Outrageously-luminous galaxies discovered that were not predicted to existStaff writer ▼ | March 24, 2016
Astronomers have found the brightest galaxies ever observed. These galaxies are 300 trillion times brighter than the Sun, and scientists say they did not know they could physically exist.
Discovery 300 trillion times brighter than Sun
Astronomers from the University of Massachusetts Amherst found eight galaxies, all around 10 billion years old. They say they are far brighter than any other galaxy seen to date.
Min Yun, researcher working on the study said: "The galaxies we found were not predicted by theory to exist; they're too big and too bright, so no one really looked for them before."
Astronomers categorise a galaxy's luminosity by comparing it to the Sun. A galaxy that is 'ultra-luminous' has a luminosity of 1 trillion Suns. At 10 trillion Suns, it is described as "hyper-luminous".
The researchers say that these galaxies are 300 trillion times more luminous than the Sun. As it stands, there is no term given to a galaxy brighter than 100 trillion times the Sun.
Lead author Kevin Harrington said: "We've taken to calling them 'outrageously-luminous' among ourselves, because there is no scientific term to apply."
The researchers analysed these galaxies and discovered the most likely cause of their brightness was a high rate of star formation. They say that the galaxies appear to be forming a new star every hour.
"We still don't know how many tens to hundreds of solar masses of gas can be converted into stars so efficiently in these objects, and studying these objects might help us to find out," said Harrington. ■