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Scientists have revealed a grim prospect for humanity's future, as they warn Earth will eventually be consumed by the sun.
In roughly five billion years, our star will burn the last of its hydrogen fuel and begin expanding into a monstrous red giant.
When this happens, astronomers from the University College London and the University of Warwick predict that Earth will be swallowed by the sun or torn to pieces.
Even if Earth survives our star's transformation, the researchers warn that life on our planet will not.
Our demise will likely be caused by powerful gravitational effects known as 'tidal forces', according to the team.
Lead author, Dr Edward Bryant says: 'Just like the Moon pulls on Earth's oceans to create tides, the planet pulls on the star.
'As the star evolves and expands, this interaction becomes stronger.
'These interactions slow the planet down and cause its orbit to shrink, making it spiral inwards until it either breaks apart or falls into the star.'
Scientists have given a terrifying glimpse into the future as they warn that Earth will eventually be swallowed by the sun (artist's impression)
This terrifying discovery was made by looking at nearly half a million stars that had just entered this 'post–main sequence' stage of their lives.
Main–sequence stars, like our sun, are stable because the inward force of gravity is balanced by the outward push from nuclear fusion reactions in their core.
But when stars run out of hydrogen to burn, this balance is disturbed, and the star begins to collapse in on itself.
This collapse makes the core hot enough to fuse helium atoms into carbon, releasing a surge of energy that kickstarts nuclear fusion in the outer layers, which then expand and cool.
During this process, a red giant can become anywhere from 100 to 1,000 times larger.
Using a computer programme, the researchers searched for the tiny dips in brightness caused by an orbiting planet passing in front of post–main sequence
Out of 15,000 possible signals, Dr Bryant and his co–author were able to identify 130 giant planets orbiting close to their stars, 33 of which were previously undiscovered.
They found that stars that had already expanded and cooled into red giants were much less likely to host large, close–orbiting planets.
In about five billion years, scientists say that the sun will burn the last of its hydrogen fuel. When this happens, it will expand to about 200 times its current size to become a red giant and destroy Earth (artist's impression)
A star's life cycle
Around 90 per cent of stars in the sun are what scientists call 'main sequence' stars.
These are stars that fuse hydrogen into helium in their cores, and range from about a tenth of the mass of the sun to about 200 times as massive.
Main sequence stars start as clouds of gas and dust, which collapse under gravity into 'protostars'.
When a protostar is dense enough, the pressure and heat start nuclear fusion and a star is born.
Stars keep burning helium until it runs out in around 10 to 20 billion years.
At this point, stars will enter the post–main sequence phase and become red dwarfs, white dwarfs, red giants, or even explode into neutron stars, depending on their size.
Overall, 0.28 per cent of stars surveyed were home to a giant planet, with the youngest stars in the sequence having planets more frequently.
However, for planets that had already grown enough to be classed as red giants, just 0.11 per cent were home to planets.
'This is strong evidence that as stars evolve off their main sequence they can quickly cause planets to spiral into them and be destroyed,' says Dr Bryant.
'We expected to see this effect, but we were still surprised by just how efficient these stars seem to be at engulfing their close planets.'
Worryingly, the researchers believe that the same thing will eventually happen to Earth.
Scientists currently predict that the Sun will become a red giant in about five billion years, and this study suggests the prospects for Earth are not good.
Co–author Dr Vincent Van Eylen, of University College London, says: 'When this happens, will the solar system planets survive? We are finding that in some cases planets do not.'
Earth is likely to be safer than the giant planets in the study, which orbit very close to their stars.
The researchers studied thousands of stars that had transitioned into red giants and found that these were less likely to host large planets, suggesting that the stars had destroyed them already (artist's impression)
However, the researchers only looked at the first one to two million years of the 'post–main sequence' phase.
That means these stars have a long way still to evolve and could be even more destructive in the years to come.
Research suggests that the sun will grow so much that it swallows the two inner planets, Mercury and Venus, but might not reach the Earth.
In either case, scientists predict that humanity is not likely to survive the sun's evolution.
Dr Bryant told Daily Mail: 'Life on the surface would not survive.
'The expansion of the Sun would drastically increase the level of radiation received at the surface of the Earth, dramatically increase the surface temperature and render the planet uninhabitable.'
Scientists predict that the intense heat from the expanding sun will strip Earth of its atmosphere and boil away the oceans.
So, even if Earth is not torn apart by gravity, there probably won't be any humans left to celebrate.
WHAT WILL HAPPEN TO EARTH WHEN THE SUN DIES?
Five billion years from now, it's said the Sun will have grown into a red giant star, more than a hundred times larger than its current size.
Eventually, it will eject gas and dust to create an 'envelope' accounting for as much as half its mass.
The core will become a tiny white dwarf star. This will shine for thousands of years, illuminating the envelope to create a ring-shaped planetary nebula.
Five billion years from now, it's said the Sun will have grown into a red giant star, more than a hundred times larger than its current size
While this metamorphosis will change the solar system, scientists are unsure what will happen to the third rock from the Sun.
We already know that our Sun will be bigger and brighter, so that it will probably destroy any form of life on our planet.
But whether the Earth's rocky core will survive is uncertain.
