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Space Science

New Map Hints At Venus' Wet, Volcanic Past 118

Matt_dk writes with this excerpt from Space Fellowship: "Venus Express has charted the first map of Venus' southern hemisphere at infrared wavelengths. The new map hints that our neighbouring world may once have been more Earth-like, with a plate tectonics system and an ocean of water. The map comprises over a thousand individual images, recorded between May 2006 and December 2007. Because Venus is covered in clouds, normal cameras cannot see the surface, but Venus Express used a particular infrared wavelength that can see through them."
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New Map Hints At Venus' Wet, Volcanic Past

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  • by Anonymous Coward

    Venus... Wet... Volcanic... - sounds like the perfect title for some strange alien porn :-)

  • crap... (Score:5, Funny)

    by Anonymous Coward on Tuesday July 14, 2009 @09:10AM (#28690569)

    That title would have been so much better if it was:

    "Infrared Scan Of Venus' Southern Regions Hints At Wet, Hot Past"

  • The new map hints that our neighbouring world may once have been more Earth-like, with a plate tectonics system and an ocean of water.

    Yep. Until the Venusians burned all those fossil fuels and released all that CO2....

    • Re: (Score:3, Funny)

      by wjousts ( 1529427 )

      Damn you Mekon! [wikipedia.org].

    • by jameskojiro ( 705701 ) on Tuesday July 14, 2009 @09:26AM (#28690765) Journal

      No, I blame the people who didn't want to burn greenhouse gases who pushed everyone to use renewable sources like "Geo-thermal" or "Venu-Thermal" energy that caused plate tectonics to grind to a halt and the outer crust to solidify and thicken which was all well and good until a few hundred million years later all of that internal Venusian heat had to go somewhere and lo and behold instant planet wide resurfacing and extreme out gassing.

      The Eco-nuts of Venus were all proud of their renewable energy plan for geothermal until the fateful day the surface of the planet melted and they were all screwed. Thanks eco-nuts!!! Now there is one less habitable planet in the solar system! Too bad all of the amazon Venusian Women melted in the great planetary resurfacing 500 million years ago.

  • When I read that title, I thought of the mythological Venus, not the planet. SCNR.
  • Does molten rock really mean there has to be a volcano? The thermal map shows that some parts get up to 715 K, hot enough to melt lead.
  • Plate tectonics stopped on venus long ago and this lead to overheating which caused a massive planet wide resurfacing and out gassing ever few hundred million years, causing venus to be the craphole it is now. If it had a moon and decent rotation plate techtonics would have likely been persevered. and life may still have been there.

    • by paleo2002 ( 1079697 ) on Tuesday July 14, 2009 @09:44AM (#28691047)
      Planetary rotation and the presence of moons has nothing to do with plate tectonics. The moon's gravity isn't strong enough to move whole sections of the planet's crust. The direction of plate motion varies from place to place and over time. If it were affected by the Earth's rotation, plates would only move CCW or CW. Plate motion on Earth is powered by mantle convection - magma from the lower mantle rising towards the surface, cooling, sinking back down, heating up, rising, etc. The recycling of magma essentially drags the plates around, like a conveyor belt.

      Venus has a kind of tectonic cycle, but it works much differently. Based on the presence and relative age of craters and volcanoes on the surface, Venus seems to undergo catastrophic, global volcanism every 500Ma. This massive periodic volcanism, among other things, replenishes the planet's super-thick CO2 atmosphere. Otherwise, solar winds would have long ago stripped Venus of its atmosphere, since the planet has no significant magnetosphere.
      • Very nice description. However, Earth's plate tectonics can affect the rate of recession of the Moon. The configuration of the continents controls the size of the ocean basins, which in turn controls how dissipative the Earth is. The dissipation rate controls how quickly angular momentum is transferred from the Earth's rotation to the Moon's mean motion. As the moon gets more angular momentum, it moves away from the Earth.

