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Maps Show Mars Was Once More Like Earth
vrioux writes "NASA scientists have discovered additional evidence that Mars once underwent plate tectonics, slow movement of the planet's crust, like the present-day Earth. A new map of Mars' magnetic field made by the Mars Global Surveyor spacecraft reveals a world whose history was shaped by great crustal plates being pulled apart or smashed together. ."
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I wouldn't be surprised to find that the majority of solid planets that we examine undergo the same basic geologic mechanisms. Tectonics, subduction, spreading, etc, are probably far more common in the universe than we think.
Be a real patriot: Question authority. Think for yourself. Formulate your own conclusions.
Seeing as how we do not behave exactly like every other animal...
Please tell me you're being facetious. I'm sure you'll find that no two types of animals behave *exactly* alike. However, a whole lot of them (including us), do exhibit many similar behaviours.
Be a real patriot: Question authority. Think for yourself. Formulate your own conclusions.
... it also appears to have been ruled by giant purple spiders.
Rubbish. We came from the Pak homeworld.
In other words, no. We, as in humans, didn't come from Mars. We're definitely mammals, closely related to the other great apes. It's about as plain as you could ask for at every level from DNA right through to gross anatomy.
It is conceivable that life originated on Mars and spread to Earth in the days of nothing but single-celled organisms, but that's quite another matter.
Real Daleks don't climb stairs - they level the building.
Here's the journal abstract:
0 2v1
http://www.pnas.org/cgi/content/abstract/05074691
"Mars currently has no global magnetic field of internal origin but must have had one in the past, when the crust acquired intense magnetization, presumably by cooling in the presence of an Earth-like magnetic field (thermoremanent magnetization). A new map of the magnetic field of Mars, compiled by using measurements acquired at an 400-km mapping altitude by the Mars Global Surveyor spacecraft, is presented here. The increased spatial resolution and sensitivity of this map provide new insight into the origin and evolution of the Mars crust. Variations in the crustal magnetic field appear in association with major faults, some previously identified in imagery and topography (Cerberus Rupes and Valles Marineris). Two parallel great faults are identified in Terra Meridiani by offset magnetic field contours. They appear similar to transform faults that occur in oceanic crust on Earth, and support the notion that the Mars crust formed during an early era of plate tectonics."
Does that mean the Earth will end up like Mars in the future?
And how will this data help us terraforming Mars?
Far from answering, I think this only leaves us with more questions asked.
Martians are NOT amused by this comparison. They find it degrading, humiliating and defamatory.
"Earthlings have never come close to inventing a Illudium PU-36 Explosive Space Modulator, nor can the 19.7 km height of Mt. Everest even touch Olympus Mons with an altitude of 27 km!", says Mars local, Marvin.
He who knows best knows how little he knows. - Thomas Jefferson
All planets (like our own) which have a dynamic liquid core have magnetic fields. The strength of the field depends on how large and dynamic the molten core of the planet remains. When planets form, they start as a liquid lava rock, and slowly cool over millions of years. As they cool, the outer crust (or mantle) solidifies, while the core remains molten. This is true of any solid planet (not gas giant) therefore any rock-type planet would most likely of had a magnetic field at one time. Mars unfortunately is far enough from the sun that it has cooled to great depth inside the planet, reducing its liquid core to a very small percent of its original size, reducing and almost eliminating its magnetic field, which is at present very weak. Another proof of this is the lack of volcanism on Mars, which by examining the topographic features was once very active.
I think it's far more likely we came from Golgafrincham. How else could we explain our penchant for sanitizing telephones?
We're incredibly similar to every other animal - same basic chemistry, most of our genome the same. We have the same ancestors as every other living thing on this rock. A better (and open) question is whether all life on Earth is descended from (primitive) life that originated on Mars and was carried here by meteorites before Mars became uninhabitable.
I am trolling
No no you guys have it all wrong. The Flying Spaghetti Monster reached down his noodley appendage and created a Mountain, Trees and a Midget. This ape business are lies spread by the non-FSM Believers. They shall never know what heaven is like, with it's stripper factory and beer volcano!
Life would still have the potential to exist elsewhere, but would have to adapt to a different environment.
This is a fairly common theory (especially in the wake of the early findings that the other planets in the Solar System are uninhabitable by humans), but our studies of our own solar system suggest it to be untrue. If life were as adaptable as suggested, then we'd find inflatable beings on Jupiter, Crystaline entities on Venus, creepy crawlers on Mars, and other life forms well suited to their environment.
Yet no such creatures have ever been found. Hope is still held that water creatures may be found on Jupiter's Icy Moons (specifically Europa), but we've pretty much exhausted the remainder of the Solar System.
Turning back inward toward Earth, we can't find life in many combinations. Pretty much all life on Earth follows the pattern of Carbon-basis with DNA information storage. About the most extreme variations are the circulatory systems of animals, with some having Copper-based blood.
Some organisms are able to survive extreme conditions, but they tend to not actually thrive in such environments. There are no signs of life that has specifically adapted to survive in conditions equating that of the more extreme planets. Even the Silicon-based Lifeform theory suffers heavily from a lack of any known examples.
While we occupy only an insignificant portion of the universe, our best evidence to date suggests that we may be far more alone than we might have hoped.
