The cloud-shrouded planet most likely started with oceans much like Earth's, which evaporated as Venus heated up, according to new research.
The oceans didn't disappear overnight, said David Grinspoon of the Denver Museum of Nature and Science.
Speaking yesterday at a meeting of planetary scientists in Orlando, Florida, Grinspoon said that preliminary results of new computer models indicate Venus may have retained its oceans for a billion years after it formed, possibly longer.
Prior models had indicated that rising Venusian temperatures had turned the oceans to steam within the planet's first 600 million years.
The extra 400 million years are even more significant than they sound, Grinspoon added, because early Venus was constantly bombarded by asteroids, reducing the likelihood of life.
The new finding suggests that the oceans existed for much longer after the asteroid bombardment tapered off.
The article goes on to say that there might have been a significant period of time where Venus was inhabitable. That would be stretching it I think. It's unlikely that Venus had complex, multicelluar organisms. The big bang of that didn't happen on Earth for some time after the oxygen crisis. Indeed, it took life billions of years to even hit the point where there was an oxygen crisis where O2 was prevalent enough that it poisoned some of the older kinds of life and allowed the innovations that led up to the multicelluar lifeforms that we find in our fossil record. It's highly doubtful that the Venusian life even made it to the complexity of the Ediacarian/Vendian lifeforms.
No matter what, even if there was some oxygen in the atmosphere, no human could have lived there in shirt sleeves.
Yeah, but Venus might have been oxygenated early, as the rapid escape of hydrogen left oxygen behind. In this sense, it could have been a much better place for the evolution of "advanced" life forms.
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