The Large Magellanic Cloud, a dwarf galaxy located approximately 163,000 light-years away from Earth, is on a collision course with our Milky Way galaxy with which it will merge in about 2.4 billion years, according to a new published study. in the journal of the Royal Astronomical Society.
This catastrophic event could awaken the latent supermassive black hole of our galaxy (Sagittarius A *), which would begin to devour the surrounding gas and increase its size up to 8 times; the stellar halo of the Milky Way will undergo an equally impressive transformation, becoming 5 times more massive; the merger will also gravitationally eject stars from the central disk in the galactic halo.
Galaxies like our Milky Way are surrounded by a group of smaller satellite galaxies that orbit them, similar to how bees move around a hive.
These satellite galaxies generally live quietly and orbit their hosts for billions of years. However, from time to time, they collide and are eaten by their host galaxy.
The Large Magellanic Cloud is the brightest satellite galaxy in the Milky Way and has been a part of our neighborhood for approximately 1.5 billion years.
Until recently, astronomers thought that it would orbit our galaxy for many billions of years or, because it moves so fast, it would escape the gravitational pull of our galaxy. However, the most recent measurements indicate that the Large Magellanic Cloud has almost twice as much dark matter as previously thought.
“Since it has a greater mass than expected, the Large Magellanic Cloud is rapidly losing energy and is doomed to collide with our galaxy,” said Marius Cautun, an astronomer at Durham University and a co-author of the work.
The researchers used the EAGLE galaxy formation simulation to predict the collision.
“While two billion years is an extremely long time compared to a human lifetime, it is a very short time on cosmic timescales,” Cautun clarifies. ” The destruction of the Large Magellanic Cloud will wreak havoc on our galaxy, awakening the black hole that lives at its center and turning our galaxy into an active galactic nucleus or quasar.”
“This phenomenon will generate powerful jets of high-energy radiation emanating from outside the black hole. While this will not affect our solar system, there is a small chance that we will not be able to escape unscathed from the collision between the two galaxies, potentially pulling us out of the Milky Way into interstellar space, “continues Cautun.
And it is that our universe is in constant evolution and, many times, with violent events such as the collision that is coming with the Large Magellanic Cloud.
“Unless disasters strike, such as a major disturbance to the solar system, our descendants, if any, are going to face a spectacular display of cosmic fireworks and how the newly awakened supermassive black hole at the center of our planet galaxy reacts by emitting jets of extremely bright energetic radiation “, says Carlos Frenk, co-author of the study.
The show will be impressive.
Referencia: Marius Cautun et al, The aftermath of the Great Collision between our Galaxy and the Large Magellanic Cloud, Monthly Notices of the Royal Astronomical Society (2018). DOI: 10.1093/mnras/sty3084
