T Coronae Borealis, the "Blaze Star"
March 13, 2024
Here's the semi-circle of stars comprising the stick figure of
the constellation
Corona Borealis (the Northern Crown) as seen on
March 13, 2024, from
Wharton State Forest, NJ. Mouseover for labels. In
particular, it includes the recurrent nova,
T Coronae Borealis,
which is also known as the
Blaze Star
(not to be confused with the late New Orleans stripper,
Blaze Starr). T CrB is
expected to erupt in the near future from it's
current brightness, nominally magnitude 10.5 visually, to
potentially as bright as magnitude 2.0. There is an extensive
article about this object in the March 2024 issue of Sky &
Telescope magazine, beginning on page 34, and an online
Bob King article posted on June 26, 2024.
The purpose of this snapshot was to have a baseline "before" reference,
while T CrB was in its quiescent state. It was taken at 2:30 am EDT with a Canon EOS RP DSLM
camera plus a Canon 200 mm f/2.8L
telephoto lens on a fixed tripod. It's a single raw frame
exposed 2 seconds at f/2.8, ISO 10,000. It was not adjusted,
just converted to this JPEG with Canon's Digital Photo
Professional 4. The view is 6.9° wide x 10.3° high, but
at that scale, T CrB is barely visible, so
a magnifying crop was was extracted for a better view (see the
image below). The zenith is towards the top, north is
approximately at the 10 o'clock position and east is at 7
o'clock. Alphecca is magnitude 2.2, Epsilon CrB is magnitude 4.2.
T CrB was also seen visually with an 88 mm
spotting scope at 60x. It was faint, but unequivocally there.
Comparing it to nearby field stars, the brightness appeared
consistent with contemporaneous
AAVSO visual magnitude estimates
around
10.5.
Here's the magnifying crop taken from the bottom of the same raw
frame as the image above. Besides cropping to a field 2.5° wide
x 1.6° high, no other adjustments were made (although a red-colored hot
pixel was retouched). Epsilon CrB and T CrB are 63 arc minutes apart (1° 03′).
Here's a AAVSO magnitude reference chart for T CrB.
Decimal points have been omitted from the magnitude values.
