R136a1 is believed to be the most massive star in the universe. In 2010, British astronomers in the University of Sheffield discovered the giant star in the Tarantula Nebula through a small satellite galaxy that circles the Milky Way.
While R136a1 is reported to be 265 times more massive than the Sun, it could have been 320 times more once, the discoverers noted. This star is also the most luminous.
It is believed to be 10 million times brighter than our sun and has a temperature of 40,000 degrees Celsius on its surface.
The R136a1 gives off more energy than all stars belonging in the Orion Nebula.