        That said, I agree with your post. I just thought this was a neat, if only tan
        • I've never heard that one before. I know that tidal forces are slowing down the Earth-Moon system's rotation and are causing the Moon to drift farther from the Earth. But, it makes sense that the distribution of ocean water would impart some variability to the equation. I wonder if the Tharsis Bulge on Mars has similar effects . . .

          You know, I always tell my students (I'm an earth science professor at a community college in NYC) that Plate Tectonics explains everything on Earth. This is another great ex
    • Assuming life was able to start there in the first place (and given large amounts of water and the right temperature, it seems possible it could had). Organisms that thrived on excess CO2 and helped trapped excess CO2 should have flourished and helped regulate the atmosphere.
      • Gaia Theory, as I learned it back in college, is simply a way of expressing the variety of organic/inorganic cycles that mediate conditions on a planet. The carbon cycle is an excellent example of this. Photosynthetic plankton absorb CO2 from the atmosphere, die, and eventually become seafloor sediment. That carbonate rock is eventually subducted into the lower mantle where it melts and fuels volcanic eruptions, rereleasing the CO2 into the atmosphere. Long-term changes in plankton populations can lead
        • You misread what I wrote. Based on the parent I responded to, my reply is based on the assumption that life was present before the runaway CO2 cycle.

          Which, if assumed, would be an issue for Gaia theory since the self regulation of conditions favorable for life did obviously not occur. Obviously there are circumstances that one could assume that Gaia couldn't overcome. But on such long timescales, it would be a dent in the armor of Gaia.
  • Why is that so many people who dream of colonizing other worlds and traveling faster than light rarely leave their own houses?

    • Re: (Score:1, Funny)

      by Anonymous Coward

      because interplanetary travel comes at the cost of being confined to a small space?

    • Re: (Score:3, Interesting)

      I am actually curious to see how this ends up getting modded. Troll? Funny? Insightful. My secret wish is for +5 Troll.

      • It needs this response, though:

        Why is that so many people who dream of colonizing other worlds and traveling faster than light rarely leave their parents' basement?

        There, fixed that for you.

    • it's because everyone thinks they are weird...and they know it.

      -Oz
    • by martas ( 1439879 )
      well, it's an all or nothing attitude. if i can't walk in a park that's on a planet on the other side of the galaxy, then i wont walk in any park at all!
    • by MBGMorden ( 803437 ) on Tuesday July 14, 2009 @11:06AM (#28692159)

      For the same reason people who think for sure they'd be a part of Star Fleet if it existed very rarely join the military.

      Most people who dream of flying a star ship will never go about taking up flying the planes that we DO have available to us.

      Most people who cheer on the Rebels in Star Wars would never ever think of taking up arms against a hostile government.

      All in all, a lot of people are dreamers rather than actual doers. As a person who still is a fan of Sci-fi - your sentiment is one that I realized myself a while back, and I've personally chosen to make an active attempt to enjoy and accept the time I live in, and the technology available to me. While fun in it's own way, if all you do is look wishfully towards a future that we'll never see (and likely won't quite materialize the way we envision it anyways), then life gets kind of boring after a while.

      • For the same reason people who think for sure they'd be a part of Star Fleet if it existed very rarely join the military.

        In the Star Trek universe, Star Fleet is the only organization that does anything interesting. Colonists are basically cannon fodder. Corporations are corrupt. Any scientific research is either driven by Star Fleet or megalomaniac/corrupt scientists (or both). It doesn't leave much choice.

      • For the same reason people who think for sure they'd be a part of Star Fleet if it existed very rarely join the military. [...] All in all, a lot of people are dreamers rather than actual doers.

        No, that's a bunch of shit. The fictional Enterprise is on a mission of peaceful exploration, trying to help people. That's not what the U.S. military does! Helping people only happens when it supports some concrete goal, take a look at history if you aren't in line with that one. I don't join the military because I don't want to support American imperialism. I would join something like Starfleet, for obvious reasons.

        I think you're projecting.

        Most people who cheer on the Rebels in Star Wars would never ever think of taking up arms against a hostile government.

