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Signs of Liquid Water Found on Surface of Mars, Study Says

nytimes.com

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Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#161

Post by duncan_bayne »

bglazer wrote: post #158
Havoc wrote: post #153

Earlier quoted context omitted.

What is the real contamination risk though? Suppose some biological particle makes it to mars. Then we pick it up, discover that its very dead already, DNA sequence it and find that it matches the common flu. Write it off as contamination, rinse & repeat until we find something that is alive & looks like green men. Or can science genuinely not distinguish earth contaminants vs alien life?

One possibility, perhaps very unlikely and perhaps somewhat likely, is that Earth life could actually survive and adapt to Martian conditions and subsequently destroy existing Martian life. That seems almost comically improbable, but given that we've found that lichen can survive in the vacuum of space for a year and a half [1] and the mere existence of life on hydrothermal vents and inside Chernobyl[2], I think we c…

So, if we accidentally terraform a planet with only microbial life, what's the downside?

The only loss I can see is the lost opportunity to study a truly alien ecosystem in detail, but if we can't study it without fatally contaminating it, that was never really a benefit we could enjoy anyway.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#162

Post by mturmon »

mirajshah wrote: post #138
crusso wrote: post #12

R.S.L.s are treated as special regions that NASA’s current robotic explorers are barred from because the rovers were not thoroughly sterilized We're not going to sterilize our research equipment going to Mars and we're not going to search likely sites where we could find life because we don't want to contaminate them. And yet, looking for signs of life native to Mars (or even water which might support life) is the to…

The amount of armchair condescension on HN is appalling. According to the reddit AMA, NASA does do some amount of sterilization before going to Mars, it is enough to justify the exploratory mission. More sterilization would probably take more man hours, more $$$, which would delay the mission to account for an (estimated) low probability of finding water. It seems like they've chosen to iterate instead of getting it…

"The amount of armchair condescension on HN is appalling."

So true. It's surprising that some commenters, above and nearby, don't stop to think that a decades-long, multibillion-dollar exploration program, with dedicated conferences (e.g., http://www.hou.usra.edu/meetings/lpsc2015/), journals (e.g., http://agupubs.onlinelibrary.wiley.com/agu/jgr/journal/10.10... or http://www.journals.elsevier.com/icarus/) and scientific communities in the many hundreds of scientists, professors, postdocs, and PhD's, has not gone deeper than sophomoric gotchas like in the comment above.

I admit, there is a question here about exploration strategy. The question is how to approach it -- and a little humility and willingness to poke around for information would be in order.

Edited to add: The root for documents pertaining to Mars exploration strategy is here (http://mepag.nasa.gov/reports.cfm) and an excellent reference for contamination control for the upcoming Mars-2020 rover is here (http://mepag.nasa.gov/reports/OCP_2014_final_report_docx.pdf).

Finally, don't miss this deep analysis of the "Special Regions" on Mars (http://mepag.nasa.gov/reports/Rummel_et_al_Astrobiology_14-S...). From the abstract:

"Significant changes in our knowledge of the capabilities of terrestrial organisms and the existence of possibly habitable martian environments have led to a new appreciation of where Mars Special Regions may be identified and protected. The SR-SAG also considered the impact of Special Regions on potential future human missions to Mars, both as locations of potential resources and as places that should not be inadvertently contaminated by human activity."

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#163

Post by coldtea »

semi-extrinsic wrote: post #154
trose wrote: post #114

Earlier quoted context omitted.

I'm kinda of this thought process as well. If there are hospitable conditions there and we haven't found microbes after a while, I think we should just start dumping tons of them over there. We need something to put some atmosphere there for us. Algae seems to be a really good bet.

In that scenario you're saying that the Martian landscape itself is not worthy of preservation, while any microorganisms could be. Both amoeba and rocks have no claim to consciousness etc., so why is one worthy of preservation while the other is not?

OP is not interested in preservation for preservation's sake.

It's not like we should care about the consciousness of microbes. What he meant, as I read it, is that if there are microbes we'll want to sample them and study them BEFORE we change the landscape and possible kill them.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#164

Post by coldtea »

ypcx wrote: post #149
ypcx wrote: post #116

Earlier quoted context omitted.

