The heaviest known star – with a mass 320 times greater than the Sun's – has been discovered at the edge of our galaxy by British astronomers. Scientists at the University of Sheffield found the stellar giant – named R136a1 – using the European southern Observatory's Very Large Telescope in Chile and data from the Hubble Space Telescope.
The star is located in the Tarantula Nebula in the Large Magellanic Cloud, a small "satellite" galaxy which orbits the Milky Way. Previously, the heaviest known stars were around 150 times the mass of the Sun, and this was believed to be close to the cosmic size limit.
As stars get more massive the amount of energy created in their cores grows at a faster rate than the force of gravity which holds them together. The torrents of energy produced eventually become so powerful that the stars are torn apart.
This is known as the "Eddington Limit", after the British physicist Arthur Eddington who, in 1919, proved Einstein's theory of relativity by showing that light is bent by gravity.