T CrB #NOVA #WATCH
today: m=10.1 (July 13.1)
yesterday: m=10.2
more: AAVSO data | sky map

Explanation: When the nova explodes, the visual magnitude of the #star (m) will jump from +10 (invisible to the naked eye) to +2 (about as bright as the North Star).

https://spaceweather.com/