[gpurcell]

Actually, and I may be wrong about this, my understanding of the current planetary protection plan is that we want to avoid sending missions to these gullies to ensure that they stay in pristine state. I would be very, very uncomfortable having MSL trundle up to one.

[tuvas]

Actually, and I may be wrong about this, my understanding of the current planetary protection plan is that we want to avoid sending missions to these gullies to ensure that they stay in pristine state. I would be very, very uncomfortable having MSL trundle up to one.

My understanding is much the same, what a pity... The really interesting targets, and we can't even send anything there... Oh well, I guess that's life...

[Guest_AlexBlackwell_*]

My understanding is much the same, what a pity... The really interesting targets, and we can't even send anything there... Oh well, I guess that's life...

Both of you may be right; I'll have to go back and re-read the latest PP guidelines for Mars. However, I thought that, for example, MSL-related restrictions were due mainly to possible crash scenarios with an RTG power source. I thought that a "go-to" traverse capability (i.e., landing at a safe distance and then roving to the area of interest) would permit visitation of biologically interesting sites, assuming the lander/rover was subjected to Viking-level sterilization.

[Guest_AlexBlackwell_*]

Spacecraft fleet zeroing in on Martian water reserves
ESA News Release
7 December 2006

[aldo12xu]

I looked at the Planetary Protection Guidelines posted on the MSL Marsoweb site and it states:

"1. Prepare the landing system to meet Viking post-sterilization cleanliness requirements (controlled cleaning and assembly as noted below, followed by a system-level dry heat microbial reduction step in accordance with NPR 8020.12C), with control of recontamination through launch and delivery to Mars:

Under this option no restrictions on landing sites or on horizontal or vertical mobility into martian special regions would be imposed on the MSL mission by my office.

John D. Rummel, Planetary Protection Officer"


From Planetary Protection Constraints, dated Aug. 23, 2005: http://marsoweb.nas.nasa.gov/landingsites/...ationLetter.pdf

http://marsoweb.nas.nasa.gov/landingsites/


So it looks like GoTo sites, like the gullies, would be acceptale

[Guest_AlexBlackwell_*]

I looked at the Planetary Protection Guidelines posted on the MSL Marsoweb site and it states...

Thanks, aldo12xu. You saved me from having to wade through Rummel's paperwork.

[odave]

John D. Rummel, Planetary Protection Officer

That's quite a job title - I mean, think of the conversation at a BBQ: "so John, what do you do?"

[Guest_AlexBlackwell_*]

That's quite a job title

It is, and now, I believe, it belongs to Dr. Catharine Conley, at least on an interim basis.

As I understand it, Rummel was recently named to replace Dr. Carl Pilcher as Senior Scientist for Astrobiology in SMD's Planetary Sciences Division. Pilcher is moving on to become Director of the NASA Astrobiology Institute (NAI).

You should listen to the interview of Rummel (last July) on Planetary Radio. Bob Zubrin still gets under his skin