The Largest Star In The Known Universe

Stephenson 2-18 is so gargantuan that if it replaced our Sun, its outer edge would swallow the orbit of Saturn. It is currently considered one of the largest stars ever discovered by astronomers.

This massive red hypergiant is so wide that it would take a beam of light nearly nine hours just to travel around its circumference. For comparison, it would take light only a few seconds to circle our Sun. While it is located nearly 20,000 light-years away, its sheer scale defies typical stellar models. Scientists continue to debate its exact size, but it remains a true titan among the stars.