Scientists have announced that a dim star in a constellation easily visible after dark from the Northern Hemisphere may be on the verge of exploding.
The binary star system, called T Corona Borealis, dramatically brightens approximately every 80 years and was last observed doing so in 1946, making it a once-in-a-lifetime event. It could become visible to the naked eye this week.
According to empirical extrapolations, the long-anticipated “nova” (new star) is thought to be heading for an eruption on Thursday 27 March 2025, after which it’s predicted to become visible to the naked eye for a few nights. T Coronae Borealis, also known as the Blaze Star, is actually a pair of stars located 3,000 light-years away. The star system is a recurring nova, with Earth-visible explosions every 79 to 80 years, according to NASA.
It consists of a white dwarf star (a star that’s exhausted its fuel and is cooling down) and a red giant star (a star that's cooling and expanding as it ages, expelling material as it does.
Over time, the white dwarf accumulates material spilling from the red giant star until it finally triggers a thermonuclear explosion. This explosion causes a sudden and dramatic increase in brightness, allowing the star, usually too dim to see, to become visible to the naked eye from Earth.
There are records of the Blaze Star exploding in 1787 and 1866 as well as in 1946, making it a predictable event seen by different generations of astronomers. The exact day and time of the explosion cannot be predicted but looking at the star system's historical behaviour and its pre-eruption brightness dip indicate the explosion is imminent.
The constellation Corona Borealis - a curve of seven stars - rises in the east about three hours after sunset, as seen from the Northern Hemisphere, and will be easy to see an hour after that.