"The Blue Marble" photograph of Earth, taken from Apollo 17
The global population may well heave a sigh of relief. The planet Earth still has a long way to go, 1.75 billion life years at least, making the dreaded Doomsday end-of-the-world scenario still very far off. Unless nations of course simultaneously go dropping nuclear bombs at each other.
A study by researchers from the University of East Anglia's School of Environmental Sciences, published in the journal Astrobiology said that between 1.75 billion and 3.25 billion years from now, the sign the Earth is slowly getting inhabitable is when the ocean waters start to evaporate.
Scientists said the planet will not explode, just that it will get too hot to live.
"Within around 1.75 billion years conditions for human life will become impossible as the sun grows in size, temperatures soar and the world's oceans evaporate," Andrew Rushby, who led the study, told The Independent.
"It will get progressively hotter and there's nothing we can do about it," Mr Rushby, who studies planet habitability at the University of East Anglia, said.
The study was driven to analyse how long it will take before planet Earth becomes uninhabitable. The study examined the "habitable zones" of seven planets, including Earth, to see how it will change as their stars get hotter and brighter over time.
After between 1.75 billion and 3.25 billion from now, "Earth will be in the 'hot zone' of the Sun, with temperatures so high that the seas would evaporate. We would see a catastrophic and terminal extinction event for all life," Mr Rushby said.
However, because of climate change, conditions for humans and other life forms may be shorter than projected.
Planets of the Solar System to scale. Jupiter and Saturn (top row), Uranus and Neptune (top middle), Earth and Venus (bottom middle), Mars and Mercury.
"Humans would be in trouble with even a small increase in temperature, and near the end only microbes in niche environments would be able to endure the heat," he said.
Although the planet Mars is a nice bet for alternative living conditions, "the only problem with Mars is that it doesn't have much atmosphere," Mr Rushby said.
We better start working on our time space warp drives.
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