A star 10 million times brighter than Sun discovered

Found within two young star clusters, NGC 3603 and RMC 136a, the stars weigh up to 300 times the mass of the Sun -- a figure which doubles the previously accepted limit of solar mass.

A team of scientists who discovered the star using the European southern Observatory's (ESO) Very Large Telescope at the University of Sheffield identified it among a group of "monster" stars -- whose size and brightness exceed what many scientists thought was possible.

The star, known as R136a1, has a current mass of 265 solar masses, and it is thought its birthweight was as much as 320 times that of the Sun, the Telegraph reported.

The biggest star is located in within the R136a cluster of a neighbouring galaxy more than 165,000 light years away from Earth -- an area where stars are being born from extensive clouds of gas and dust.

According to the scientists, it is also the most luminous star ever found, close to 10 million times that of the Sun.

If R136a1 replaced the Sun at the centre of our solar system, it would outshine our star by as much as the Sun currently outshines the Moon, they said.

Lead researcher Paul Crowther, a professor of Astrophysics from the University of Sheffield, said: "Unlike humans, these stars are born heavy and lose weight as they age.
"Being a little over a million-years-old, the most extreme star R136a1 is already 'middle-aged' and has undergone an intense weight loss programme, shedding a fifth of its initial mass over that time, or more than fifty solar masses.

"Owing to the rarity of these monsters, I think it is unlikely that this new record will be broken any time soon."

Due to the short lives of these very rare, high mass stars, it remained a challenge for astronomers to identify how they originated, he said.
"Either they were born so big or smaller stars merged together to produce them," he speculated.

Raphael Hirschi, from Keele University, added: "Its high mass would reduce the length of the Earth's year to three weeks, and it would bathe the Earth in incredibly intense ultraviolet radiation, rendering life on our planet impossible."