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Water Flowed Recently on Mars
elfguygmail.com writes "According to to Space.com 'Small gullies on Mars were carved by water recently and would be prime locations to look for life, NASA scientists said today.' "
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Water Flowed Recently on Mars, NASA Scientists Say
By Robert Roy Britt
Senior Science Writer
posted: 24 August 2005
07:57 pm ET
Small gullies on Mars were carved by water recently and would be prime locations to look for life, NASA scientists said today.
There have been many studies of Martian gullies that concluded water was involved. But most of the features are ancient, or if they seemed modern then there were questions about how the water could stay liquid long enough to do the carving.
Scientists know there is a lot of water ice on Mars, locked up at the poles and beneath the surface elsewhere.
Water is a key ingredient for life as we know it, and other scientists have speculated that life on Mars, if there is any, could lurk just beneath the surface where ice melts in pockets.
A closer look
The new study suggests water may still bubble to the surface of Mars now and then, flow for a short stretch, then boil away in the thin, cold air.
The conclusion is based on computer modeling of the atmosphere and how water would behave.
"The gullies may be sites of near-surface water on present-day Mars and should be considered as prime astrobiological target sites for future exploration," said Jennifer Heldmann, the lead researcher from NASA's Ames Research Center. "The gully sites may also be of prime importance for human exploration of Mars because they may represent locations of relatively near surface liquid water, which can be accessed by crews drilling on the red planet."
Any potential long-term human presence on Mars would require a water source, both for drinking and to be broken down into hydrogen as fuel for return flights.
The claim that water carved the gullies is based on the shape and size of features spotted by NASA's Mars Global Surveyor.
Short gullies
"If liquid water pops out onto Mars' surface, it can create short gullies about 550-yards (500-meters) long," Heldmann said in a statement. "We find that the short length of the gully features implies they did form under conditions similar to those on present-day Mars, with simultaneous freezing and rapid evaporation of nearly pure liquid water."
Some of the gullies taper off into very small debris fields or leave no debris at all. That implies the water rapidly froze or evaporated.
Given the low air pressure on Mars, water would boil in a flash, the researchers say, so it is doubtful that ice accumulates in the gullies.
The findings will be presented next month at a meeting of the American Astronomical Society's Division for Planetary Sciences in Cambridge, England.
No, humans (nor any terrestrial multicelled organism) cannot live in the current Mars climate. The atmosphere is made up of carbon dioxide at very low pressures. Were you to step outside, your time of useful consciousness would be measured in seconds (and no, holding your breath won't work - you wouldn't be able to hold an almost 15 psi differential in your lungs).
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FTFA: "The new study suggests water may still bubble to the surface of Mars now and then, flow for a short stretch, then boil away in the thin, cold air.
So, based on that alone, no the climate would not sustains humans. On parts of Mars, the day-time temps can reach ~20C, but the night-time is still too cold for life. Also, the atmosphere is only ~0.1% oxygen, compared to ~21% on Earth, and ~95% carbon dioxide compared to Earth's So bottom line is... glass domes!
IIRC, water boiling isn't a matter of temperature, but rather atmospheric pressure. The less pressure, the lower the temperature for water to boil. That's why water boils more quickly at higher altitudes than at lower altitudes here on Earth. Ever notice most baking goods include alternate baking directions for baking a cake in high altitude?
Taking guns away from the 99% gives the 1% 100% of the power.
Water doesn't boil in cold air, but it's boiling point is dependent on air pressure. If you're at high altitude you have to boil eggs longer, since the boiling temperature is lower, for example.
The Martian atmosphere is much thinner than earth's, even at the highest peaks. I think the air pressure at Mt Everest is about 20% of sealevel, while on Mars it is 0.1%.
I don't have the numbers here, but I assume the physical foundation for this story is that at that pressure, the boiling temperature is below the freezing temperature, so water really can't exist stably in fluid state.
We may have thin air on the top of mountains, but the atmospheric pressure on Mars is 1/150th that of sea level on Earth (as measured by Mariner 4). The triple point of water (when water can equally exist as steam, liquid water or ice) is ~.006 atm (~1/150th of 1 atm) and .0098C. Any temperature on Mars above .01C, therefore, will result in water boiling.
