Astronomers have discovered a rare binary star system just 150 light-years from Earth, with two white dwarfs that are destined to produce a Type 1a supernova. This record-breaking binary system is the most massive of its kind ever confirmed, with a combined mass of 1.56 times that of our Sun.
The system’s extraordinary mass guarantees an explosive fate, as it exceeds the critical threshold needed to trigger the supernova process. However, researchers offer reassurance that the explosion won’t occur for approximately 23 billion years, long after our Sun will have exhausted its fuel and died.
As the white dwarfs circle each other in a 14-hour orbit, their emission of gravitational waves will gradually cause them to spiral closer. In the final moments before the supernova, their orbital period will have shortened dramatically to just 30-40 seconds as they approach incredible speeds.
The actual explosion will unfold through a “quadruple detonation” process, with the surface of one white dwarf exploding and triggering secondary detonations that will completely destroy both stars. The energy release is estimated to be a thousand trillion trillion times more powerful than the most powerful nuclear weapon ever created on Earth.
When this event finally unfolds billions of years from now, it will create an astronomically bright point of light in Earth’s night sky, outshining virtually everything else visible to the naked eye and appearing up to ten times brighter than the full moon.
Source: https://www.universetoday.com/articles/theres-a-type-1a-supernova-in-the-making-just-150-light-years-away