'150 light-years away': A supernova explosion will light up Earth brighter than Moon, but you won't like the timing of it
Produced by Tarun Mishra
Produced by Tarun Mishra
Astronomers have identified a binary white dwarf system, located just 150 light-years from Earth, that is expected to end in a rare quadruple supernova. The system, named WDJ181058.67+311940.94, is the first of its kind confirmed to lead to a type 1a supernova.
The event is predicted to occur approximately 22.6 billion years in the future, well beyond the expected lifespan of Earth or its moon, both of which would likely be destroyed by the Sun’s expansion before then.
If the explosion were visible today, it would shine with an apparent magnitude of minus 16 — around 200,000 times brighter than Jupiter appears in the night sky and ten times brighter than the full moon.
Simulations suggest the supernova will involve four separate explosions. The sequence begins with an outer surface detonation on one white dwarf, followed by a core explosion. The debris from these will then trigger similar blasts in the companion star.
The white dwarfs have a combined mass of 1.56 times that of the Sun — unusually high for such systems — and orbit one another every 14 hours. Over time, gravitational forces will reduce their orbital period to under a minute, leading to mass transfer and eventual detonation.
These explosions, known as “standard candles,” are important to cosmologists for measuring distances across space and calculating the universe’s expansion rate. This discovery strengthens the theory that many such supernovae originate from similar binary systems.
Researchers say that finding such a system so close to Earth implies that similar systems may be more common than previously believed. Ongoing surveys are expected to identify additional type 1a candidates in the coming years.