CONTRARY to apocalyptic Mayan warnings, humanity is unlikely to be wiped out in 2012.

But even if we manage to avert a catastrophic asteroid collision scheduled for March 2880, Homo Sapiens will still have to up sticks to a new planet 500 million years from now to avoid mass extinction as an overheating Sun begins boiling the Earth's oceans.

That was the cheerful outlook for humanity presented at the British Science Festival in Aberdeen as researchers considered the when and how of our "Real Doomsday".

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Amid fevered speculation that the Mayan prophecy signals the end of the world in 2012, scientists sought to set the record straight.

Firstly, armageddon is nothing new. Dinosaurs were wiped out 65 million years ago when a giant asteroid collided with Earth and tens of millions of years before that an unknown catastrophic event erased 90% of all species on the planet. Extinction is almost a certainty.

Paleontologist Richard Fortey said: "Fossil records show that the average species on Earth has a lifespan of just two million years before natural selection picks them off. With Homo Sapiens a relatively youthful 100,000-150,000 years old, that gives us 1.85 million years."

But if natural selection doesn't get us, cosmic catastrophe probably will. Current theories include that the imminent reversal of the Sun's magnetic field in 2021, exposure to radiation from increased solar storms or an ominous planetary alignment of five planets plus the Moon in 2040 – creating a gravitational pull that will allegedly draw the Earth away from the Sun – all spell disaster.

But professor Jocelyn Bell Burnell, Oxford University physicist, debunked each in turn.

She said: "The Sun's magnetic field reverses every 11 years. There have been a quarter of a million reversals since our predecessor, Homo Habilis, emerged, and they haven't killed us yet.

"Solar storms cause power outages, they pose a hazard to satellites, they might interfere with your GPS or send your compass a couple of degrees off course. But I don't think solar storms are a life-threatening event.

"And even if every planet in the galaxy ganged up together, they would have zero effect."

But that is not to say that events in space do not pose a genuine danger. Once every 50-100 million years, a meteor measuring more than 1km across hits Earth, thoroughly spoiling the party for everyone.

Bell Burnell said: "An impact of this size if it struck the sea would cause a giant tsunami. If it strikes on land it sends up dust clouds which would circulate the planet and block out the Sun, creating what's known as an 'impact winter'. The lack of sunlight would prevent crop growth, creating a permanent famine which is the eventual cause of extinction."

The next possible impact of this kind is due in March 2880, but scientists are confident that they will have developed methods to safely destroy it by then. Specially designed telescopes around the world are monitoring the movement of 1000 such "near Earth objects" at any one time in an effort to avert such a crisis with technology.

Bell Burnell said: "It's being monitored and we are developing ways of dealing with incoming asteroids and meteors so that they don't cause problems on Earth – maybe using the gravitational pull of giant satellites to divert them from their path. So there's hope on the horizon that we can deal with these things."

Ironically, though, it is the same orb that gives us life on Earth that will one day spell our certain demise – on this planet, at least.

Roughly one billion years from now the Sun will have gobbled up so much hydrogen that it will reach temperatures so scorching that the oceans on Earth will start to boil. Within five billion years, Earth will be an uninhabitable cinder.

"This is going to start to become a problem for us in about 500 million years," said Bell Burnell. "What we would really need is a mass migration to a new planet, a modern-day Noah's Ark. We would have to take all the DNA we needed to start again somewhere else. But those of us who left the old Earth would never see the new Earth, the journey would be so long."

Even uprooting to a new planet is only a stop-gap measure, however.

Extinction of us – and everything else – is guaranteed as every star not only in our solar system but every solar system in the universe will, like our Sun, eventually burn itself out.

"Once a star dies, it's gone forever," said Bell Burnell. "There are no new stars to take its place. Eventually there will be no stars and the universe will turn black. That really will be the end."