A group of researchers discovered a very distant galaxy, which is about a thousand times brighter than the Milky Way.
As per the researchers, it is the brightest of the submillimetre galaxies, a class of ultraluminous infrared galaxies.
The discovery was published recently in the Astrophysical Journal Letters.
How it is the brightest ever galaxy?
• To measure this galaxy, the researchers used the Gran Telescopio Canarias (GTC) at the Roque de los Muchachos Observatory (Garafía, La Palma) in Spain.
• In order to identify the brightest submillimetre galaxies, researchers carried out a search of the whole sky, combining the data bases of NASA's WISE satellite and European Space Agency's Planck satellite.
• The galaxy's light, amplified by a much nearer galaxy cluster acting as a lens, forms an image which appears much bigger than it should, and it is due to this effect that the researchers could characterise its nature and properties spectroscopically using the GTC.
• This phenomenon, known as gravitational lensing, is comparable to that produced by lenses on light rays, and acts as a sort of magnifier, changing the size and intensity of the apparent image of the original object.
• Due to the gravitational lens produced by a cluster of galaxies between ourselves and the source, which acts as if it was a telescope, the galaxy appears 11 times bigger and brighter than it really is.
• The galaxy is notable for having a high rate of star formation. It is forming stars at a rate of 1000 solar masses per year, compared to the Milky Way, which is forming stars at a rate of some twice a solar mass per year.