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Hellish Vision of Mars Unveiled
mvladivostok writes "Yahoo has an interesting little article in which it is suggested that Mars may not have once been a warm, wet and hospitable planet that somehow lost its atmosphere; instead, it is suggested that the dead planet was occasionally bombarded by melting meteorites that carved out its distinctive craters and valleys. An interesting read."
It's got water, that would make future colonization that much easier/more feasible.
Question everything
From the article:
If earth is anything to go by, I thought evolution of self-reproducing organisms would require quite a few million years and a primordial soup...
Are you a grammar Nazi? I'm trying to improve my English; please correct my errors!
While it's certainly possible that Mars would have been bombarded this way, it doesn't appear likely for two reasons:
For one, there is no evidence of any other planetary body which would have gotten a significant infusion of water this way and it seems unlikely that Mars would have been the only target.
But the most important detail seems to be to just be a question of quantity. Regardless of maturity, in order for deep riverbeds such as appear on Mars to form you need a lot of water flowing for a fairly long time (years, not days). To get that water from impacts would mean that a LOT of such impacts need to have taken place over a (cosmologically) short period; which makes the first point above all the more noticable.
Even if Mars did get significant amounts of water this way (or had enough of it melted out by side effects) the water wouldn't have been around long enough to make geological constructs unless there was an atmosphere allowing it to remain liquid long enough to flow around for years.
I'm surprised someone at NASA would publish national-enquirer quality science like that. More likely, Yahoo misread the paper to extract the nice sounding bits.
-- MG
The same thing was happening on Earth. Earth gets smacked, life gets crushed, picks itself up, and tries again. Thankfully, life has yet to crush itself.
does rain precipitates differently in lower gravity? Certainly it would look a bit different hitting the ground, right? Maybe the Drops have to condensate bigger, so these giant raindrops come down at a half the speed of earths raindrops, like some boy-band video slow mo. Or maybe the raindrops are much smaller and it's a miniature version of earth rain. I wonder.
Okay, so the only currently relevant conclusion they are reaching is that life on Mars (if there is any) would have evolved to bloom and spread at massive speeds, like an even more extreme version of our desert plants. I can *kinda* see that since if there's usually no life in most places there's also no competition for anything that gets there. Given the Martian wind levels and a presumption of heavy rains then fast propagation is possible.
Thass nice. So what?
Well, it seems to me that if we begin to terraform Mars, or in fact, even build a base there that heats the surrounding area and spreads some moisture just by mistake, then we may get some sorta Martian kudzu spreading everywhere. Sounds fine to me.
Rustin
Data is the lever, rigor the fulcrum, brains the force that drives it all.
From the article:
The impacts would have injected steam into the atmosphere, both melted from the surface and from the asteroids and meteors themselves.
That is, they suggest the warm conditions you mention were created by steam and hot water. And the source of the water would not only be ice on the planet, but also from the meteors. The flooding and stormy rains that would follow would no doubt be able to shape the surface of the planet, creating all the valleys and such.
The first half billion years of earth were likely a molten meteorite hell too. Also most of the earths surface- the surfloors are recycled every 100-200 million years by plate tectonics, perhaps 20 times or so overall, wiping out much of the hellish scars.
Why do people who can't read keep getting modded as "insightful" here at /.?
>Doesnt anyone think we'd notice the pothole
>left by a 150 mile wide asteroid?
Please READ the article:
"Segura and colleagues used photographs of the Red Planet's surface and computer models to show that large asteroids or comets hit the planet 3.5 billion years ago."
That's 3.5 *billion* years. Almost any impact crater from 3.5 billion years ago on the surface of the Earth would have long ago been eroded away, uplifted by faults into mountains, or subducted down into the mantle. In any case, they'd be difficult or impossible to identify now. Very little of the Earth's surface from 3.5 billion years ago remains intact. On Mars, it's a completely different story.
There are a handful of large craters on Earth that are still identifiable after around 2 billion years, as this article makes clear. But the giants formed by large impactors from early in our solar system's history have long ago been erased (or at least thoroughly obscured) from the surface of this world.
Our moon on the other hand has plenty of gigantic impact scars left over from before 3.5 billion years ago. For example, the gigantic Imbrium crater on the lunar surface is around 700 miles in diameter, and was formed about 3.85 billion years ago. There are several lunar craters in excess of 500 miles in diameter. Our moon is also home to the largest known impact crater in the solar system, the colossal 1,300 mile wide South Pole-Aitken Basin.