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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."
What?
If we can't Terrorform Mars then....
The Terarrists HAVE WON!
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Scientists discover that the ice cap is cotton candy, not water. The "beer-foam" scientists are devastated. Life continues exactly as before.
Your paranoia is about as subtle as the alien probe in your neck.
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.
Maybe someone should explain to the scientists we have to worry about not having our probes CRASH ON LANDING before we can worry about actually terraforming a planet.
Start the reactorrr!!
Sorry karma, I just couldn't resist.
Thats exactly the reason why you work as the IT guy in your uncle's company and not at NASA.
I dare say that they're not 'just' using this evidence, it's the only bit of evidence out of the datapool which makes for good press release.
...
If they say 'our spectrometer says that it is water', people won't know how that works or even why they believe it. But explaining the temperature difference between CO2 and H2O to the general public is a lot easier, so that's what we hear
I think MGO has a spectrometer or two aboard...
; -- the corruption of government starts with its secrets. a truly free people keep no secrets. --
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
Greenhouses could easily be built on the surface
for sufficiently large values of easy
There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
>
> Of course, you'd need to pick an "earth crosser" (well mars crosser), or the energetic considerations would be a bit steep.
Well, they've got it working for space probes. It's just a matter of scaling up. *rimshot*
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.