        Most people wouldn't recognize a hostile government if it shot th

      • Maybe it's because the rebels in Star Wars are fighting in wars that are worth fighting. When we have one, I'll do my part to help.
    • That's an easy one...

      Because we still waste too much money fighting each other over whose god has the biggest dick, and too little of those resources into getting ourselves off this planet and ensuring the survival of our ecology?

      The day the human race grows up and learns that it's real enemy is the universe - entropy - will be the day that we climb out of the cradle and learn what it means to grow up.

      Not likely any of us mortals at this point in time will see it.

      SB

  • but i always thought venus was a better target for terraforming

    its easier to subtract out of venus' atmosphere than put in mars' atmosphere what isn't there. i didn't say EASY, i said EASIER

    some sort of genetically engineered bug that sequesters all of the CO2 and H2SO4, and permanently precipitates it out, preferably leaving O2 and H2O. something that could live on top of the clouds and in them. there's a lot of energy in that atmosphere, and you're closer to the sun... which is actually good: something to work with. rather than being far from the sun and feeble with resources, like mars

    again, this is in no way easy, but if we ever reach the technological acumen and sustained effort needed to terraform one of our neighbors, i really think venus is a much better target than mars. more available energy to work with, almost identical gravity profile, and the need to subtract something out of the atmosphere, rather than to somehow create what isn't there, which is a lot easier to do, logically

    mars has a long and sustained following and fan base, in science fiction as well as real science, but venus is the real future of mankind's first off-world colonization (besides the moon), if we ever get to that level of sophistication to even consider the possibility

    • by Ihlosi ( 895663 )

      there's a lot of energy in that atmosphere,

      A lot of energy doesn't help one bit if you can't turn it into a useful form.

      In fact, many of our present ways of generating energy would work much better in really cold places due to a higher temperature difference to work with.

      and you're closer to the sun... which is actually good: something to work with.

      I hope you're bringing sunscreen with SPF measured in powers of ten.

      • don't depend on temperature differences. the only difference between hypothetical terraforming bug #1, functioning at high temp, versus hypothetical terraforming bug #2, functioning at low temp, is that bug #1 will work orders of magnitude faster than bug #2. regardless, we're not going to be terraforming with industrial sized reactors that do depend upon temp differences, but with nanotech, or more likely, genetically engineered critters

        furthermore, suncreen with high SPF is the least of your concerns. wit

    • The problem with Venus is that it is closer to the sun. Even if you converted Venus into Earth 2.0 it would almost certainly be too hot to live on. This means that you would need some way to cool the planet significantly as well as shield it better from the increased UV radiation. Not impossible but I'm not so sure it is a better target than Mars. The advantage of Mars is that you can build structures on the surface as a step towards terraforming and build up the process gradually. This is close to impossib
      • where the temperature is regularly 115 degrees. they do it by just not going outdoors that much and having good ac. so you live indoors on venus, and you have genetically engineered crops that can withstand the high temps and scorching rays (as well as cosmic rays and other nasty high energy rays, since venus has no geomagnetism). you could have some nice architecture with large bay windows, just no skylights ;-P

        now compare that limitation with mars, with the very low atmospheric pressure, the much lower gr

        • by Ponga ( 934481 )
          In that case, I motion then that the people of Phoenix be the first to colonize Venus... seriously, you all will feel right at home!
        • so you live indoors on venus, and you have genetically engineered crops that can withstand the high temps and scorching rays (as well as cosmic rays and other nasty high energy rays, since venus has no geomagnetism).

          I'm not sure if you're kidding, so if you were, just ignore this, but Venus' surface temperature hovers around 460 degrees Celsuis. I don't think genetic engineering is going to create crops that will withstand being scorched to a black smudge in seconds.

          Also, the atmosphere is over 80% CO2, wh

        • by Ihlosi ( 895663 )
          now compare that limitation with mars, with the very low atmospheric pressure, the much lower gravity, and the bitter cold.