P.S. The Wikipedia article on The Fermi Paradox goes over many of these points in detail.
I once read an interesting story about some astonomer who believed that a long time ago Mars' orbit once was highly eliptical and crossed Earth's orbit and there was a near collision. Mars used to have oceans that alternatively froze solid and melted & boiled during it's highly elliptical orbit around the Sun until a very close encounter with Earth, where the two planets' gravities caused them to do a quick dance around each other during the near-collision, slinging off most of Mars' water which then was captured by the Earth's gravity and eventually fell into our own oceans, then Mars itself got slung outward towards it's current orbit where it collided with another small planetoid, the collision resulting in the formation of the asteroid belt and Mars' current stable orbit that is vastly less eliptical that before, but still not "almost circular" like Earth's orbit..
Nah. Eve was faking it.
This is a fairly common theory (especially in the wake of the early findings that the other planets in the Solar System are uninhabitable by humans), but our studies of our own solar system suggest it to be untrue. If life were as adaptable as suggested, then we'd find inflatable beings on Jupiter, Crystaline entities on Venus, creepy crawlers on Mars, and other life forms well suited to their environment.
Yet no such creatures have ever been found. Hope is still held that water creatures may be found on Jupiter's Icy Moons (specifically Europa), but we've pretty much exhausted the remainder of the Solar System.
I'm going to have to argue with that. To be perfectly honest with ourselves, we can't say whether life only exists on a physical plane, or a mixture of magnetic, physical, spritual, gaseous.. we have no idea. It could be that life is abundant in forms we just haven't had the opportunity (capability) to discover yet. When one looks at areas that now seem unihabited, it seems impossible that they ever were. At present, desert covers a large part of Australia, The Great Sandy Desert, The Gibson Desert and the Great Victoria Desert combine to fill more than half of Western Australia. It was covered by large sheets of ice before that, and before that by a shallow ocean, which was most defintely teeming with life. The south pole has produced palm tree fossils. To a temporary observer (as we are to the celestial bodies), the south pole seems dead. it was once covered in life. Things change, things move, and accidents happen. Just because our sister and brother planets look devoid of life now, doesn't mean they are or have been. Or will be for that matter.
** "It's not my job to stand between the people talking to me, and the ones listening to me." -- Pego the Jerk
There are just so many little things about the Earth that are balanced in favor of life (e.g. Distance from Sun, size of star, size of planet/gravity, magnetic field strength, atmosphere composition, etc.)
The distance from the sun, is not as important as it seems to be. The habitable zone has not been at 1AU at all times and it's going to change again in the future. There was a time when Mars was in the habitable zone and Earth was not. Similarly, when the sun will get older and on its way of becoming a red giant, Mars will again be in the habitable zone while Earth will be as hot as Venus.
The size of a planet and its gravity doesn't necessarily favor or hinder the development of life, as long as you don't take the extremes into account(ie. life would most likely not develop on an asteroid or a gas giant, though there could be exceptions). Mars is a small rocky planet with a gravity of 0.376 Gs which is quite low for humans. But that doesn't mean life didn't exist there. Earth's 1G is not some kind of universal standard for life. It's just the gravity, earth species live on. The same goes for atmospheric composition and magnetic field strenght. It's the enviroment we evolved and live in, not a universal standard. Humans would have as hard a time adapting to a lower/higher G enviroment, or to a deviant atmospheric composition, as a lifeform from somewhere else would have on Earth.
Also don't forget evolution. Life can adapt to a changing enviroment. If we send humans to live on Mars, after several generations, their successors won't be able to live on Earth's gravity. Which btw I think it's the key for colonization of other planets. If we ever find a way to accelerate evolution changes on ourselves, it'd be easier to do this instead of terraforming other planets.
VStrider.
To me, the best evidence for water is this map, which they always show at NASA presentations on Mars. It's a topographic map colored by altitude, and you see that the areas below a certain depth are almost completely crater-free, contrasted strongly with the areas above that depth. This, to me, is a really, really strong argument that it was once covered in water and had a coastline.
Looking at that map always makes an Earth-like Mars seem much more real to me.
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Mars' atmosphere is drastically thinner than ours, and that is assumed to be in a large part due to the smaller size. The gravitational pull simply can't maintain a thick atmosphere, and Mars' size is such that the core has cooled off, and techtonic activity has stopped. Lack of techtonic activity means that atmospheric gasses are no longer being replenished. It may be possible that life could exist without an atmosphere, but it seems very unlikely to me. There would at least need to be a liquid medium to distribute metabolic chemicals (such as CO2 and O2 on earth) to allow for life to have the proper energy to survive. On Mars this would have to be on the surface, as the lack of techtonic activity means there would be no thermal vents such as on earth which provide another chemical gradient which allows some forms of life to survive. I don't have a problem seeing that life could have existed at one time on mars, but I highly doubt that it is currently there. There may be some remnant organisms in deep deep stasis which are basically waiting for favorable conditions to revive, but I personally do not call that currently living.
I'll never make that mistake again, reading the experts' opinions. - Feynman
Hmmm, maybe Mars was Earth version 1. Then the designer addressed the defects and came out with version 2.
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