I’ve been observing the constellation Corona Borealis (CrB) as often as possible since late February at around 5 or 6am. Daylight Saving Time ended here just over a week ago. With CrB gradually becoming observable earlier, if I’m still awake at 1am (fairly often), I can observe it (with binoculars) before I go to bed now.
In an October 2024 article in the Research Notes of the American Astronomical Society, When will the Next T CrB Eruption Occur? by Jean Schneider, the author writes:
By going more carefully into the dates of occurrence of the past eruptions, one finds that the successive events date separations are an integer multiple of the orbital revolution period.
…
In summary, the eruptions are not strictly periodic, but the eruptions were all separated by an integer multiple of the orbital period 227.5687 days.
From that, I tentatively infer that the eruption date after 1946 February 9 should be 2431861 + N*227.5687 where N is an integer close to 128, if the orbital period remains constant.
The upshot was predictions for the T CrB eruption of March 27 2025, Nov 10 2025 or June 25 2026. The popular press latched onto this article and suggested a greater certainty than was warranted. It’s now a few weeks after the first of these dates and no nova eruption has occurred yet.
We will see about November. In the meantime, we wait.