Evolution pace differentiates climate on Venus, earth

April 6th, 2008 - 5:09 pm ICT by admin  

London, April 6 (IANS) Venus, considered earth’s ‘prodigal twin’, has a climate that is vastly different. And experts say it is because of the pace of evolution on the two planets. According to Fred Taylor of Oxford University, Venus evolved very rapidly compared to the earth in the initial years - a crucial difference.

The new information is being beamed to us from the European Venus Express spacecraft now orbiting Venus.

Data from Venus Express suggests that the earth’s twin once had significant volume of water covering its surface, but these oceans were lost in a very short geological timescale.

As a result, the geological evolution of the surface of Venus slowed down because it was unable to develop plate tectonics like earth. And biological evolution was prevented altogether.

Thus, in terms of Venus being another earth in climate and habitability terms, it evolved too quickly at first, then too slowly.

“They may have started out looking very much the same, but increasingly we have evidence that Venus lost most of its water and Earth lost most of its atmospheric carbon dioxide,” said Taylor, who presented these findings at the National Astronomy Meeting in Belfast Friday.

On earth, CO2 is locked up in minerals in the crust, in the oceans, and in plant life. The release of some of this back into the atmosphere is the source of current concern about global warming and climate change.

On Venus, most of the CO2 is still in the atmosphere and the surface temperature is a scorching 450 degrees Celsius - much too hot for life.

“The interesting thing is that the physics is the same in both cases,” said Taylor.

“The great achievement of Venus Express is that it is putting the climatic behaviour of both planets into a common framework of understanding.”

Tags: , , , , , , , , , , , , , , , , , , ,

Posted in Sci-Tech |