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A Third of Mars Could Have Been Underwater
Posted by
timothy
on Tue Nov 18, 2008 09:39 AM
from the younger-hotter-ocean-that-is dept.
from the younger-hotter-ocean-that-is dept.
Matt_dk writes "An international team of scientists who analyzed data from the Gamma Ray Spectrometer onboard NASA's Mars Odyssey reports new evidence for the controversial idea that oceans once covered about a third of ancient Mars.
'We compared Gamma Ray Spectrometer data on potassium, thorium and iron above and below a shoreline believed to mark an ancient ocean that covered a third of Mars' surface, and an inner shoreline believed to mark a younger, smaller ocean.'"
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To prove it... (Score:5, Funny)
Re:To prove it... (Score:4, Insightful)
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Re: (Score:3, Interesting)
I have recently read a book that was supposedly written by an alien. He claimed that: the Moon is empty inside and is a home to a race of living beings that are on a very high level of spiritual evolution, the global warming is caused solely by the sun (and the other planets of the solar system are warming up too), that there was a very advanced (more advanced than ours, both technologically and spiritually) civilization on Earth millenia ago, that vanished due to a world war in which
Re:To prove it... (Score:5, Funny)
ALL HAIL XENU.
Parent
Re:To prove it... (Score:4, Informative)
Parent
Re: (Score:3, Interesting)
There is no evidence [of] the existence of god. I'm with you so far.
There is no evidence [of] the nonexistence of god. Even if we accept that this is an accurate statement about the beliefs of atheists—which I do not think it is—this still doesn't make atheism a religion.
Your error lies in the assumption that the existence of god is akin to flipping a fair coin. If a coin is flipped and the result is concealed by placing it under a hat, for example, it is reasonable to assume that the coin i
Re:To prove it... (Score:4, Interesting)
Parent
Re:To prove it... (Score:4, Insightful)
How much terraforming would you have to do to remove all evidence of an advanced civilization and a world war?
If a nuclear bomb went off in New York City, and we wanted to pretend there was nothing there, we would have to knock down every building, melt down the metal, and place it back in the ground, find some way to convert plastics back into petroleum, plant a forest over the entire city, remove all the pollution and radiation from the air, dig up every corpse and remove items such as cell-phones, watches, and anything that is not biodegradable. Now, imagine doing this, with every city in the world...
Couldn't they come up with a simpler cover story that allowed for an advanced civilization to wipe themselves out? Honestly, my point is that, for most notions, such as this, you have to ask yourself, how much effort, control, and sheer genius would be needed to hide a secret this big, and then ask, what are the odds of someone pulling it off?
Parent
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How does he account for the gravity?
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Never mind that, just try getting 1.21 jiggerwatts out of those solar panels.
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What is The Truth about Mars? (Score:2, Insightful)
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The planets are getting closer to the sun, but not nearly fast enough to be interesting.
Re:What is The Truth about Mars? (Score:4, Funny)
> The planets are getting closer to the sun, but not nearly fast enough to be interesting.
You mean interesting as in "Hmmm, we might want to have some means of space exploration in the next century at the latest" or interesting as in "My hair is on fire! My hair is on fire!".
Parent
Re:What is The Truth about Mars? (Score:5, Interesting)
You mean interesting as in "Hmmm, we might want to have some means of space exploration in the next century at the latest"
A century is a very short amount of time on the solar timeline. The Earth won't fall into the Sun for 5 billion years or so, and even then, the Sun will have lost enough mass that models predict the Earth may be flung off into deep space rather than falling into the Sun.
The more immediate concern is that over the next 1 billion years, the luminosity of the Sun will increase about 10% or so, which should be fairly devastating to life on Earth. But, thats due to the Sun getting older, not the Earth getting closer.
Parent
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Re:What is The Truth about Mars? (Score:4, Interesting)
At some point we have massive evaporation, which would tend to go catastrophic, i.e. Venus (water vapor is extremely potent as a greenhouse gas). A temperature above which proteins in most organisms coagulate would bring us down to archea. Photosynthesis in its current form also prefers lower temperatures. We know very little of what situations complex multicellular life can really adapt to, but we can say that Earth would no longer be within the range that we consider to be habitable when we do armchair analyses of exoplanets.
It's not life as we know it, Jim.
Parent
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Yes, we are all concerned that in 1 billion years it will get 10% hotter on the earth. Let me stock up on sun-screen in case the my local grocery store runs out.
