T CrB is a recurrent nova that is currently of interest because it is likely to go nova sometime soon. The last two eruptions were in 1866 and 1946 (a separation of 80 years) and the current prediction for the next one is 2024.4+/-0.3. It could reach magnitude 2 which would mean it would be roughly as bright as alpha CrB.
The BAA have 3 useful charts to use when locating T. These are a wide 50 degree field, a 9 degree field for use with binoculars and an inverted 2 degree field to be used with a telescope. The chart number is 025.04. T is located near Epsilon CrB. This star (labelled A on the 9 degree chart) forms a roughly equilateral triangle with the stars labelled E and F. T is to the west side of the line between A and F and a roughly halfway between them. There is a small group of three stars to the east of this line which point towards it.
At the moment (5th January 2024) T is about 10th magnitude. Members of the BAA variable star section have obviously been asked to keep an eye on this star but currently the constellation of Corona Borealis is only visible in the morning before sunrise.
On Boxing Day morning just passed (the 26th December) I happened to be awake around 6am and so I thought I would check to see if the nova had appeared. The sky was clear but the moon (1 day before full) was still in the sky in the west and astronomical twilight began at 06:00 UT. Nothing was obvious to the naked eye around that time. With 7x50 binoculars I searched for the location of T without seeing anything. The faintest star I could see in the area (at 06:32 UT) was the star labelled P which was magnitude 8.4. So T was fainter than this at this time. The last confirmed visual observation of this star was around the 1st December but there have been some CCD determinations. So I must try and get up early one morning soon and have a go with the telescope.
All text and images © Duncan Hale-Sutton 2024
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