by From Will Dunham
Washington (Reuters) -The Milky Way and the neighboring Andromeda galaxy are currently race at a speed of around 250,000 miles per hour (400,000 km / h) and set up a possible future galactic collision, both of which destroy them.
But how likely is this cosmic crash? While earlier research was forecast in about 4 to 4.5 billion years, a new study in which recent observation data is used and add new variables that a collision is far from secure. It is the likelihood of a collision in the next 5 billion years with less than 2% and one in the next 10 billion years at around 50%.
Galactic mergers are not like a demolition, with stars and planets that plunge each other, but a complicated mixture on an immense scale.
“The future collision – if it happens – would be the end of both the Milky Way and Andromeda,” said the astrophysicist of the University of Helsinki, Till Sawala, leading author of the study, which was published on Monday in the Nature Astronomy magazine.
“If a merger takes place, it is more likely that it will appear 7-8 billion years in the future. But we find that due to the current data we cannot predict the time of a merger if this happens at all,” said Sawala.
The two galaxies are currently around 2.5 billion light years apart. A light year is the distance light in one year, 9.5 trillion km (5.9 trillion miles).
In the future, the potential collision is so far that the earth becomes a completely different kind of place at that time. It is expected that our planet will become uninhabitable in about a billion years, with the sun so hot that it boils the oceans of our planet. The sun is one of the many billions of stars in the Milky Way. The total mass of our spiral galaxy – including its stars and interstellar gas as well as its dark matter, which is invisible material, the presence of which shows through its gravitational effects – is estimated at about a trillion – sometimes the mass of the sun.
Andromeda galaxy has a shape and a total mass that resembles the milky way.
The researchers simulated the movement of the Milky Way in the next 10 billion years with updated data from the Gaia and Hubble world space telescopes and various floor-based telescopes as well as revised galactic mass estimates.
Other galaxies nearby are forecast to determine whether a collision occurs. Earlier investigations made up the gravitational influence of the Triangulum galaxy, also Messier 33 or M33, which is about half the size of the Milky Way and Andromeda, viewed the large Magellan cloud, a smaller satellite galaxy of the Milky Way.
“We find that if only M33 is added to the two-body system, the likelihood of a milky way andromeda fusion actually takes, but the inclusion of the great Magellan cloud has the opposite effect,” said Sawala.
The researchers came to the conclusion that a merger between the Milky Way and the Great Magellan Cloud is almost certain in the next 2 billion years, long before a potential collision with Andromeda.
A remarkable difference between the Milky Way and Andromeda is the mass of the super massive black holes in their centers. The shooter A*or SGR A*is about 4 million times the mass of the sun. The Andromeda counterpart is around 100 million of the sun.
“Collisions between stars are very unlikely, but the two super -massive black holes would sink into the middle of the newly shaped galaxy, where they finally merge,” said Sawala.
Galactic mergers have occurred since the early stages of the universe and are particularly common in areas of the universe in which galaxies are met.
“In the early universe, galaxy fusions were much more common, so the first mergers had occurred very shortly after the first galaxies were founded,” said Sawala.
“Smaller mergers – with a lot of smaller galaxies – appear more often. In fact, the Milky Way is currently fitting several dwarf galaxies,” said Sawala.
(Reporting according to Will Dunham; Editor from Sandra Maler)