Boiling point is directly related to pressure. As pressure drops, so does the boiling point. That's why you have to be careful of cooking at higher altitudes. In general terms, the lack of air pressure makes things happen at lower temperatures, so things take longer to cook, because even though water is boiling, it's not as hot.
Or, to think of it another way, the state of matter is a function of how much it gets pushed together. H20 is liquid until it has enough energy for the molecules moving around in it to push against the molecules of atmosphere and escape from the mass. When it loses that energy, it gets forced back together. Less air pressure means less stuff pushing in means less energy is needed to escape. It's not an entirely perfect mental picture, but it'll get you close.
Never confuse volume with power.
You're referring to chirality (often called "handedness"). There are several kinds of chirality - for example, there is the question of why we only use a protein folded in a certain pattern instead of its mirror image, as well as the more fundamental question of why the amino acids that compose the protein are themselves a certain chiral form.
The "radiation" theory is interesting, but I find a much simpler theory quite sufficient: two dimensional boundary interfaces. Picture that, say, you have some organic molecule forming on top of a grain of quartz sand underwater. There are different forces acting on one side of the assembly site than the other. The side that forms next to the water will not be likely to form in the same shape as the side that forms near the quartz.
Boundary interfaces abound in the universe - almost every joint between grains in almost every rock, from the surfaces of those rocks, from organic deposits, to liquids and gasses. If a certain substrate acts as a catalyst for forming a given molecule, and the molecule is rarely formed otherwise, it's only natural to expect that chiral form to come into play. Once the more dominant form is incorporated into a lifeform, it is "locked in" - more of that form will be created to help the lifecycle, while the other form won't be renewed.
Are there any deer in the theater tonight? Get 'em up against the wall.
It wouldn't decimate the beliefs of Flying Spaghetti Monsterism. It was He who put the life there to get us go into space, using his noodly appendage.
You're wrong. The very first chapter of the Quran starts with the words:
"Praise be to God, Lord of the Worlds"
Several places in the Quran, it is said that God repeats creation. And there are several indications that this world was not the first.
--- Tao
Nazi Germany. Soviet Russia. In fact, the socialist implementations derived from Marxist theory were (are) explicitly atheist, and perpetrated horrible crimes against millions of dissenters (still do, in places like China and Cuba).
Any sufficiently well-organized community is indistinguishable from Government.
The boiling point of any liquid is a function of both pressure and temperature, a point which you yourself seemed to make later in your post. Check out this article on phase transitions for more technical discussion. (For yet more info, follow the link in the article pertaining to critical points.)
It's entirely possible for three material phases (solid, liquid, gas) to exist simultaneously for a given substance if you have the right combination of temperature and pressure; this is called the triple point.
Not sure where you're getting your numbers from, but that's almost certainly wrong. According to this article:
So if the boiling point of water is 69 degrees Celsius at 260 millibars, it's most assuredly far lower at 10 millibars. Assuming that the surface pressure on Mars is 10 millibars (which is 1 kPa), you can calculate the boiling point there. There's a handy boiling point calculator to assist with this; for 1 kPa of atmospheric pressure, you get just above -11 degrees Celsius as the boiling point of water. (This temperature is well within the typical temperature swing for the planet Mars. You can find the temperature and atmospheric pressure ranges at this site; the temperature ranges from -140 C to 20 C, with the average at -63 C. Pressure varies from 6.8 mbar to 10.8 mbar.)
The Church of Jesus Christ of Latter-day Saings religious movement has been saying that God created life on Earth AND life on other worlds for 200 years now.
If God can create one world, and all life on it, why not others? Just because Scripture is silent about life elsewhere in the universe doesn't mean it doesn't exist, only that it has nothing to do with His plan for Earth.
Many theologians would point you to the fact the creation myth puts the creation of earth on the first day, and the creation of life on the third, while heavenly bodies aren't created before the fourth. Ergo, there is no life on them.
Then again, theologians have widely altered their long-standing literal interpretation of 1 Chronicles 16:30, Psalm 93:1, Psalm 96:10, Psalm 104:5 and Isaiah 45:18 - saying earth is unmoving, and the center of the universe - when confronted with the facts. So I fully expect that when aliens are found, theologians will promptly stop to see this contradicting scripture.
Actually, there are writings from Moses which show he had a knowledge about life beyond earth.
Like here: http://scriptures.lds.org/moses/1
verses 33 to the end
(sorry to be an anonymous coward but i'm too lazy to register)