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Martian Canyons May Have Been Carved By Wind
sciencehabit writes Ancient canyons scar the surface of Mars, a relic from a time billions of years ago when rivers flowed on its surface. But water may not be the only factor that shaped these canyons—the wind whipping through them could be just as important, according to a new study of river canyons on Earth. Scientists studying chasms in the Andes mountains in northeast Chile have found that wind carves some canyons 10 times faster than water. The discovery may be significant for understanding how much water flowed on the surface of ancient Mars.
While here on Earth with a good 1 atmosphere of pressure, wind might be 10 times faster than water. Now how does that scale to Mars' 0.6% atmospheric pressure?
Seven puppies were harmed during the making of this post.
Water flowing over land is just a denser "version" of wind, right?
It's pretty obvious that Mars was primarily carved by arc discharge.
- In Soviet Korea, only old people loose all their bases to Natalie Portman's petrified hot grits overlords.
I'm pretty sure naturally occurring lasing is still on the table, and I find that highly likely compared to several of the options such as arc discharge, giant space worms, and a young, eccentric billionaire who traveled there to engage in some planetary bondage play, the scars of which haven't yet healed.
Is it just my observation, or are there way too many stupid people in the world?
Carved by wind? What does that even mean?
Ohhh, wind. Hard to tell the difference when it's written down.
It also ruins any attempt at making a joke about it. See above.
systemd is Roko's Basilisk.
Where's the kaboom?
Wind, water, lava flows.... Another on first consideration implausible one is electric discharge. But some pretty good points can be made about these matching the observations. I have never heard the proponents of that model provide a convincing and comprehensive explanation of what gets and keeps the discharge going, though.
that water could flow on it?
And what accounts for the difference in surface temperature, given that Mars's orbit didn't shift by that much?
Where are we going and why are we in a handbasket?
ianap but fluid dynamics is actually really interesting and relevant
everything behaves according to fluid dynamics principles...well...that's reductive but it's true for so many things including planets, light waves and typewriters
was it wind or water?
was it liquid water or water vapor?
see how the distinctions start to change?
this is about the recent "Mars had a huge ocean" news story...it was an easy pick for news editors, it's fun and has a cool graphic of an artists's conception of Mars with a huge ocean...i get it...
but it's all "fluid"...right?
Thank you Dave Raggett
I'm not saying it's aliens, but it's aliens.
Uhhh... actually the laws of physics, as far as anyone knows, prohibit MH370 from having made the erosion.
They don't do so for wind or water.
I am personally glad to see this headline, even if none of this is very meaningful. How many headlines do we see that seem to take the existence of valleys on mars for proof positive that there was water? At least this one provides a hint of objectivity to the tired formula.
While it won't account for all canyons, I suspect there could be Mars-specific mechanisms, such as layers of dust/ice/dry ice that build up over the ages and metamorph under pressure into stratified rock. Then something like a meteor strike disrupts the surface, exposing the strata at an edge, allowing the ice to sublimate, weakening the rock structure and allowing accelerated crumbling of the rockface, exposing more icy strata to the same forces of decay - including wind that blows away some of the dust released. This process would release a lot of smaller rock and dust, that sometimes looks like material washed down by moving water.
Somehow the first time I read this it came out Martion crayons not canyons. Confused the hell out of me.
John McPhee is talking with John Love, the last USGS geologist to map an entire state (Wyoming). John Love is saying the sediment in the Gulf of Mexico doesn't equal the dirt that is known to have been excavated from Wyoming. He thought water took half of Wyoming's erosional losses to the Gulf and wind took the other half.
"...in one dust storm several years ago a great deal of debris from Kansas and Nebraska and Colorado went into the Atlantic - a storm that lasted only a couple of days."
Such storms are frequent, and this one was not unusual in size or duration. It is noteworthy because its effects were studied and published, in the Journal of Sedimentary Petrology. When the dust appeared above the coast of Georgia - as thick haze - it attracted the attention of researches at the Skidaway Institute of Oceanography, near Savannah. The cloud of particles was two miles in height and satellite photographs showed its other dimensions: four hundred thousand square miles. With air-sampling and measuring equipment, the Skidaway people collected particles. They reported in that one storm enough dust to account for twenty-five per cent of the annual rate of sedimentation - from all rivers as well as the air - in the proximate North Atlantic.
"May" isn't the word you think it is.
To understand science, one has to understand that 'may' is in fact a central concept; it is the possibility that something may be true, that guides our research. In most cases, when scientists use the word 'may', it is because they think there is a very good possibility that this is true. In the case of wind erosion and canyons, I would say it is just a question of figuring out how much each factor - wind and water - contributed. Intuitively, water mostly erodes *down*, whereas wind erodes *sideways*, bringing material down to the water flow, where it can we washed away, or carrying it away as fine dust. The question is how much of each?
Misread as Martian crayons. Am much less interested after re-reading.