The hellish climate of Venus may have arisen far more recently than previously supposed, suggests new research. If so, pleasant Earth-like conditions probably persisted for two billion years after the planet's birth - plenty of time for life to have developed.

Venus is virtually the same size as Earth and, on average, is our nearest neighbour. Today, its atmospheric temperatures are hot enough to melt lead and concentrated sulfuric acid continuously drizzles down from thick sulphurous clouds that completely block out the Sun.

But the planet once had a climate similar to Earth's and vast oceans of water. Planetary scientists agree that period ended when Venus lost its water due to a runaway greenhouse effect, but the question is when.

Until now, the best estimate, calculated 15 years ago by Jeffrey Kargel, of the US Geological Survey, was four billion years ago - just 600 million years after the Solar System's birth.

But new work by David Grinspoon, at the Southwest Research Institute in Boulder, Colorado, suggests the momentous transition may have occurred much later. He points out the Kargel's estimate was just a lower limit on when the change happened, because it did not include the effect of clouds in the Venusian atmosphere.

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I learned about this in Astronomy class earlier this Spring... bloody cool stuff, if you ask me.

The scary bit is that they attribute Venus' drastic climate change to a runaway Greenhouse Effect.

It basically went like this, according to what I was taught:

1) Venus developed much like Earth. Land masses, oceans, the whole bit. Maybe life developed, and happy Venusian lifeforms thrived for a time.

2) This was still early in the Sun's life, and it was cooler back in those days - cool enough that conditions on Venus back then were much like they are now on Earth. But as the Sun matured, it grew hotter. So did Venus. The oceans began to evaporate, progressively faster, forming an ever-increasing cloud layer which only sped the heating of the planet and the evaporation of the oceans. Meanwhile, heavy volcanic activity dumped huge amounts of carbon dioxide into the atmosphere, which made matters worse. At some point, all the water on Venus was scorched away and the planet was baked mercilessly under the pall of its sulfuric atmosphere.

Just a theory, of course, and likely we'll never know. But it's quite intriguing, isn't it?

Time for someone to throw in another twist to the arguement:

Perhaps just perhaps maybe life evolved to a intelligent state and polluted their planet enough for it to be irreversable, just look at what we are doing toourown planet....

Exactly.

And again, we probably could never find out one way or another. It's believed that Venus' surface is reshaped completely every hundred thousand years or so... imagine an entire planet covered kilometers deep in flowing lava. That sorta thing.

But is it enough to convince mankind in general to change? There lies the rub... I don't think it'll happen.

Mankind is convinced, but the ones that lead mankind are not, or they are but are making too much money by dumping toxics, continuing to use fossil fuels, testing nuclear devices..the list is endless but i'm going off topic. but the idea of life once existing on venus is exciting, although as you said there will be no evidence left to support this.

This is my theory on Venus - which in mythology represents love, and a woman. (Mars war and man!)
But like a woman, Venus started out beautiful, a paradise you love to be around and be apart of, wonderful oceans and cool breezes. And just like love is soon changed, it suddenly becomes an impossible environment to survive in, noxious gases and laver spitting volcano’s. But then I have been known to be wrong!