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More on the Mars Ice Cap
bfwebster writes "In a striking example of how a preliminary (but wrong!) scientific conclusion can persist for decades, Space.com has a story about how the south polar ice cap on Mars is mostly water, not mostly carbon dioxide (dry ice), as has been stated since the late 1960s. The new finding is based on analysis of Mars Observer readings that show that the souther polar ice cap is too warm at certain seasons to be dry ice. This finding has negative implications both for those claiming that liquid flow structures on Mars were caused by C02 instead of H20, as well as those who were hoping to use all that CO2 for terraforming."
Terraforming by CO2 looks like it is no longer immediately feasible. However, since most of the minerals are below the surface anyway, it should be possible to create domed structures using the terrain of mars currently in existence to build habitats. Greenhouses could easily be built on the surface to produce food or grown underground by artificial light. Extracting water from the caps could be done and piped into colonies elsewhere. We hoped it would be easy to drop algae or some other organism on mars, release the CO2, and let nature take its course to heat up the planet. Now we just have to work a little harder. I'd still like to vacation on mars before I die, regardless of whether a spacesuit would be necessary.
As long as there is a Second Amendment, there will always be a First Amendment.
a damn probe down there?
Please forgive me if I'm wrong, but isn't water(drinkable?) on Mars a good thing for those that want a colony? Hell, it could cool help operate a nuclear power plant and mixed with ethynol help colonist morale. Those opposed to this idea can mix methynol with the power planet's old cooling water(the stuff that's been in the inner loop for years.) Or is the camp that believes the caps are CO2(middle school science teachers) to the point of sabatauge!? Better call the probe a "welcoming guesture to aliens" and it'll get through.
BTW Mr. Watson, I did get question #3 right on the "planets quiz." I lied about my dog chewing the DB25 connector off my serial printer, so we can call it even.
You can't judge a book by the way it wears its hair.
Might I point out that factors between temperatures are meaningless when using a non-zeroed scale? 26C is not eight-odd times warmer than -3 -- you're looking at 299K vs 270K. Thus a more reasonable (but still incorrect due to the differences in the size of planet, etc. mentioned by others) would be to take that -60C (= 213K) and multiply it by 1.107 to get ~236K, or -37C, which is -34F.
What kind of spectrometer?
...)
Mass?
Optical? (transmission, emission, raman, IR, UV...)
Nuclear? (alpha, beta, gamma, neutron activation,
The only spectrometry possible from the orbit is a passive one. The optical spectrum of the solid chunk of (dry)ice does not contain any characteristic lines or bands. Good luck with determining the "exact chemical composition".
Now if you had a probe LANDED on a pole than you could determine composition with almost arbitrary precision.
Those guys were obviously trying to guess composition from the orbit
Ok,
Here is why Terraforming is good. It turns an otherwise dead planet into a living one. Think beyond us mere humans, and thing of life as a whole and what it has done since its beginnings billions of years ago - life expands to fill every available niche. Life has expanded and become the massive and complex biosphere that it is today. Life has also experienced numerous near total extinction on numerous occasions. Life has now finally gained the capability of leaving its womb planet and expanding outwards to other worlds.
Of course we are talking about life expanding onto other worlds as long as there is no pre-existing life, especially complex life there already. As long as Terraforming meets those ethical requirments I have yet to hear a single reason not to terraform. After all we are only talking about the perpetuation of life itself. I almost would be bold enough to say, "that if you are against terraforming, then you are basically against life itself".
Planet P Blog
www.enthea.org
Does Mars have an ionosphere protecting it from solar radiation? I was taught in school that that is one of the reasons Earth can sustain life, because most of the radiation from the sun is stopped from hitting the surface by the magnetic field of the Earth. If Mars does not have a sufficient ionosphere, is there any hope? can buildings keep their occupants safe from the radiation?
Last I heard, water causes a much stronger greenhouse effect than CO2.
So the fact that the ice caps consist of water rather than solid CO2 means nothing but GOOD!
Not only do we have something even more useful for trapping heat (if we could melt it), but we have something that Earth-based life requires quite a lot of to survive.
Strange, some of the conclusions people come to when the find that a pet project needs a slight tweak.
IMO, I see it as a much bigger problem that Mars lacks a strong, relatively-stable magnetic field. If we hope one day to live there, we don't *need* to bother making its atmosphere human-friendly, because we'd need to live a few hundred feet underground anyway to survive the constant bombardment of the surface by "hard" radiation.
Now, for a personal oddball idea, one of the science projects from the ex-Columbia inspired me. Insects need only a small fraction of the oxygen of mammals, far less water, and can survive even a hard vaccuum and fairly high levels of background radiation. The experiment with "ants in space", as covered on Slashdot a couple weeks ago, led me to wonder, why don't we just ship a few dozen different insect colonies to Mars and let *them* terraform it? Ants apparently do much better in lower gravity, they "farm" aphids and fungus (of which some strains could conceivably survive on the chemical-energy-bearing soil on mars, thus providing food for the ants), they clean their own microenvironment... Perfect for what we need. Let the little guys build up Mars' biosphere for a few decades, then other introduced organisms would have a much better chance for survival.
Mars also contains CO2 in its soil. This is in two forms: (1) CO2 directly adsorbed onto the (porous) rocks and dirt, and (2) CO2 in ice form mixed into the soil, possibly mixed with water ice as well.
Read here to learn more.
The extent of these soil deposits is almost completely unknown and difficult to estimate. Nevertheless, if the surface temperature were raised then some portion of this trapped CO2 would outgas. (This would be akin to obtaining liquid/vapor water by heating a section of Siberian permafrost.) Because CO2 is such a good greenhouse gas, there might therefore exist a temperature threshold beyond which the outgassing of CO2 and subsequent greenhouse heating would push the planet into a self-sustaining "hot" mode.
Or it may be the case that too much of the CO2 on Mars has either been lost to space, or is chemically locked up in carbonate rocks. This is a numerical question that won't get answered until we have the ability to bore into the surface and measure the free CO2 content.
I'm personally doubtful of these "heat it up and it will automatically fix itself" scenarios. If Mars did sustain a liquid water ocean at some point (an amazingly we still don't know the answer to that for sure), then something dramatic must have happened to make it shift into the cold, dry climate that exists today. My likeliest candidate would be the cooling and freezing of the planet's core, and the subsequent cessation of volcanic activity. Without volcanos, CO2 gets locked up in carbonate rocks and it never cycles back into gaseous CO2. The same thing could happen to the Earth someday, but fortunately the Sun will have long since gone supergiant and vaporized us in our tracks.