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ESA to Send Spacecraft to Venus
teeto writes to tell us The International Herald Tribune is reporting that the European Space Agency is planning to send a spacecraft to peer at Venus." From the article: "If the robot craft pulls off the complex maneuver of slowing down enough to swing into orbit, scientists hope it will help solve the mystery of how the shrouded, churning atmosphere of Venus formed and how it maintains the planet's broiler-like temperatures."
Venus once had a thriving civilization, much like Earth, but they burned their fossil fuels and ruined their environment. DON'T BE LIKE VENUS!
"ESA to Send Spacecraft to Venus"? They already did, Venus Express launched on 2006-11-09, it arives at Veuns on Tuesday.
Is this article a bit late?
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See here:
http://sci.esa.int/science-e/www/area/index.cfm?f
The thing is due to achieve orbit in a few days.
Cloned foods give the statement "We had that last week!" a whole new meaning.
I just think that'd be incredible. Until everything melted.
Don't Hate, Gestate
Now that's some good engineering!
Don't Hate, Gestate
This AC comment seems to have been made in jest, but it got me thinking.
... )
Do we have any way of knowing how long Venus has been a runaway greenhouse? (That phrase, by the way, invokes a really bizarre mental image
Is it conceivable that the climate there went haywire within human history? Given the current pressure, temperature, and chemical composition of the atmosphere on Venus, is there any chance that any indications at all could have survived of a possible former ecosystem there?
Mars is fascinating for what it might have become. Venus is fascinating for what it might have been.
How can a post be modded "overrated" or "underrated" when it hasn't been rated yet?
At least the ESA can probably convert from old timey to scientific measurements properly.
<Mission control> Spacecraft 1, you are currently 1300 rods from impact, at a fuel consumption rate of 4 7/16 hogshead per mile. Be advised.
<Spacecraft> WTF?!
Poor planet, can't people leave it alone. It's just minding its own business and here come some dudes probing it. Would you want that, your just bumming around and whamo! probe to the ass in the name of science.
Stop planet Abuse now!
Check out http://www.mentallandscape.com/V_Venus.htm for an excellent archive of the Soviet exploration of Venus.
Venera 9 sent image telemetry for 50 minutes. It scanned 174 of the panorama from left to right, and then 124 scanning right to left.
They drilled, photographed, and used penetrometers on the surface. Each mission lasts a few hours to days before the atmosphere crumples the spacecraft like a soda can due to the pressure. Much different than life on Mars!
Space and Computers.
Do we have any way of knowing how long Venus has been a runaway greenhouse? (That phrase, by the way, invokes a really bizarre mental image ... )
Almost from the get go. From what I've read, Venus has simply way, way too much Carbon Dioxide. Carl Sagan's romantic plan of seeding Venus with bacteria to eat up the CO2 simply fails because there is way too much CO2. To get Venus straightened out for human habitation, you would have flat out get rid of something like 89 parts out of 90 in the Venutian atmosphere, and there's really no place to put that much air. There've been some proposals to freeze it into giant CO2 chunks and launch them into space, or, slam some kind of an asteroid or even planet into Venus to jack the air into space, but both are so far beyond our technology as to be unimaginable. There's also not enough of other gasses in Venus's atmosphere - you really need a lot of nitrogen or something like it, like, well, the Earth has.
Then again, the Earth has an aweful of lot of Carbon Dioxide in the oceans and the limestone.... maybe we could all be doomed.
Is it conceivable that the climate there went haywire within human history? Given the current pressure, temperature, and chemical composition of the atmosphere on Venus, is there any chance that any indications at all could have survived of a possible former ecosystem there?
Well, there's one famous Internet crackpot that swears he sees Zeppelins on Venus and there are people there...and NASA is covering it up. But, outside of that, I think Venus has always been dead. Venus has a lot of problems even besides the grueling atmosphere. It has a long rotational period and lacks a magnetosphere.
As far as the earth goes, the most spectacular environment catastrophe posited is Snowball Earth. Basically, the entire Earth was frozen over with a sheet of ice two miles thick, everything died and there was no oxygen in the atmosphere, for a period of a few hundred million years. It was a rough time, but, ironically, the Earth was saved by an accumulation of 350 times our present level of CO2.
What's really interesting about Earth's past is that the atmospheric composition has varied rather wildly. It is not at all automatic that we have 78% nitrogen, 20% oxygen and then some other gasses. I have no idea how they infer atmosphere, but it must have something to do with chemicals found in rocks and knowledge of how those chemicals must have been made, coupled with radioactive dating. Incidentally, the overall portion of CO2 in the air is rather small, something like 0.04% (and going up). For all the talk about whether the CO2 is manmade or not, or whether it causes global warming, some facts are most certainly known. First, the CO2 level has doubled in a 100 years, and when a planet wide change happens that fast, you really do have to have cause for concern. All sorts of questions need to be asked, but the big one is, is the rate of doubling changing? Like, will we double it again in 50 years, then 25 again, and so on? I think we only need to double the atmosphere not too many times before we all die.
This is my sig.