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Usual theory is that orbits stay constant (since mass is basicly constant) but the radius of the Sun expands past the current orbit consuming the planet it it's firey corona of love.
I also don't think getting flung off will be the end of life on the planet. I mean just look at the last time [wikipedia.org] it happened.
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I mean that the planets are on an inward-spiral orbit. While ideally they would keep perfect elliptical orbits, solar wind pushes them outward and drag caused by the matter in space pushes them inward (well, decreases their velocity, which causes them to fall inward). I forget the rate for this, but I do recall it's so slow that everything else interesting in the solar system (e.g., the Sun entering the later stages of life) will happen first.
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Whatever caused the devastation on Mars, could be avoided on Earth with the correct approach to discovering the truth.
Mars is devistated?
Mars has no water/atmosphere because A)It is small and B)It lacks a magnetosphere (which is because its core has cooled which is 1) because it is small and 2) because it lacks a large moon). With no pressure, water sublimates. With no tectonic activity to introduce more, and less gravity to attract more from space, it dried up. Distance+no greenhousing also means its cold.
For the reasonable future, Earth has none of these problems. Our current threat is "random catastrophy" or "runaway g
Yes, but... (Score:3, Funny)
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Potassium Salts (Score:5, Informative)
Dross (Score:2, Interesting)
We are living on dross, http://en.wikipedia.org/wiki/Dross the impurities on the surface of a molten ball of nickel/iron
that takes billions of years to cool, geologically speaking.
Global cooling is the long range prognosis for us, just as Mars. Mars gets less solar power, being more distant from the sun.
Mars HAD an earth-similar composition 2 billion years ago. It is what the Earth will look like in the future. Deal with it.
take care with hononyms :) (Score:3, Funny)
We are living on dross
I didn't know six and a half billion of people live in a small Austrian municipality. It must be really all too crammed up there, probably worse than HK. But at least all enjoy living in the birthplace of a music composer.
But the big question remains (Score:2)
Google Mars (Score:2)
Check out Google Mars!
http://www.google.com/mars/ [google.com]
How cool is Google?
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Is that a joke?
I'm fairly certain that if you looked at the Earth and kept panning east or west, you'd see the same image over and over. Try it with Google Maps. [google.com]
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Why is it such a big deal? (Score:2)
The argument that understanding the way Mars once was helps us understand ours own planet a lot better seems
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The reason the people are researching this is intellectual curiosity, and for the grant money that pays the scientists bills. This information may or may not have any use to anyone alive today, but it is a part of the puzzle of how the universe works. Perhaps in the distant future, this information and countless other data points will help humanity solve some problem. Or it may be just a useless piece of trivia. The point is, we do not, nor can can we know what things we learn about our universe will be
Two sides to this. (Score:3, Interesting)
First, as others have noted, there is a massive level of sheer scientific curiosity. Prior to this, we didn't know of any planet other than Earth that ever had liquid water on it. We had no idea if such planets were rare or common, or even how to identify them if the water wasn't extremely visible and obvious. This allows us to know so much more about planets and their evolution in early solar systems than we ever knew before.
Then, there is another side. Water, particularly if it is mildly acidic, leaves op
Why controversial? (Score:5, Interesting)
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Weird might be a better choice than controversial (Score:5, Insightful)
Parent
My theory (Score:2, Funny)
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Too far fetched?
Yes...
I believe that...
Do you really? I actually really, REALLY hope not. "Playing with the idea" is alright (wrong, but nevertheless, alright), but actually believing it would be pretty sad.
It's a cute idea, but it's so far out of the realms of possibility due to the basic physics of what you're describing, the positions and orbits of the planets as they are, and just everything we know about how our solar system formed.
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So, let me try to understand.... (Score:2)
All other planets are inferior potassium.
New evidence (Score:2)
Your thinking (Score:3, Funny)
Your thinking and opinions are positively antediluvian.
For what it's worth, I don't think scientists deny the possibility of a global flood. They just don't see much evidence for it.
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Re:Your thinking (Score:5, Funny)
Eh, whatever. Mostly it was about using the word antediluvian.
Parent
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To be fair, there is some evidence for a global flood. All you have to do is look on the tops of various mountain ranges and you'll find plenty of fossils and minerals to indicate is was underwater at one point.
Of course, you have to ignore the fact that it can all be explained by plate tectonics.
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