Posted on 05/26/2004 9:09:24 AM PDT by presidio9
There could be life on the planet Venus, US scientists have concluded in a report in the journal Astrobiology. The existence of life on the planet's oven-hot surface is unimaginable.
But microbes could survive and reproduce, experts say, floating in the thick, cloudy atmosphere, protected by a sunscreen of sulphur compounds.
Scientists have even submitted a proposal for a Nasa space mission to sample the clouds and attempt to return any presumed Venusians to Earth.
"Venus is really a hellish place," said Professor Andrew Ingersoll, of the California Institute of Technology.
"If you could get through the sulphuric acid clouds down to the surface of Venus you'd find it was hotter than an oven. You could melt lead at the surface of Venus and there'd be no water."
But it was not always like that. Earth and Venus are in many ways sister planets.
"Current theories suggest that Venus and the Earth may have started out alike. There might have been a lot of water on Venus and there might have been a lot of carbon dioxide on Earth," Professor Ingersoll explained.
But all that was to change. On Earth, life in the oceans took in carbon dioxide and turned it into limestone. On Venus, 30% closer to the Sun, any oceans boiled away and the water vapour added to the runaway greenhouse effect.
Venus became our planet's ugly sister. Its make-over, which occurred billions of years ago, has left a surface where the pressure is crushing.
Arrested development
But, according to Louis Irwin of the University of Texas at El Paso, the changes on Venus may have been slow. "It may well have been Earth-like long enough for life to either emerge or be transported there," he said.
Once established, life would have adapted to every environment, just as it did on Earth.
Two years ago, Austrian scientists discovered bacteria living and reproducing within clouds on Earth. The same could have been true on Venus. Then, as the surface became hot and dry, the clouds might have become life's only refuge.
The Venusian clouds are high in the atmosphere, where the temperature and pressure are quite Earth-like. There is even water present, though it is in the form of concentrated sulphuric acid.
But we now know of organisms that thrive in very acidic environments on Earth.
"If you think about what life needs in a broad sense then the clouds of Venus might actually be a habitat where something could live," explained David Grinspoon, of the South West Research Institute in Colorado.
Another problem could be UV radiation from the Sun. But Dirk Shulze-Makuch, also at El Paso, thinks Venusian bacteria could make use of a natural chemical sunscreen there.
"When we looked at the composition of the atmosphere, we thought that sulphur compounds are actually an ideal sun block for microbes."
David Grinspoon speculates that the organisms might even have evolved ways of making use of the UV, much like Earth plants use visible light for photosynthesis.
"One lifeform's deadly radiation may be another lifeform's lunch," he added.
But will we ever know if there is truth behind the speculation? Louis Irwin and his colleagues have a proposal in with the US space agency, Nasa.
"We would send a probe to Venus that would drop probably a collector tethered to a balloon-like floating spacecraft, it would collect samples of the cloud droplets and then blast off from the Venusian atmosphere for return eventually to Earth."
And what are the chances of finding live Venusians? David Grinspoon is in no doubt: "If they're there, I think we will find them eventually."
Screw Mars and Venus, We should be heading to Mercury
* The Craters at the poles are permanently shaded so you don't have the temperature extremes
* Mercury is about ½ the mass of Mars with less of an atmosphere so to blast off the surface would require less fuel.
* It's on average closer to Earth than Mars so you wouldn't have the total distance to and from as you would with Mars.
* Venus can give a boost both going and coming to Mercury(remember Venus boosted Cassini onto Saturn)
* There is Hydrogen and Oxygen in the atmosphere and surface of Mercury so you can make fuel, breathable air or water unlike Mars where you can't make any of those out of Rust.
* There is water ice in the craters near the poles so we wouldn't have to carry as much on the journey
* The Mining opportunities are limitless
* There is Helium in Mercury's atmosphere and in it's rocks (where there is most likely a lot) and unlike Earth's Helium the much of the Helium on Mercury is probably in the form of He³ which is supposedly a target fuel for (cold?)fusion.
The main problem with moving Mercury and Venus out to the temperate zone so they can be properly developed is that astrologers are not going to be able to pretend they even look at the sky anymore.
Another point in favor of off-planet habitats: better sex. Women don't sag. Men don't nead viagra. Once you go no-G you never go back.
Yes. Europa.
There could be life on the planet Venus.
I don't know, I guess it depends on the type parties they have?
I am aware of what Europa posseses, however, building a base there, to start, would be unbelievably difficult. Also, what would you mine, aside from ice?
In fact, we might as well just go with the whole Dyson sphere idea.
Since we can't agree on whether earth might be warming or not, and if it is whether our cooking fires have something to do with it, terraforming other planets seems a little beyond our means at this time. Moving planets is also beyond our means right now. We are far from having a permanently self-sustaining colony on Mars, even Antarctica is beyond our means. We couldn't even save ourselves if a 6 mile asteroid were spotted heading our way ten years out. Not impressive so far.
At any rate, all of this burned away and as their world "ended" - ours was just beginning.
older topic, perhaps different scientists:
Venus may sustain life, say scientists
The Telegraph (U.K.) | 09/26/2002 | David Derbyshire
Posted on 09/25/2002 6:30:44 PM PDT by Pokey78
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