Supernova 2025rbs shines as brightest light from distant galaxy

The light from a star that exploded millions of years ago in a distant galaxy, located 500,000 light-years away (one light-year is approximately 9.46 trillion kilometers), has reached Earth. On the 14th, this supernova, initially captured by ground-based telescopes, is called '2025rbs' and is currently observed as the brightest supernova in the night sky. This supernova is estimated to be a Type Ia supernova that exploded after a white dwarf, with a mass similar to that of the Sun, drew material from its companion star and exceeded the critical mass. It serves as a so-called 'standard candle' that helps measure the cosmic distance scale. The galaxy where 2025rbs exploded is the spiral galaxy NGC 7331, located in the direction of the Pegasus constellation, which is also well known for its similarity in structure to our galaxy.