Once in a Lifetime: T Coronae Borealis to Undergo Rare Thermonuclear Detonation in 2021

The star T Coronae Borealis (T CrB) is set to undergo a thermonuclear detonation on its surface, an event that happens roughly once every 80 years. This explosion is predicted to make the star visible to the human eye without any aids, a sight not witnessed since the 1940s.

The chart provided shows the view from London looking south-south-west around 2300 BST, indicating where to monitor for any changes. When T CrB erupts, it is expected to shine as brightly as Alphecca, the brightest star in the Corona Borealis constellation, also known as the northern crown.

The Astronomical League advises people to sketch the constellation regularly when the star eventually erupts. This practice will aid in determining the precise time when the eruption’s light reaches Earth. Although the explosion has already occurred, T CrB is located an enormous 2,600 light years away, meaning that its light has been traveling through space for centuries. Now, it’s just a matter of weeks or even days before we witness it here on Earth.

For those observing from Sydney, Australia, the constellation will reach its highest point due north around 2100 AEST. This positioning will provide an optimal view of the celestial event and allow for a unique perspective on this rare occurrence.