          Heating something is much easier than cooling it, in most cases. Heck, as soon as you start generating serious power, you'll have plenty of waste heat.

          you would need a moonsuit to go outside on mars, even a terraformed one, unless you figured out some magical way to bulk up the atmosphere.

          Magically bulking up Mars' atmosphere is probably much, much easier than magically bulking

        • Lets compare scientifically. We cannot use the actual temperature of Venus since this is dominated by the greenhouse effect of the atmosphere so lets use radiation. The mean distance of Venus to the sun is 108M km vs. 146M km for Earth so Venus will receive 1.83 times the radiation from the sun (1/r^2). We can assume that it radiates the sun's energy at the same rate (i.e. assume equilibrium) so using Stefan's law we see that the radiation rate is proportional to T^4 (where T is in Kelvin). Hence if Venus
    • Actually from many things I have seen, Mars would actually be easier to terraform, but I have always thought that Venus had more long term potential. A couple of years ago I saw a suggestion of a system to terraform Mars that is within our current technological capability. The article ran all of the numbers and it would work. The basic idea was that you find an ice asteroid or two and crash them into Mars. This would provide the missing water and help increase the density of the atmosphere (it has been long
    • by martas ( 1439879 )
      unfortunately it also means that in the event of some freaky sun-related incident like a giant solar flare, electronic devices on venus will be fried way easier than anything on earth, or especially mars. (although maybe i'm wrong about the mars part. after all, it doesn't have a humongous magnetic field protecting it...)
    • by Sparklepony ( 1088131 ) on Tuesday July 14, 2009 @10:58AM (#28692045)

      but i always thought venus was a better target for terraforming. its easier to subtract out of venus' atmosphere than put in mars' atmosphere what isn't there. i didn't say EASY, i said EASIER. some sort of genetically engineered bug that sequesters all of the CO2 and H2SO4, and permanently precipitates it out, preferably leaving O2 and H2O. something that could live on top of the clouds and in them.

      Actually, no, it's way harder to terraform Venus than it is to terraform Mars. The "just introduce algae" idea was proposed in 1961 by Carl Sagan, before the full extent of just how awful Venus' atmosphere was was fully appreciated. Venus has 90 atmospheres worth of carbon dioxide, and pretty much no available hydrogen. If you want to convert carbon into organic molecules, you need to have hydrogen - carbon alone is not sufficient. But if by some chance you did somehow convert 90 atmospheres worth of carbon dioxide into carbon and oxygen, what you'd wind up with is a furnace-hot planet with 60 atmospheres of pure oxygen and a layer of flammable carbon several hundred feet thick. This is not a stable situation, it'll go right back to the way it is now very quickly and spectacularly (though since the carbon would have been burning as fast as it's produced you'd never get such an extreme disequilibrium in real life). The permanent sequestration of all that carbon dioxide will require the addition of more material to the planet's atmosphere from the outside than would be required to give Mars a whole new atmosphere from scratch.

      Furthermore, once you've given Venus an Earthlike atmosphere, there's another issue to consider; Venus has a rotation that's 243 Earth days long. Night lasts for 122 days on Venus. Without its ultra-dense atmosphere to convey heat around it's going to get extremely cold in the dark. We'll have to come up with a whole new ecology to endure those conditions and it doesn't sound all that fun for human inhabitants.

      • Or we'd have to do something at least as difficult as adding an atmosphere to Mars, slam asteroids into Venus in exactly the right way to speed up its rotation. FYI, a martian day is already quite close in length to an Earth day.

        The whole completely replacing the crust every half billion years that theorized to happen on Venus is a bit of an inconvenience as well.

