Researchers at the Leiden Observatory in the Netherlands have recently discovered a galaxy and tagged it as the largest galaxy ever discovered by humans. Apparently, it is 160 times the size of the Milky Way galaxy. Previously the title was held by the galaxy IC 1101, which spanned across 3.9 million light-years. The now discovery is named Alcyoneus, after the son of the primordial Greek god of the sky, Ouranos, and spans across 16.3 million light year making it four times the size of IC 1101.
The discovery of Alcyoneus was possible due to a supermassive blackhole that the galaxy fosters at its centre. The black hole sucks an enormous amount of matter and then spit out gigantic jets of plasma out of it, close to the speed of light. These plasmas subdue after travelling million of light years before converting into plumes of radio waves. These plumes detected from the radio galaxy are by far the largest ever discovered, this lead the scientist to find the now largest galaxy in the Universe.
Scientists were flabbergasted by the discovery and came up with bunch of questions regarding it. However, to answer the questions they came up with theories, one of which is that the galaxy being surrounded by a low-density environment resulted in it’s plasma jets to expand unprecendentedly.
Martjin Oei, the lead astronomer of the project wrote in their preprint paper that if the characteristics of the existing host galaxy are an important cause for giant radio galaxy growth, then the hosts of the largest giant radio galaxies are likely to possess them. The paper will be published in Astronomy and Astrophysics.
The Alcyoneus galaxy was discovered using the Europe -based LOw-frequency ARray(LOFAR) and the data from NASA’s Wide-field Infrared Survey Explorer satellite observatory. It is roughly 3 billion light years away from Earth and almost 240 billion times the size of our sun.
By comparing the data with the formation of the largest galaxy ever discovered, scientists are expecting to gain more insights into the formation of galaxies.