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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."
Even for terraformers!
Why? Because this tells us something about the temperature of Mars over the year, and allows us to compare the temperatures at different latitudes on Mars with those on our own planet.
[New findings] show that the souther polar ice cap is too warm at certain seasons to be dry ice.
Dry ice's temperature is -78.5C, or -173.3F. In 1960, Russians monitored a temperature of -127F at their station at Vostok.
The average temperature in Miami in Summer is +26C. The average temperature at the South Pole in its Summer is -3C. This is a factor of 8.666 recurring.
So.. let's say that the average temperature at the Martian South Pole in its Summer is around -60C, which is quite realistic, given that water is there.
Multiply by -8.666 and you get.. 15C. A bit colder than Miami, but perfectly livable, and the right temperature for humans.
Of course, there are some flaws in this theory but I'm quietly optimistic.
mogorific carpentry experiments
Well, I hope the atmosphere (what little there is) is still CO2, then. I hope they weren't wrong about that. That seems unlikely, though. I worry only because just five minutes ago I left a seminar about mars exploration and how probes with nuclear reactor generators would dissapate heat faster in CO2 than in most other gaseous surroundings.
The Mariner series of spacecraft went to Mars around that time period. I can't find a successful one in 1966, though. Here's the list:
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.
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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. --
From this page I'd say it was Mariner 3 or Mariner 4. HTH HAND.
However, IIRC much of the carbon dioxide on Mars is probably in the regolith rather than on the polar cap. It's just a lot harder to get to. It still might be possible to terraform Mars, but the job seems to be harder than first thought.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
Well, July 14th plus nine months equals 1966. Remember, it takes a while to get to there (unless, of course, those dates are the ddates when they flew by).
The Political Programmer
Mariner 4 was launched at the end of 1964. 1965 is the date of the actual flyby.
There were no Mars launches in 1966-68. Mariner 5 was originally built as a backup to Mariner 4, launched in 1964. When Mariner 4 completed its mission successfully, the backup was reoutfitted for a flyby of Venus.
Launch: June 14, 1967
Flyby: October 19, 1967
Mass: 245 kilograms (540 pounds)
Science instruments: Ultraviolet photometer, cosmic dust, solar plasma, trapped radiation, cosmic rays, magnetic fields, radio occultation
Nothing for 6-digit uids?
You got me wrong - there are seasons on Mars. The problem is that Mars' rotation & tilt are erratic, and that's due to the absence of a regulator (large satelite). In Earth's terms, that would translate to 6 month of winter in one year and one month in another. BTW, when the tilt of Earth's rotation axis changed by a single degree the impact on weather was huge.
The Raven
a) flimsy temperature evidence makes better news
b) It's not all that flimsy. If it's too hot during some seasons for CO2 to stay frozen, the ice caps wouldn't stay frozen during those seasons if they were mostly CO2.
Moon is only about 1/81 the mass of earth (it's surface gravitational force is one sixth of Earth's) and
Mars has (rather stable) seasons (see e.g. Season on Mars )
What are you talking about? The Earth has seasons because our axis is tilted 23.5 degrees from the ecliptic, and thus at different times of the year different hemispheres get either more or less direct sunlight. The moon has absolutely jack to do with this.
Mars has an inclination of about 25 degrees, just slightly more than us. Mars' seasons are actually more extreme than ours. It has a more eliptical orbit than Earth and makes its closest approach to the sun during Souther Summer, contributing greatly the global dust storms I'm sure you've heard about.
No, the main barrier to terraforming is the fact there's no atmosphere to speak of. In the long run, the low gravity and lack of tectonic activity will also be problems. These are major contributors to its current lifeless state.
Three words: Red Mars Trilogy. K.S.R. dealt with all the terraforming issues in detail... I was actually surprised at how deep he went into eco tech.
In any case, it would take more than ants, and a helluva lot longer than a few decades to change the environment on Mars into one we could use.
Not sure about the issue of radiation... there may be a way to have a thick atmosphere that shields the surface enough. I don't think normal radiation within the solar system is really that bad, it's the solar storms that getchya.
One other note: just because the polar caps aren't made of dry ice, doesn't mean there isn't a significant amount of CO2 and carbon locked into the regolith, and in the water itself. But yeah, there are much better gases for terraforming if you want to "Greenhouse" a bit. CFCs for example.
I've got a bad attitude and karma to burn. Go ahead. Mod me down.
