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Mars May Be Dry After All
BillC writes "Boston Globe reports that all the Martian features which looked like water just under the surface might merely be the land features left behind when glaciers retreated thousands or millions of years ago."
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Actually, most scientists believe that the majority of Mars's atmosphere and water vanished into space. Mars has less mass than Earth, which also implies a lower gravitational pull. It turns out that the solar wind (as well as convection) is enough to sheer away critical molecules from the atmosphere.
So water would evaporate, and maybe 0.005% of it was blasted away by the solar wind. Give it a few million years and you're left with a very thin atmosphere and no water. Consquently, this is also why the moon cannot support an atmosphere. It's also why if anyone tells you they can totally teraform Mars into another Earth, they're lying.
Another poster has answered your question about how Mars loses water. No magnetic field -> dissociation of water into hydrogen -> lose hydrogen to space.
:)
Perhaps the question should really be: How is it that Earth came to have so much water? Last I heard, scientists were still arguing about this, but cometary impacts are one likely source. In addition, it would seem that the Earth's magnetic field helps protect what water we have (in contrast with Mars).
We live on one lucky planet
Is this the promised end? Or image of that horror? KING LEAR
According to my astronomy teacher, the core of Mars cooled off and solidified, eliminating the magnetic field. You need circulating currents of material in the core to produce a magnetic field. Another problem associated with a low mass planet.
"Millions of disgusted viewers report that all the narrative features which looked like talent or good plot just under the surface might merely be the crap left behind when hollywood writing talent retreated thousands or millions of years ago."
um, hello? Unless we're talking about frozen methane or some other weirdness, glaciers = water.
Using your sig line to advertise for friends is lame.
My local Wal-Mart is selling a product called Martian Mud. Since one half of the recipe calls for water (I'm assuming Martian water), there is no doubt that Mars has an ample supply. After all, Sam Walton wouldn't get involved in a venture of limited cash making capacity. And we all know that Sam was an honorable man, and that he wouldn't be trying to pull the wool over our collective eyes.
As to Earths water leaving the planet, I would say yes, it does, but only in very small amounts.There are water molecules present in the air all around us. The average velocity of any given molecule of air is ~330 metres/sec, the speed of sound. However, this is only the average. The velocities follow a standard distribution or Bell curve. Therefore an incredibly small number of molecules will attain escape velocity, and some of these molecules will be water molecules. If the altitude is high enough, the water molecule will be able to escape from the Earths gravity well entirely. This is why the moon cannot sustain an atmosphere - a small (but larger than Earths) proportion of the moons atmosphere would escape, and after a few million years it would be left with nothing.
The only other mechanism I can think of is through meteorite impact. Fragments of rock which contain embedded water could be hurled into space from such an impact. I doubt that water or Ice could do it by itself, due to boiling and mixing with the rest of the atmosphere.
Overall, then, bugger all water gets off Earth (or Mars), but a small teeny tiny bit does.
The water Mars once had is, for the most part, underneath the surface, much like permafrost. Frozen ice isn't much different from rock in a sense, it just gets churned up with all the other solids. However, because it is less dense, it does tend to stay towards the surface.
KTB:Lover, Poet, Artiste, Aesthete, Programmer.
There is no
Mars has no magnetic field, therefore no protection in the atmosphere from solar radiation that will take a water vapor molecule, make that molecule it's bitch, and split it wide open into oxygen and hydrogen, the hydrogen floats into space, and the oxygen combines with iron in the soil to make iron oxide, giving the planet it's rich amber hue.
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
I am simply asking for a logical explanation of where the water went.
:-)
Duh, A giant Spaceship that turned into a giant vaccum cleaner (IIRC, Lord Dark-helmet lead the mission) and sucked up all of the oxygen (for their Perri-Air plants), and all of the water accidentally went with it.
They weren't as successful on their next mission:
Druidia
Doh!
Wrong.
The first article dealt with the origins of large channels on the surface of Mars. This deals with the presence of actual water presently on the planet.
Read before you flame the posters.
The widely accepted theories put varying emphasis on the following:
1) Frozen in the ice caps
2) Frozen into the regolith (permafrost layer)
3) Underground, in large geothermically heated pools.
Most of it would likely be found in the northern hemisphere, as this is where we see the most signs of ancient ocean/water erosion. Also, it's important to keep in mind that the northern polar ice cap is estimated to contain about two million cubic kilometres of water.
To answer your question, planets follow "lifecycles" of cooling, warming, cooling, etc. It's all mostly theory, but it's been proposed that while a planet the size of Earth can get locked into a cycle of freezing/thawing (the ice ages), a smaller planet such as Mars may not be able to have such a continuous cycle, or the cycle may be much longer. Hence the lack of liquid water...
Uhh, that looks OK. We haven't seen that number yet.
There is no reason to think it, considering Mars is relatively Earth-like and life happens very easily.
Life has not happened easily anywhere but Earth that we know of. Unless you have proof of life that has originated somewhere other than Earth, you can't make this statement. We have no reason to think that life occurs because of water, it just happened to be like that on our speck of dust. That is not to say I agree with the person who you replied to, because it very well is possible that there is life, but I won't believe it until there is proof.
: There never were lifeforms on Mars
This is very, very unlikely. Where there is liquid water, there is usually life. Life is made up of the most common elements in the universe, and for life to exist all you really need is water and some basic primordial soup. The chances of Mars never having had even the lowest form of bacteria are incredibly slim.
Again, you are taking science that you learned from watching Star Trek and applying it to real life. We have not found any life outside of Earth at this point in time. We may never find any, as the universe is really big, and, well, we aren't. So, the way a real scientist looks at the situation would be that, yes, it is possible for life to exist outside of Earth. We can not make any assumptions about that life, because we have a very limited amount of data to compare it against. When people base their knowledge on huge assumptions and make giant leaps of logic to support their beliefs, it invalidates the real science. You have to be skeptical, but open to new ideas. Try to understand, that by debunking someone's opinion with your opinion, rather than facts, you can't win. I know that there is no way humans can know anything 100% for certain, but, at least have some proof to back things up before you go around spreading your ideas to be facts. This is addressed to both people above me in this thread. Don't make science into a religion. There is a place for religion in people's lives, and there is a seperate place for science. When you base your "beliefs" on what you want to be true, rather than facts, that is a religion. I am not saying there is not any deities either. There may be, but I have no proof so I can't say.
So I won't be completely off-topic in this thread, let me just say that the only real way to know what's over on Mars is to send some people there. C'mon Nasa...it'd be fun! :o)
Mas vale cholo, que mal acompañado.
Does Guinness know about this?
Looks around nervously...am I allowed to say that? Please don't sue me!
--meredith
--meredith
Sometimes a scream is better than a thesis