The Milky Way is slowly ‘separated’ by gravity from a nearby galaxy

The Milky Way galaxy is gradually twisted and distorted by the gravitational force of the Large Magellan’s Cloud (LMC) satellite galaxy, astronomers say.

Researchers at the University of Edinburgh used a statistical model to calculate the speed of stars furthest from the Milky Way and our galactic neighbor.

The discovery upsets the belief that the Milky Way is relatively static, and will therefore require the production of new models to describe the evolution of the galaxy.

The Milky Way is pulled by the gravitational force of the dark matter halo surrounding the LMC at 71,600 miles per hour, distorting it.

This discovery will force researchers to reassess how the Milky Way was formed and what it could mean

Lead author Dr Michael Petersen and his colleagues have shown that CML crossed the Milky Way frontier around 700 million years ago – recently by cosmological standards.

Due to its high dark matter content that surrounds the satellite galaxy, it greatly disrupted the fabric and motion of the Milky Way when it fell.

Dark matter is the mysterious “glue” that holds galaxies together – It has never been directly observed because it does not emit, reflect or absorb light.

The effects of this relatively recent collision are still being seen today – and should force a review of the birth of the Milky Way, Petersen said.

The LMC is now a “ Milky Way satellite galaxy – it is visible as a light cloud in the southern hemisphere night sky.

The Large Magellanic Cloud was named after 16th-century Portuguese explorer Ferdinand Magellan, who was the first to circle the earth.

Previous research has found that the LMC – like the Milky Way and possibly all galaxies – is surrounded by a halo of dark matter beyond the galactic disk.

The researchers revealed that the enormous attraction of the LMC’s dark matter halo is to pull the Milky Way’s disc at 71,600 mph – or 20 miles per second.

To their surprise, the Milky Way was not moving in the direction of the current location of the LMC as previously thought – but at a point in its past trajectory.

It is twisted in the opposite direction – away from the LMC itself – towards the constellation Pegasus – in the northern sky.

This is because the LMC – powered by its massive gravitational force – floats at the even faster speed of 800,000 mph, or 230 miles per second.

The “chase” between the two galaxies has been compared to the Milky Way trying to hit a fast moving target – but not aiming very well.

The discovery will help scientists develop new modeling techniques that capture the strong dynamic interaction between the two galaxies.

Dr Petersen said: ‘We were able to show that stars at incredibly large distances – up to 300,000 light years away – retain a memory of the structure of the Milky Way before the LMC fell and form a backdrop against which we measured the star disk. fly through space, pulled by the gravitational force of the LMC.

Astronomers are now planning to find out the direction from which the LMC first fell – and the exact time it happened.

This will reveal the amount and distribution of dark matter in the Milky Way and CML in unprecedented detail.

Co-author Professor Jorge Penarrubia, also from Edinburgh, said: ‘This discovery definitely breaks the spell that our galaxy is in some kind of steady state.

“In fact, the recent infiltration of LMC is causing violent disturbances in the Milky Way.

“Understanding them can give us unprecedented insight into the distribution of dark matter in the two galaxies.

Last year, a team from Durham University warned that the LMC would destroy Earth in about 2 billion years – by awakening the sleeping black hole in the Milky Way.

The results were published in the journal Nature Astronomy.