Galaxies grow and as they grow they generate more gravity and pull their neighbors. Our very own Milky Way galaxy will one day become gobbled by the Andromeda Galaxy some five billion years from today. This was revealed in a study which also revealed that gigantic galaxies have stopped making their own stars but are gobbling up their own kind to grow. It is a kind of Galactic cannibalism when a larger galaxy gobbles up a smaller galaxy.
The study involved the analysis of more than 22000 galaxies and it was revealed that smaller galaxies were very apt at creating stars from gas while their larger counterparts grew by consuming the galaxies around them. The study was published in the journal Monthly Notices of the Royal Astronomical Society on Friday.
Aaron Robotham of the International Centre for Radio Astronomy Research, or ICRAR, at the University of Western Australia and the study’s lead author, said in a statement, “All galaxies start off small and grow by collecting gas and quite efficiently turning it into stars. Then every now and then they get completely cannibalized by some much larger galaxy.”
The Milky Way Galaxy also exhibits cannibalism behavior and is expected to increase in size by gobbling up two nearby dwarf galaxies. In about 4 billion years our Milky Way Galaxy will gobble Large and Small Magellanic Clouds. However it will meet its nemesis in the form of Andromeda Galaxy in about 5 Billion years. The Andromeda will eat the Milky Way Galaxy because it is much more gigantic and has a more powerful Gravitational attraction.
The study made use of the data collected from the Anglo-Australian Telescope in New South Wales as part of the Galaxy and Mass Assembly, or GAMA, survey. The GAMA survey involved more than 90 scientists and took more than seven years to complete.
The growing galaxies will generate more and more gravity and will unite galaxies which are scattered in clusters and groups. Ultimately what will be left will be a few super giant galaxies. This process will however take billions of years to happen.