The good news: Earth can support life for 1.75bn years. The bad news: Climate change could wipe us out first

Scientists calculate planet’s leave-by date, and identify other worlds where life may develop

The end of the world is coming – but not for a while yet. That’s according to a new study indicating that we have 1.75 billion years left until Mother Earth gives up the ghost.

Researchers from the University of East Anglia’s School of Environmental Sciences analysed other planets outside our galaxy in an attempt to work out how long it will be before our planet becomes uninhabitable.

The study, published today in the journal Astrobiology, examined seven planets, including Earth, to determine how their “habitable zones” will change as their stars get hotter and brighter over time.

The key factors in determining a planet’s habitability are whether it is the correct distance from its star to have liquid surface water and a temperature less than 50C.

“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.

The research didn’t specifically account for man-made climate change or the “possibility that we’ll all be wiped out by an asteroid or a nuclear war”, he said. Climate change may well decimate humanity before the concept of habitable zones become relevant.

“Of course, conditions for humans and other complex life will become impossible much sooner – and this is being accelerated by anthropogenic climate change,” he said.

“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.”

Even if some humans did manage to survive for another 1.75 billion years, the end would not come instantly.

“Even if you were alive at 99.9 per cent of the way through our habitable zone, you still wouldn’t have to worry about it,” Mr Rushby said. ”Life isn’t going to be extinguished at the flick of a switch.”

Instead, as the sun gets older, it will get hotter and temperatures on Earth will soar over the course of “perhaps one million years” as we enter a “hot zone” and seas evaporate, leaving the planet lifeless except for some forms of microscopic life.

“The optimist in me hopes we’ll still be around to see this,” said Mr Rushby. “Or that we’ll have migrated to Mars or developed the technology to spread out across the galaxy. But that’s getting into the realms of science fiction.”

The study has also allowed Mr Rushby and his team to make predictions about what stage life might be at in other parts of the galaxy: “There’s no point in studying a planet for signs of life if it’s only been habitable for a million years. That sounds like a long time, but in terms of geology and biology it isn’t. The most interesting planets in the search for alien life are ones that have been habitable for billions of years.

“Anatomically modern humans have only been around for the last 200,000 years – so you can see it takes a really long time for intelligent life to develop.

“Of course, much of evolution is down to luck, so this isn’t concrete, but we know that complex, intelligent species like humans could not emerge after only a few million years because it took us 75 per cent of the entire habitable lifetime of this planet to evolve.

”We think it will probably be a similar story elsewhere.”

In particular, the report points to the examples of Kepler-22b and Gliese-581d which have been habitable  for up to 6 and 54.7 billion years respectively.

“As it stands, we don’t have the technology to explore these planets to discover if there is alien life, but I’d certainly mention Kepler-22b and Gliese-581d as planets that we should keep an eye over the next two or three hundreds years of human existence as our technology develops,” said Mr Rushby.

Start your day with The Independent, sign up for daily news emails
Voices
voices
News
general electionThis quiz matches undecided voters with the best party for them
Life and Style
Men with beards rejoice: Your beard probably doesn't harbour faeces-like bacteria
health
Arts and Entertainment
Keira Knightley and Matthew Macfadyen starred in the big screen adaptation of Austen's novel in 2005
tvStar says studios are forcing actors to get buff for period roles
ebooks
ebooksA celebration of British elections
  • Get to the point
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Ashdown Group: Trainee Consultant - Surrey/ South West London

£22000 per annum + pension,bonus,career progression: Ashdown Group: An establi...

Ashdown Group: Trainee Consultant - Surrey / South West London

£22000 per annum + pension,bonus,career progression: Ashdown Group: An establi...

Ashdown Group: Recruitment Consultant / Account Manager - Surrey / SW London

£40000 per annum + realistic targets: Ashdown Group: A thriving recruitment co...

Ashdown Group: Part-time Payroll Officer - Yorkshire - Professional Services

£25000 per annum: Ashdown Group: A successful professional services firm is lo...

Day In a Page

Fishing for votes with Nigel Farage: The Ukip leader shows how he can work an audience as he casts his line to the disaffected of Grimsby

Fishing is on Nigel Farage's mind

Ukip leader casts a line to the disaffected
Who is bombing whom in the Middle East? It's amazing they don't all hit each other

Who is bombing whom in the Middle East?

Robert Fisk untangles the countries and factions
China's influence on fashion: At the top of the game both creatively and commercially

China's influence on fashion

At the top of the game both creatively and commercially
Lord O’Donnell: Former cabinet secretary on the election and life away from the levers of power

The man known as GOD has a reputation for getting the job done

Lord O'Donnell's three principles of rule
Rainbow shades: It's all bright on the night

Rainbow shades

It's all bright on the night
'It was first time I had ever tasted chocolate. I kept a piece, and when Amsterdam was liberated, I gave it to the first Allied soldier I saw'

Bread from heaven

Dutch survivors thank RAF for World War II drop that saved millions
Britain will be 'run for the wealthy and powerful' if Tories retain power - Labour

How 'the Axe' helped Labour

UK will be 'run for the wealthy and powerful' if Tories retain power
Rare and exclusive video shows the horrific price paid by activists for challenging the rule of jihadist extremists in Syria

The price to be paid for challenging the rule of extremists

A revolution now 'consuming its own children'
Welcome to the world of Megagames

Welcome to the world of Megagames

300 players take part in Watch the Skies! board game in London
'Nymphomaniac' actress reveals what it was really like to star in one of the most explicit films ever

Charlotte Gainsbourg on 'Nymphomaniac'

Starring in one of the most explicit films ever
Robert Fisk in Abu Dhabi: The Emirates' out-of-sight migrant workers helping to build the dream projects of its rulers

Robert Fisk in Abu Dhabi

The Emirates' out-of-sight migrant workers helping to build the dream projects of its rulers
Vince Cable interview: Charging fees for employment tribunals was 'a very bad move'

Vince Cable exclusive interview

Charging fees for employment tribunals was 'a very bad move'
Iwan Rheon interview: Game of Thrones star returns to his Welsh roots to record debut album

Iwan Rheon is returning to his Welsh roots

Rheon is best known for his role as the Bastard of Bolton. It's gruelling playing a sadistic torturer, he tells Craig McLean, but it hasn't stopped him recording an album of Welsh psychedelia
Morne Hardenberg interview: Cameraman for BBC's upcoming show Shark on filming the ocean's most dangerous predator

It's time for my close-up

Meet the man who films great whites for a living
Increasing numbers of homeless people in America keep their mobile phones on the streets

Homeless people keep mobile phones

A homeless person with a smartphone is a common sight in the US. And that's creating a network where the 'hobo' community can share information - and fight stigma - like never before