A ‘monster cannibal galaxy’ is going to eat the Milky Way, scientists confirm

The galaxy next to our own is a ‘cannibal’ that has ‘set its eyes’ on the Milky Way, scientists have warned.

It’s long been known that Andromeda will smash into humanity’s home galaxy in the future.

Now astronomers have uncovered new details of this galactic ‘monster’s’ murderous past.

A team from the Australian National University has discovered large ‘streams of stars’ which indicate Andromeda munched several smaller galaxies within the past few billion years.

It may even have ‘gobbled up’ galaxies 10 billion years ago when it was first forming.

‘The Milky Way is on a collision course with Andromeda in about four billion years.,’ said Dr Dr Dougal Mackey, from the ANU Research School of Astronomy and Astrophysics.

So knowing what kind of a monster our galaxy is up against is useful in finding out the Milky Way’s ultimate fate.’

‘Andromeda has a much bigger and more complex stellar halo than the Milky Way, which indicates that it has cannibalised many more galaxies, possibly larger ones.’

The scientists analysed clumps of stars called globular clusters to reveal ‘signs of ancient feasting’.

‘By tracing the faint remains of these smaller galaxies with embedded star clusters, we’ve been able to recreate the way Andromeda drew them in and ultimately enveloped them at the different times,’ Dr Mackey added.

The scientist believes Andromeda also fed in two different directions, pulling in material from two sides.

‘This is very weird and suggests that the extragalactic meals are fed from what’s known as the ‘cosmic web’ of matter that threads the universe,’ said Professor Geraint Lewis from the Sydney Institute for Astronomy and University of Sydney School of Physics.

‘More surprising is the discovery that the direction of the ancient feeding is the same as the bizarre “plane of satellites”, an unexpected alignment of dwarf galaxies orbiting Andromeda.

‘This deepens the mystery as the plane must be young, but it appears to be aligned with ancient feeding of dwarf galaxies. Maybe this is because of the cosmic web, but really, this is only speculation.

‘We’re going to have to think quite hard to unravel what this is telling us.’

‘We are cosmic archaeologists, except we are digging through the fossils of long-dead galaxies rather than human history.’

Scientists recently worked out how long we’ve got until the Milky Way smashes into a neighbouring galaxy – and you don’t need to be too worried just yet.

It’s now believed this will happen in 4.5 billion years time, rather than 3.9 billion years into the future.

Astronomers used data from the European Space Agency’s Gaia satellite to study the movements of Andromeda.

They said the collision will happen later than expected and will also be ‘less destructive’, with the two galaxies hitting each other in a ‘glancing blow’ rather than a head-on collision.

‘This finding is crucial to our understanding of how galaxies evolve and interact,’ said Timo Prusti, ESA Gaia Project Scientist.