<p><br /> Astronomers have discovered "monster" stars - whose size and brightness exceed what many scientists thought was possible.<br /> </p><p><br /> 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.<br /> </p><p><br /> A researcher at the University of Sheffield discovered the monster stars using the European Southern Observatory's (ESO) Very Large Telescope.<br /> </p><p><br /> The biggest star found, R136a1 within the R136a cluster, has a current mass of 265 solar masses, and it is thought its birthweight was as much as 320 times that of the Sun.<br /> </p><p><br /> It is also the most luminous star ever found, close to ten million times that of the Sun.<br /> </p><p><br /> 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.<br /> </p><p><br /> Due to the short lives of these very rare, high mass stars, it remained a challenge for astronomers to identify how they originated.<br /> </p>
