Crunch time for our planet
A neighbouring galaxy is hurtling towards the Milky Way on a collision course that could shift Earth outside the so-called Goldilocks zone, making it too hot or too cold for life.
Astrophysicists at Durham University predict that the Large Magellanic Cloud (LMC) could hit the Milky Way in two billion years’ time.
Although the collision would not directly affect the solar system, it would trigger events that could alter the orbit of planets and end life on Earth two billion years sooner than expected.
Dr Marius Cautun, lead author of the research and a postdoctoral fellow at the university’s Institute for Computational Cosmology, said: “Even small variations in the distance between the Earth and the Sun can move our planet outside the Goldilocks zone and make it either too hot or too cold for life.”
The LMC, the brightest satellite galaxy of the Milky Way, is about 163,000 light years away. Measurements indicate it has nearly twice as much dark matter as previously thought, meaning it is doomed to collide with our galaxy.
A catastrophic crash could wake up a dormant black hole in the Milky Way, which would begin devouring surrounding gas, expand in size by up to 10 times and, potentially, fling the Solar System into intergalactic space.
Until now, scientists have predicted life on Earth would be wiped out about four billion years from now by changes in the Sun.
The findings are published in the journal Monthly Notices of the Royal Astronomical Society.