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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."
I just think that'd be incredible. Until everything melted.
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?
I've been reading Slashdot for years and while there's always a ton of comments in the Mars articles about how great it would be terraform that planet, no one ever mentions doing so to Venus.
... why, after comparing the two planets, do people focus on Mars? I'm asking an honest question. From my perspective, Mars has so little to work with. Venus has plenty -- too much in fact. But think about it. Humans have proven themselves pretty good at destroying atmospheres. They're not so good at creating them. And in the case of Mars, you need to create an atmosphere. But in the case of Venus, you need to destroy it. Doesn't this make Venus a more natural candidate for human endeavours?
... can't you get water out of that somehow? Crank things up with some additional hardware, and if you pull enough material out of the atmosphere, you start to reduce surface pressure.
Why??
I look at the gravity situation and I really can't understand why people focus on Mars. Really. Does anyone ever look at the surface gravity of Mars before they start talking about terraforming it? It's only 38% of Earth's! (Compare that with freaking Mercury at 28%, or even the Moon at about 17%. ) What are your bones going to be doing in that environment after a few years?
But take a look at the surface gravity on Venus: it's 90% of Earth's.
Sure, you've got atmospheric pressures at the surface 90 times greater than on Earth. And the temperature averages 460 degrees Celsius. The atmosphere is about 96% carbon dioxide, and about 3% nitrogen. Then you've got trace amounts of sulfuric acid (tasty!), chlorine, and fluorine.
But seriously
Surely there's a chance that, with our slowly evolving understanding of organisms that survive around deep-sea volcanic vents, and our ever-evolving ability to tweak natural organisms, that we could devise some kind of bacteria that could thrive on Venus and start capturing the carbon from the atmosphere. There's so much for it to work with there. All that tasty carbon dioxide! And hey, H2SO4
And then there's that beautiful surface gravity.
Have I mentioned the surface gravity and how it's so close to that found here on Earth, unlike Mars?
I'm sure plenty of people far smarter than I ever will be have considered Venus and dismissed the idea after a few seconds of thought. But why? And why is Mars, with such wimpy gravity and such a scarce existing atmosphere given all the attention when it comes to dreams of terraforming?
Where's the love and the dreams for Venus?
Whoever designed level 61 in Frozen Bubble is a sadistic bastard.
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.
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.