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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."
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
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!
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.
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.
xkcd.com - a webcomic of mathematics, love, and language.
Hmmm, maybe Mars was Earth version 1. Then the designer addressed the defects and came out with version 2.
The more you regulate a company, the worse its products become.