Janice R. Andrews
Astronomers warn that any night might provide a “once-in-a-lifetime” vision of a celestial explosion, so keep a watch on the skies. A pair of stars 3,000 light-years away called T Coronae Borealis, or the “Blaze Star,” are predicted to erupt in a stunning show that is observable from Earth.
According to NASA, T Coronae Borealis is a recurrent nova, which means that every 79 to 80 years, it explodes periodically and is visible from Earth. This star system, which is made up of a cold white dwarf star and a hot red giant star, last had an outburst documented in 1946. According to NASA, the next eruption won’t happen until before September 2024.
T Coronae Borealis may be seen between the brilliant stars Vega and Arcturus in the Northern Crown, a horseshoe-shaped starry arc to the west of the Hercules constellation. “It’s going to be one of the brightest stars in the sky” when the explosion is seen, according to Louisiana State University physics and astronomy professor Bradley Schaefer. Schaefer urges everyone to see the explosion as soon as it is apparent by going outdoors.
Schaefer points out that the star system’s past history and the present “pre-eruption dip” suggest the explosion is approaching, even if the precise day and time of the explosion are unknown. An abrupt drop in brightness known as a pre-eruption dip is experienced by some astronomical objects around a year prior to their eruption, as reported by the American Association of Variable Star Observers (AAVSO), who declared in March 2023 that T Coronae Borealis had dimmed.
The magnitude of T Coronae Borealis is typically +10, which NASA states is “far too dim to see with the unaided eye.” On the other hand, the brightness of the star system will increase to magnitude +2 during the explosion, making it readily apparent to the unaided eye.
Schaefer has spent decades researching T Coronae Borealis, and he calls the chance to witness the explosion from Earth “magnificent.” He compares the explosion’s strength to a hydrogen bomb and highlights how humble it is to be present for such a powerful event while remaining unharmed. “It really actually is a hydrogen-fusion bomb just like in the movie ‘Oppenheimer,'” Schaefer clarifies.
NASA says the difference between a nova and a supernova is in what happens following. A supernova destroys the dying star entirely, but a recurrent nova leaves the dwarf star intact during the explosion.
Dr. Rebekah Hounsell is an assistant research scientist at NASA’s Goddard Space Flight Center who specializes in nova events. “There are a few recurrent novas with very short cycles, but typically, we don’t often see a repeated outburst in a human lifetime, and rarely one so relatively close to our own system,” she says. NASA claims that T Coronae Borealis is one of just ten recurrent novas in the Milky Way that erupts on timescales less than a century.
“Having this front-row seat is incredibly exciting,” Hounsell continues. It is anticipated that the star system will shine as brightly as Polaris, the North Star, and that it will do so for several days or maybe a week after it initially appears.
“Generally, nova events are so faint and distant that it’s difficult to precisely pinpoint the location of the erupting energy,” explains Dr. Elizabeth Hays, head of NASA Goddard’s Astroparticle Physics Laboratory. With many eyes watching closely, this one will be closely examined in order to investigate its many wavelengths and, perhaps, provide data that will help us begin to understand the structure and particular processes at play. We eagerly await the complete picture of the situation.”
Even though the precise time and date of the explosion are still unclear, Hounsell thinks that it will motivate next skywatchers. “Young people will have the opportunity to witness a cosmic event, ask their own questions, and gather their own data—it’s a once-in-a-lifetime event that will inspire a lot of new astronomers,” she adds. “It’ll fuel the next generation of scientists.”
Stargazers are encouraged to remain watchful and take in this unique cosmic display, which is a monument to the dynamic and astounding nature of our universe, as excitement grows.
