In the second half of 2024, a nova explosion in the star system called T Coronae Borealis, or T CrB, will once again be visible to people on Earth. T CrB will appear 1,500 times brighter than usual, but it won’t be as spectacular as the event in 1054.
Usually stars don’t build up gas. This one is part of a binary system, though, so like the other comment says, it’s siphoning matter from the other one.
the counterintuitive part came for the standard candle supernovae already coming from binary systems and not being recurring, but somehow the recurrent ones manages to blow up with 1/100 of the energy, i am just learning this