Warwick, England — In a groundbreaking study, astronomers at the University of Warwick have discovered a binary star system poised to merge and create a spectacular type 1a supernova, an event forecasted to occur 23 billion years from now. This cosmic event, happening within our Milky Way galaxy approximately 150 light years from Earth, will result in an explosion far outshining the Moon.
Type 1a supernovae are categorized as “standard candles,” crucial for astrophysicists to gauge the distance of celestial objects and map the universe effectively. These explosions typically originate from binary white dwarf systems where one star accumulates enough mass from its partner to trigger a thermonuclear explosion.
James Munday, the lead researcher of the study, expressed his excitement about the finding, highlighting the significance due to its rarity and proximity in galactic terms. “Discovering such a system within our galactic neighborhood underscores its likely commonality, suggesting we need not search vast distances to find them,” Munday noted.
His colleague, Dr. Ingrid Pelisoli, emphasized the rarity and importance of the discovery, pointing out its implications for understanding similar systems across the Milky Way. The astronomical team employed some of the world’s largest optical telescopes to study the binary system intensively after initial data suggested its uniqueness.
Utilizing platforms including the Hubble Space Telescope, the researchers established that the two stars are in an extremely close orbit, only 1/60th the distance between the Earth and the Sun. This proximity confirms the duo as a binary system destined to become a supernova — a conclusion underscored by their combined mass, which at 1.56 times that of the Sun virtually guarantees a type 1a supernova event.
As the two stars continue to orbit closer due to gravitational wave radiation, they are expected to experience a dramatic final merger. Theoretical models predict a complex quadruple detonation process where initial explosions on the surface of one white dwarf will set off a chain reaction, culminating in complete obliteration of both stars. This stunning event will be akin to the detonation of a thousand trillion trillion nuclear bombs.
Despite the potentially brilliant spectacle this supernova will one day produce in the sky, it poses no threat to Earth. The 14-hour orbital cycle of the stars is rapidly decreasing, which will ultimately lead to accelerated merging and explosion.
This discovery is not only a milestone for the researchers but also continues to fuel ongoing studies. “Our survey searching for type 1a supernova progenitors is still underway, and we anticipate more significant discoveries,” said Pelisoli. These findings are continually adding pieces to the puzzle of how type 1a supernovae originate, a mystery that astronomers are progressively unraveling.
The findings have been detailed in the paper titled “A Super-Chandrasekhar Mass Type 1a Supernova Progenitor at 49 pc Set to Detonate in 23 Gyr,” published on April 4, 2025, in Nature Astronomy. This discovery not only advances our understanding of stellar life cycles but also enhances our ability to study distant universes by confirming the reliability of standard candles for cosmic measurements.