In a rare cosmic phenomenon, a star in the ‘Northern Crown’ constellation located 3000 light years away from the Earth, is likely to explode to form a ‘nova’ (a new star). The once-in-a-lifetime phenomenon that occurs once in 80 years last occurred in 1946. If the explosion takes place, the brightness of the star will rapidly increase for a brief time. It will become as bright as the North Star, the 48th brightest star in the night sky, making it visible to the naked for some time.
According to reports, a paper published in Research Notes of the American Astronomical Society predicted three dates for the explosion of the star this year – March 27, November 10 or June 25. Astronomer Franck Marchis at the SETI Institute and co-founder of Unistellar said that the start has been exhibiting variations since last September that suggest that it is about to explode. “However, as the study is still theoretical, its conclusions remain uncertain,” Marchis added.
What is this star and why it explodes?
The star is part of T Corona Borealis (TCrB), a binary star system (a system where two stars are gravitationally bound and orbit each other). The TCrB is classified as a recurrent nova which implies that the star blows its top repeatedly. It is one of the few stars that exhibit such behaviour. The TCrB system has two stars- a red giant and a white dwarf. The Red Giant in the TCrB is cooling and expanding nearing the end of its stellar life. As a result, it consistently releases hydrogen some of which is gathered by the White Dwarf. The explosion occurs in the White Dwarf when the pressure and the temperature on its surface increase and the hydrogen ignites.
Several predictions regarding the explosion of the star have been made over the past two years. The star’s brightness decreases considerably before it explodes. The American Association of Variable Star Observers reportedly observed a decrease in the star’s brightness in March and April 2023 and predicted the explosion in April 2024 but it did not happen. The next timing of its explosion was anticipated to be in September 2024. But it did not explode in September 2024 either. Ever since astronomers and skywatchers have been curiously monitoring and waiting for the explosion. The star last exploded in 1787, 1866 and 1946. The first recorded explosion of the star was in 1217.