The problem is that Mars' rotation & tilt are erratic, and that's due to the absence of a regulator (large satelite).
They're erratic over timescales of hundreds of thousands of years. If we ever do terraform Mars, large swings in the axial tilt will not be on the list of things to worry about.
65 million years since the dinosaurs died out, about 3 billion since the earliest evidence of bacteria (the last I looked)
TWW
"Encyclopedia" is to "Wikipedia" what "Library" is to "Some people at a bus stop"
Mars does have an ionosphere, You have an ionosphere when solar radiation strips away electrons from atmospheric gases.
Mars doesn't have a strong magnetic field though. The magnetic field keeps charged particles away from the planet, which otherwise would erode the atmosphere (this is why Mars has a thin atmosphere).
Hard solar radiation does make it to the martian surface, and in the absence of ozone or another long-UV absorber, would be a problem if we ever did terraform Mars. Buy stock in ACME umbrellas now.
It's far easier to take temperature measurement using other means, and those measurements are sufficient to show that it's too warm for CO2.
I'm not positive of this, but I would guess that ground based infrared spectrometers (like what's on NASA's IRTF) may not have the resolution nor the signal to noise capabilities to do the detection. No that I think of it, there are several plausible reasons why you can't do the detection from ground based telescopes, but I would need to check them out before sticking my neck out and posting them.
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Good points, but one of the benefits of CO2 is that plants want it. Insects could turn O2 into CO2, but insects won't last long without plants...and that's not even getting into what it takes to grow chickens and eggs. ;) You see the problem. Getting Life to survive is really no issue, because that's all life does. The tricky bit is getting reasonable precursors and conditions for life in place. If you can do that, your subsequent decisions won't even matter much, because you can be sure the thing will take off without you and before you know it it's calling you up on the spacephone talking about [mp]aternity.
:)
To transplant an Earth-type ecology, you're going to need remarkably Earthlike conditions, and this is probably unfeasible. What people have looked at is importing something like (what they envision as) primordial Earthlike conditions and letting it stew for a few hundred (or thousand) years. The interesting thing to me is that this is still called "terraforming", when what comes out of it really won't really be Terran - it'll be novel. The starting factors would likely be genetically engineered, and if there's success it'll be through rapid adaptation. The life you get is pure Martian. Just as Ray Bradbury observed.
We don't need CO2 as much as we need Nitrogen in the atmoshpere and in the ground. Well anywho we need Oxygen, Nitrogen, and Carbon Di-Oxide all together (as well as inert gasses but they're miniscule). In order to get a viable ecosystem of any kind of proportions we need all 3.
I tried to think of a good sig, and this wasn't it.
"Terraforming" is the act of changing a planet to resemble Earth, especially for the purpose of sustaining life from Earth.
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This is beginning to be a bit off topic, so I won't spend too much time here.
I can't speak for all of the anti-Greenhouse Effect folks, but the biggest problem that I have with it is that the whole debate is too politically charged, with scientists doing research with pre-conceived results, questionable sponsors, and a focusing too narrowly one just one or two root causes to the problem. Don't blast me here, because I've spent too much time with real researchers fighting for grants, tenure, publication, conference presentations, and all of the other acedemic BS that almost makes a mockery of science. Despite all of that, there are people who are genuine in their desire to do scientific research, but a real question has to be asked if they are getting lost in the background noise of simple charlitains who are trying to find a way to get a quick buck...by faking science or simply being lazy because they don't care.
I also say that Mars is a good example of what is going to be required to prove the "Greenhouse Effect" on a planetary scale, because it will prove on a planetary scale what kinds of activity is going to be required in order to actually affect the environment. If it is going to be so difficult, then it will be hard on the Earth. The opposite is also going to be true.
In other words, terraforming Mars would be the real final proof that massive industrial activity really has an effect on the whole planet. And if we succeed at warming up Mars by 10-20 degrees, it will be a useful alternative to Earth if we really are screwing it up permanently.
Forgive the nitpick, but the Mars Observer wasn't involved in this. It was a combination of data from Mars Odyssey and Mars Global Surveyor. Observer isn't even mentioned in the article...gotta proof-read those submissions, folks. :-)
Contact was lost with Observer shortly before it was to enter orbit around Mars.
See JPL/NASA for more information on the 2001 Mars Odyssey and Mars Global Surveyor
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