Milky Way Heading for Catastrophic Collision

The Whirlpool Galaxy (M51a) and companion galaxy (M51b). This Hubble Space Telescope image represents a merger between two galaxies similar in mass to the Milky Way and the Large Magellanic Cloud. (Image: NASA, ESA, S. Beckwith (STScI), and The Hubble Heritage Team (STScI/AURA))
The Whirlpool Galaxy (M51a) and companion galaxy (M51b). This Hubble Space Telescope image represents a merger between two galaxies similar in mass to the Milky Way and the Large Magellanic Cloud. (Image: NASA, ESA, S. Beckwith (STScI), and The Hubble Heritage Team (STScI/AURA))

New research led by astrophysicists at Durham University, UK, predicts that the Large Magellanic Cloud (LMC) could hit the Milky Way in 2 billion years’ time.

The collision could occur much earlier than the predicted impact between the Milky Way and another neighboring galaxy, Andromeda, which scientists say will hit our galaxy in 8 billion years. The catastrophic coming together with the Large Magellanic Cloud could wake up our galaxy’s dormant black hole, which would begin devouring surrounding gas and increase in size by up to 10 times.

As it feeds, the now-active black hole would throw out high-energy radiation and while these cosmic fireworks are unlikely to affect life on Earth, the scientists say there is a small chance that the initial collision could send our Solar System hurtling into space. The findings were published in the journal Monthly Notices of the Royal Astronomical Society.

Galaxies like our own Milky Way are surrounded by a group of smaller satellite galaxies that orbit around them, in a similar way to how bees move around a hive. Typically, these satellite galaxies have a quiet life and orbit around their hosts for many billions of years. However, from time to time, they sink to the centre, collide, and are devoured by their host galaxy.

Above is a simulation of the evolution of a galaxy similar to our own. The bright regions correspond to stars. The video shows the approach of a secondary smaller galaxy, a so-called satellite galaxy, that shortly afterward gets devoured by the central galaxy. As the smaller galaxy gets destroyed, stars get ejected from the central region. Although the chances are small, our Sun could be one of those stars condemned to a long and lonely wander through the cold and dark intergalactic space. The movie shows a similar evolution to what researchers predict for the collision between our galaxy and the Large Magellanic Cloud. (Image: The Auriga project / carried out by researchers at the Institute for Computational Cosmology, Durham University, UK, the Heidelberg Institute for Theoretical Studies, Germany, and the Max Planck Institute for Astrophysics, Germany)

The Large Magellanic Cloud is the brightest satellite galaxy of the Milky Way and only entered our neighborhood about 1.5 billion years ago. It sits about 163,000 light years from the Milky Way. Until recently, astronomers thought that it would either orbit the Milky Way for many billions of years or, since it moves so fast, escape from our galaxy’s gravitational pull.

However, recent measurements indicate that the Large Magellanic Cloud has nearly twice as much dark matter than previously thought. The researchers say that since it has a larger than expected mass, the Large Magellanic Cloud is rapidly losing energy and is doomed to collide with our galaxy.

This vibrant image from NASA's Spitzer Space Telescope shows the Large Magellanic Cloud, a satellite galaxy to our own Milky Way galaxy. (Credit: NASA/JPL-Caltech/STScI)

This vibrant image from NASA’s Spitzer Space Telescope shows the Large Magellanic Cloud, a satellite galaxy to our own Milky Way galaxy. (Image: NASA / JPL-Caltech / STScI)

The research team, led by scientists at Durham University’s Institute for Computational Cosmology working with the University of Helsinki, in Finland, used the EAGLE galaxy formation supercomputer simulation to predict the collision. Lead author Dr. Marius Cautun, a postdoctoral fellow in Durham University’s Institute for Computational Cosmology, said:

The collision between the Large Magellanic Cloud and the Milky Way could be spectacular, the researchers say. Co-author Professor Carlos Frenk, Director of the Institute for Computational Cosmology, Durham University, said:

According to the researchers, the merger of the two galaxies could be long overdue in cosmic terms. Dr. Alis Deason, of Durham University’s Institute for Computational Cosmology, said:

Provided by: Durham University [Note: Materials may be edited for content and length.]

Like this article? Subscribe to our weekly email for more!     

Unusual Supernova Opens a Rare Window on the Collapse of a Star
Will the Chinese Ever Line Up to Purchase Apple iPhones Again?