      • wrong (Score:3, Interesting)

        if you actually converted venus's atmosphere to something approximating earth's, it wouldn't be as hot anymore. right now, venus is the same temp, pole to equator, night to day. but reduced, the atmosphere would be like living in the desert, you'd have very cold nights, and very hot days. and since a day on venus is 100 days long, it means you'd have a siesta culture where everyone stays inside midday, and inside midnight. dawn and dusk would be pleasant in between, and dawn and dusk would last weeks. ecolo

        • as for your unstable balance of o2 and carbon, thats pretty much earth, right now. i can walk into most any nonwater environment on earth and start an inferno by myself if i wanted to. and yet our biosphere has lasted a plenty long time, mainly because the biosphere maintains the balance. it would be maintained biologically the same way on venus

          I think you're underestimating the magnitude of the difference here, and just how reactive that much pure oxygen would be. The Apollo 1 fire happened because the

          • i said it would EASIER than terraforming mars

            with mars, you're faced with the problem of making an atmosphere where there isn't any. that seems like a harder problem than getting a high oxygen atmosphere to behave. you talk about bombarding venus with alkali metals or calling up lando calrissian: these seems way harder to me

            " Photosynthetic life might help maintain a livable environment after you've made it livable, but it's not going to get there by itself - no way no how"

            absolutely opposite that statement

            • with mars, you're faced with the problem of making an atmosphere where there isn't any

              There is a vast amount of CO2 absorbed into the rock and soil on Mars. If you raised the temperature a little some of that would come out. As the absorbed CO2 was released the green house effect would increase and even more would be released. The cycle would continue until all the CO2 was released and an air pressure that you could survive without a space suit would be available.

  • There seem to be a high percentage of historically "Wet" satellites in our solar system. Earth,Venus, Mars possibly Europa, Titan....... Are our assumptions about solar system formation and the likely hood of liquid water covered satellites off?
    • by Anonymous Coward

      Indeed, it seems our planet is situated in the middle of a graveyard. Could it be that the "wet phase", many / all rocky planets seem to go through (our current one on Earth has lasted about 4 billion years) is just temporary? Is the Earth an exception to this rule, in that it seems to have achieved stability, or will we eventually dry up as well?

      I guess it's like emptying a bag full of coins on the floor from a height. The will bounce and flip and spin, but eventually they will all settle either on heads (

  • but dry present is discouraging.
  • ...and the submission's title.

    There's a joke here. I just know it...

    Think... think... think....

    Nope, can't think of one.

  • Bradbury was right about the wet part at least [wikipedia.org]!
  • You got me, I wasn't trying to saying Venus didn't have an atmosphere, but its lighter gases (Hydrodren, Helium, Oxygen were all burned and or pull off) do to its close proximity to the sun. Leaving it with the dense gases which it is currently made of (Nitrogen and Carbon dioxide..maybe a little methane, but don't quote me I haven't taken an atronomy class since freshman year of college). So sorry in forgetting to say part of.
  • That technology using some particular wavelength of IT to see through? Do they have any plans to incorporate them into sun glasses?
  • I wonder how many people will get fired as a result of reading this article, and then googling for "wet venus" at work, and getting NSFW results.

  • by 2names ( 531755 ) on Tuesday July 14, 2009 @10:02AM (#28691261)
    42. It's everywhere!
  • If this is true, Venus is now the number one planet to study. If it started out to be that much more Earthlike than we had previouly figured out to be than we need to know what happened to turn a potential Twin Earth to Hell. And is Earth going towards the same route and how much may Humanity have to say about it one way or the other? Why is it's rotation so slow? (Little known factiod, the extra weird thing about Venus' rotation is that it is locked to Earth in that whenever it is at closest approach to
  • Further down, if you would like to look, but I meant to say part of its atmosphere, which include the lighter elements of Oxygen, Helium, and Hydrogen. This left the denser elements which it consists of now(Nitrogen and Carbon dioxide.)
  • I have always thought that if Venus had formed in Mars orbit, we would likely have a true second Earth in our solar system. It would have been able to retain surface water. It would have a significant atmosphere. What its atmosphere would be like, I don't have the expertise to hypothesize, but it would have evolved far differently than the current Venusian atmosphere.

    The highest temperature ever recorded on Mars is 70F / 21C. With an atmosphere and the greenhouse effect, a Venus in Mars orbit would be si

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