What would you do if you wanted to postpone, as long as you possibly can, the disclosure of discovery of life on Mars? Exactly. Ridiculous question, of course, how do I even dare to have a thought like that here on HN, the bastion of reason. Unless there are reasons to suppress everything that would somehow threaten the status quo. Pause for a second and ponder the inexplicable urge to downvote this comment, which is…

You have to question the motives of an agency which needs half a century of spaceflight and trillions of dollars to admit water on a nearby planet.

Yeah, it's like they are doing ...science.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#165

Post by crusso »

InclinedPlane wrote: post #157
crusso wrote: post #143

Earlier quoted context omitted.

Please don't invent hostile motives in my post when none were being offered. I was simply pointing out the impasse expressed in the article. This isn't NASA's internal blog of scientists, so I'd think that possibly dumb speculation could be offered. The iteration explanation makes some sense, although these seem like very expensive iterations.

You are literally strolling into a subject you know nothing about and putting forward an opinion that amounts to "wow, these guys sure are dumb, huh?" It's a very common way to comment on science stories and it's absolutely infuriating. Why not this? "So, I don't understand what's going on here, this seems weird because of X, Y, or Z, can someone explain what's going on?" Or this? "Is NASA really so dumb that they wo…

Except I didn't say any of the versions of what you paraphrased. I didn't say anyone was dumb. I didn't say "Hah". None of it.

Why are people so heavily invested in maintaining their own ignorance?

More attacks. Why? Look, I took a 10 minute break to read some HN this morning and read the article. I didn't know all the details and I had to get back to work, so just threw out a speculation. Judging from the 35+ upvotes I received, it was something many others reading the article were curious about.

Why do people insist on jumping to the conclusion that thousands of top tier scientists couldn't POSSIBLY have thought of the same things that occurred to them in the few moments spent thinking about it before deciding to make a post?

I guess you could wonder why you jumped to the conclusion of my thought process because you were wrong. NASA isn't just scientists. Often decisions are made for political, bureaucratic, and budgetary reasons that have nothing to do with the science. Sometimes, smart people do lame bone-headed things.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#166

Post by coldtea »

kenbellows wrote: post #43
nsxwolf wrote: post #42

Earlier quoted context omitted.

Not a new discovery in itself, either.

yes it is...?

You haven't been following these news very closely, do you?

2008: NASA Spacecraft Confirms Martian Water, Mission Extended http://www.nasa.gov/home/hqnews/2008/jul/HQ_08_195_Phoenix_w...

2009: Meteorite Impacts Expose Ice on Mars http://science.nasa.gov/science-news/science-at-nasa/2009/24...

2010: NASA Trapped Mars Rover Finds Evidence of Subsurface Water http://www.jpl.nasa.gov/news/news.php?release=2010-355

2011: Observations from NASA's Mars Reconnaissance Orbiter have revealed possible flowing water during the warmest months on Mars. http://science.nasa.gov/science-news/science-at-nasa/2011/04...

2013: Curiosity's SAM Instrument Finds Water and More in Surface Sample http://www.nasa.gov/content/goddard/curiositys-sam-instrumen...

2014: New Evidence for a Mars Water Reservoir http://science.nasa.gov/science-news/science-at-nasa/2014/19...

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#167

Post by mehwoot »

duncan_bayne wrote: post #161
bglazer wrote: post #158

Earlier quoted context omitted.

One possibility, perhaps very unlikely and perhaps somewhat likely, is that Earth life could actually survive and adapt to Martian conditions and subsequently destroy existing Martian life. That seems almost comically improbable, but given that we've found that lichen can survive in the vacuum of space for a year and a half [1] and the mere existence of life on hydrothermal vents and inside Chernobyl[2], I think we c…

So, if we accidentally terraform a planet with only microbial life, what's the downside? The only loss I can see is the lost opportunity to study a truly alien ecosystem in detail, but if we can't study it without fatally contaminating it, that was never really a benefit we could enjoy anyway.

I doubt that the level of life succeeding enough to damage our ability to determine if there was already life there is on the same order as "terraforming a planet". I doubt there would be much upside.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#168

Post by duncan_bayne »

mehwoot wrote: post #167
duncan_bayne wrote: post #161

Earlier quoted context omitted.

