10 ms·
The recurrent nova T CrB had prior eruptions observed in 1787 and 1217 AD (2013)
- ahazred8ta 3y agoT Coronae Borealis is overhead in the evening in July. It's expected to go nova in 2024, brightening from mag10 to mag3. https://en.wikipedia.org/wiki/T_Coronae_Borealis https://en.wikipedia.org/wiki/T_Coronae_Borealis