Discovered the largest of the famous stars

The largest star ever discovered can give scientists a better understanding of how massive dying stars spread matter around the universe. The W26 star, located in a large cluster of Westerlund 1 in 16,000 light-years from us, is almost 1500 times larger than the Sun, making it the largest star we know. The red supergiant is nearing the end of its life cycle and will eventually turn into a supernova.

Stars with a mass ten times more solar live very short and dramatic lives compared with their less massive "relatives". The life cycle of some of the most massive stars is just a few million years before they exhaust their nuclear fuel and become supernovae. At the very end of life, such stars become very unstable and emit a significant amount of matter from their outer shell.

However, size is not the only remarkable feature of the W26 star. The colossal star is surrounded by a large, luminous cloud of gaseous hydrogen. This is the first detected “ionized nebula” around the red supergiant, which gives scientists new data to study the outer shell dumping stars into interstellar space.
')
W26 is too cold to make the surrounding gas glow. Astronomers suggest that the source of ionizing radiation can be blue stars, also included in the cluster. Or, perhaps, a dimmer, but much hotter star, forming a binary system together with W26. New shots of the supergiant and the Westerlund 1 cluster show that the glowing nebula is green. Despite its decent size, the cluster as a whole looks dim due to interstellar gas and dust.