So, if we accidentally terraform a planet with only microbial life, what's the downside? The only loss I can see is the lost opportunity to study a truly alien ecosystem in detail, but if we can't study it without fatally contaminating it, that was never really a benefit we could enjoy anyway.

I doubt that the level of life succeeding enough to damage our ability to determine if there was already life there is on the same order as "terraforming a planet". I doubt there would be much upside.

Sure - by 'terraforming' I just meant 'replacing Martian life with Earth life'; terraforming from the microorganisms perspective perhaps, not from the perspective of humans. There's a lot of work involved in that, way beyond our current engineering capacity.

I'll make my thinking more explicit ...

The best case is that we either a) don't introduce microbial life, or b) it just flat-out dies. Then we can examine Mars for signs of life (current or historical).

The worst case is that we contaminate Mars with microbes that flourish there, forever destroying our ability to examine Mars for signs of life.

I'm assuming we can't explore Mars without risking the worst case. So it seems worthwhile to try; the very worst case is that we replace a Martian microbial ecosystem with one from Earth.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#169

Post by mehwoot »

coldtea wrote: post #166
kenbellows wrote: post #43

Earlier quoted context omitted.

yes it is...?

You haven't been following these news very closely, do you? 2008: NASA Spacecraft Confirms Martian Water, Mission Extended http://www.nasa.gov/home/hqnews/2008/jul/HQ_08_195_Phoenix_w... 2009: Meteorite Impacts Expose Ice on Mars http://science.nasa.gov/science-news/science-at-nasa/2009/24... 2010: NASA Trapped Mars Rover Finds Evidence of Subsurface Water http://www.jpl.nasa.gov/news/news.php?release=2010-355 2011:…

First three links and fifth are all talking about ice, not liquid flowing water.

Fourth link isn't conclusive

These results are the closest scientists have come to finding evidence of liquid water on the planet's surface today.

The last link summarises that liquid water has not been conclusively found yet, and it is the most recent:

While recent orbiter missions have confirmed the presence of subsurface ice, and melting ground-ice is believed to have formed some geomorphologic features on Mars, this study used meteorites of different ages to show that significant ground water-ice may have existed relatively intact over time.

Curiosity’s observations in a lakebed, in an area called Mount Sharp, indicate Mars lost its water in a gradual process over a significant period of time.

So none of your links contradict what the person you are replying to said.

Re: Signs of Liquid Water Found on Surface of Mars, Study Says

#170

Post by mturmon »

DanielBMarkham wrote: post #139
mturmon wrote: post #109

Earlier quoted context omitted.

I'm puzzled about why the existence of guidelines for contamination of other planets would be surprising. Note, the concept of "Planetary Protection" also applies to contamination in the reverse direction for sample-return missions, which are very much expected to be part of Mars 2020. I didn't know this before looking, but it turns out there are UN agreements, and something called the "Outer Space Treaty" to which t…

"Presumably something will be worked out as the reality comes nearer." One would hope so. I must point out that private space travel was entirely out of the question with NASA for many years. It's only been very recently that the idea has started to catch on -- and it's not universally lauded across the agency. Gotta wonder what kind of obstacles we're currently setting up (perhaps without fully realizing it) for any…

OK, I spent some time looking and according to the latest survey I could find (from 2014, http://mepag.nasa.gov/reports/Rummel_et_al_Astrobiology_14-S...), here is the state of knowledge:

[Sec. 6]

"Strong interest exists among various countries and private industries to send humans to Mars, both for short-term exploration and long-term colonization." (and on for 3 dense pages).

So, private ventures are part of their deliberations.

[Sec. 8, end]

"It will be impossible for all human-associated processes and operations to be conducted within entirely closed systems, so protocols need to be established so (1) human missions to Mars will not contaminate Special Regions nor be contaminated by materials (or possibly organisms) from them and (2) human activities on Mars will avoid converting Non-Special Regions to Special Regions and thus help control the spread of terrestrial microorganisms on Mars."

*

The basic strategy is to identify and avoid "Special Regions".

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