Venus rotates on it's axis once every 243 Earth days. One Venusian day (sunrise to sunrise) is 117 Earth days. It also gets a hell of a lot more radiation than the Earth.
My guess, if it had oceans, the 59 days of straight sunlight would cause them to boil away. With the oceans gone, the surface would bake and scorch sending more gases into the air.
http://www.sunspiritgallery.com/images/venus.jpg
"Forgive us our trespasses, as we forgive those who trespass against us." -Jesus Christ The Lord's Prayer
Wouldn't it be wild if we'd come to earth hundreds of thousands of years ago from Venus, seeded only by "Adam and Eve" who were a bit like breeding Superman(s), while the Venusian civilization died, and the one on Earth began to rebuild from scratch?
Wild, dude. BTW, pass that bong to me when you're done with it....
sig has been sent away for a few small repairs...
The Discovery Science channel is running a special, "Venus Unveiled", about the planet and this ESA program. It airs several times during the next 2 weeks.
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http://science.discovery.com/tvlistings/episode.j
Whenever the offence inspires less horror than the punishment, the rigour of penal law is obliged to give way...
Heh, you've attracted a lot of replies and nobody's yet hit the right answer.
Propose your choice of terraforming technique. Convert one chemical into another, physically remove the atmosphere, don't care which you choose, really.
Now, compute the energy requirements of your terraforming action.
Then you shall achieve enlightenment.
In short, terraforming Mars for a geologically brief period of time is on the tantalizing edge of feasibility, because a lot of it would involve slightly nudging comets and such to hit Mars. That's a net gravitational energy reduction, and we might be able to manage that. Even so, it might not work; I think it far more likely you'd have to build enclosed settlements, or perhaps even more likely, modify life forms to live on Mars basically as it is, possibly with some resources augmented by the aforementioned comets. But to get from Venus as it is, to a Venus we could walk on, would take an astronomical amount of energy no matter how you slice it. (A rather small "astronomical" amount of energy as such things go, but "astronomical" nonetheless.) It's one of those things that by the time we can do it, we'll probably have better uses for that sort of energy.
By the way, I'm actually-factually talking about energy states, in the technical thermodynamic sense. It's not a matter of waiting for "science" to wave a magic wand; any 'science' that can re-write the laws of thermodynamics is well beyond anything we can speculate about. Conservation laws are about the strongest physics results we have.
You make a good argument, but I'd like to add a qualification. I'm not sure the availability of energy itself is a problem with Venus. More than enough energy for any conceivable terraforming rains down on Venus from the Sun. And it's quite usable energy, since its temperature is close to that of the solar photosphere (5500K). Thermodynamically speaking, you can run some very efficient heat engines between a hot reservoir at 5500K and a cold reservoir at even the high temperatures of Venus (300-700K, depending on altitude).
So the energy is there. But it isn't necessarily easy to use. The only plausible scenario probably remains some kind of biological seeding, i.e. designing some kind of photosynthesizing microbial life that can suck up all that CO2 and convert it to carbonate rock, as such life is thought to have done in the early history of the Earth, which is where our CO2 went and why we have great beds of limestone in the crust.
But I believe the problem with this is that there is very little water in the Venusian atmosphere, and all the microbial life we know about needs water. Furthermore, such a seeding process would not be quick -- at a minimum, millions of years are necessary -- and it might be hard to put the brakes on at the end.
"As far as I am aware, we know a lot less about the surface of Venus than we do about the surface of Mars or say, Mercury, or even Pluto."
Since the Magellan probe (which someone else already pointed you to), we've known more about the surface of Venus than we have about the Earth (oceans get in the way). Mars has been similarly mapped within the past decade or so, thanks to various orbiters. Mercury is something of the bastard child of the inner solar system; there's a probe on the way now, but the best we have is from a Mariner 10 fly-by that photographed most of one side of the planet before most of us were born.
Pluto... we're not even all that sure there is a "surface," at least for half of its orbit.
The reason for needing this kind of effort to cool the Space Station, even thought it's in the "very cold" environment of space, is that while the temperature of space is very low, the thermal capacity of space is also very low. That is, there's just very, very little of any cold matter around to which you can transfer heat, the way your body transfers heat to winter air when you step outside in December. You can radiate heat as infrared radiation, of course, but to be efficient this requires a lot of surface area for the volume being cooled. And yet, of course, when you build spaceships you tend to want to minimize the surface area for a given volume -- i.e. build compact shapes.
Furthermore, in space the wretched Sun is radiating huge gobs of light and heat at you 24 hours a day. Got to get rid of that, too.
The Soviets sent probes to Venus a while back and retured pictures. Color pictures in the visible spectrum.
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It has a horizon and due to the extreme fisheye it is perhaps difficult to tell just how far the horizon is, but it appears to be perhaps 10 meters or a bit more.
http://www.mentallandscape.com/V_DigitalImages.ht
http://lkml.org/lkml/2005/8/20/95
Uh, if the men are from Mars and the women from Venus, how did they end up here on Earth? Possibly each was sent here by whoever else lives on Mars and Venus, respectively.
Apparently we humans are rejects from two worlds...