Venus may have hosted liquid water for 2-3 billion years, until a dramatic transformation starting over 700 million years ago resurfaced around 80 per cent of the planet, according to a Nasa study.
The research gives a new view of Venus’s climatic history. Forty years ago, Nasa’s Pioneer Venus mission found tantalising hints that Earth’s “twisted sister” planet may once have had a shallow ocean’s worth of water.
To see if Venus might ever have had a stable climate capable of supporting liquid water, researchers from Nasa Goddard Institute for Space Studies created a series of five simulations assuming different levels of water coverage.
In all five scenarios, they found that Venus was able to maintain stable temperatures between a maximum of about 50 degrees Celsius and a minimum of about 20 degrees.