Message from the President
T Coronae Borealis, commonly known as the Blaze Star, is a recurrent nova that has captured the attention of astronomers for centuries due to its periodic outbursts. The star system, located around 2,000 light-years away in the constellation Corona Borealis, consists of a red giant and a white dwarf in a close binary orbit. As material from the red giant falls onto the white dwarf, it accumulates until it triggers a thermonuclear runaway, resulting in a bright nova outburst. T CrB is of particular interest because it has only erupted twice in modern times—once in 1866 and again in 1946. With 2024 marking nearly 80 years since the last event, astronomers are anticipating another potential outburst soon.
This upcoming possible eruption presents an exciting opportunity for astronomy enthusiasts, especially those with access to telescopes and cameras. During past eruptions, the star’s brightness increased dramatically, reaching up to magnitude 2.5, making it visible to the naked eye. Right now as we await this dramatic event, we have to use a telescope to see the star as it is currently only shining at an apparent magnitude of about 10. This means you will need a 4-inch to 6-inch telescope to see it. However, if you have access to a telescope with an astronomy camera you can use a much smaller telescope. Here is a crop of a recent picture I took of this star using the club’s smaller 60mm (or 3 inch) Gateway Remote Telescope. With an astronomy camera you can push the magnitude limit way down, not only can we easily capture T CrB at magnitude 10, but we can even pick up the small elliptical galaxy, IC 4587 which is 650 million light years distant and shines at just 15.8 magnitude. Without a camera our eyes would require a telescope with at least a 12-inch diameter mirror to spot that galaxy!
If we pull back to the entire field of view from the small telescope, we can see a much larger frame where the bright star to the lower left is the bright star Epsilon CrB which shines at magnitude 4 and should be visible to the naked eye in a darker location outside of New York City.
And here we have an image of a star chart from Sky and Telescope magazine, showing the approximate location of the above field of view circled in red.
Credit: Sky & Telescope Magazine
We can see the very bright star Alphecca off to the right. Now what makes this really neat is when T CrB goes nova it may shine at similar brightness as Alphecca which is a magnitude 2 star and easily visible even from the light pollution of New York City. So the next time you are out strolling around, if you happen to look up and see that there is a bright red star in the sky right next to Alphecca, you will know that T CrB – the “Blaze Star” is once again Blazing in the night skies. Keep looking up and clear skies!
