In the coming months, a once-in-a-lifetime celestial event is set to unfold as the star system T Coronae Borealis (T CrB) is predicted to explode in a spectacular nova outburst. Located 3,000 light-years away from Earth, this binary system consists of a white dwarf and a red giant star, with the white dwarf siphoning off hydrogen-rich matter from its companion. As the stolen material accumulates on the white dwarf’s surface, it eventually reaches a critical temperature, igniting a runaway thermonuclear reaction that results in a dazzling nova explosion.
T CrB is one of only five known recurrent novae in our galaxy, with previous outbursts recorded in 1946, 1866, 1787, and 1217. Astronomers have observed that the system undergoes these explosive events approximately every 80 years, making the upcoming outburst a highly anticipated occurrence. The star system’s erratic behavior over the past decade suggests that the nova is imminent, with experts predicting it will occur between February and September 2024.
Witnessing the Nova with the Unaided Eye
When the nova erupts, T CrB will dramatically increase in brightness, jumping from its normal magnitude of +10 to a stunning magnitude +2. This will make the nova as bright as Polaris, the North Star, and visible to the unaided eye for several days. Bill Cooke, the Meteoroid Environments Office lead at NASA‘s Marshall Space Flight Center, emphasizes the rarity of this event, stating, “It’s a once-in-a-lifetime occurrence. How often can people say that they’ve seen a star explode?“
To catch a glimpse of this celestial wonder, skywatchers should familiarize themselves with the constellation Corona Borealis, or the Northern Crown. This small, semicircular arc is located near the constellations Bootes and Hercules, and it is here that the nova will appear as a “new” bright star. Once the nova reaches its peak brightness, it will remain visible to the naked eye for several days and can be observed with binoculars for just over a week before fading back into obscurity, possibly for another 80 years.
The Science Behind the Spectacle
Novas, often described as “hydrogen bombs” by astrophysicist Bradley Schaefer, result from the explosive pairing between a normal star and a white dwarf. The white dwarf’s intense gravitational pull allows it to steal hydrogen-rich matter from its companion, which accumulates on its surface. As the stolen material piles up, the lower layers become increasingly compressed and heated.
Eventually, the temperature of the compressed matter reaches the kindling point of hydrogen, igniting a runaway nuclear reaction that triggers the apocalyptic blast known as a nova. While this event would be catastrophic for any nearby worlds, stargazers on Earth, safely situated 3,000 light-years away, can marvel at the beauty of this “fun and exciting upcoming cataclysm,” as Dr. Schaefer puts it.