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A huge thank you to the Power Workers Union (PWU -Bruce Power) for their generous donation.

The money was used to purchase an ZWO ASIAIR. Here is the ASIAIR and a couple images the Bluewater Astronomical Society was able to take using the new ASIAIR.

1. ASIAIR mounted on the club telescope

2. Andromeda Galaxy

3. Trifid Nebula

THANK YOU VERY MUCH. The ASIAIR will be used extensively in all our outreach and children’s programs!

Recurrent Nova - T Corona Borealis - by Brett Tatton

A familiar northern constellation should briefly take on a different appearance at some point in the next couple of days, weeks or possibly months. The constellation in question is Corona Borealis and the star to watch out for is the normally unassuming star T Corona Borealis, aka the ‘Blaze Star’ or more simply T CrB.

T CrB is generally at a quiescent +10th magnitude, barely discernible with binoculars… but once every 80 years, the star has been observed to flare up to naked eye visibility at around +2nd magnitude.

T CrB was first observed to go nova in 1866. The second recorded flare-up of the star occured in 1946. A recent study from 2023 suggests that a bright ‘guest star’ seen in 1217 and again in 1787 may have been apparitions of T CrB.

T Coronae Borealis is what’s known as a recurrent nova. Less than 10 such star systems are known of in our galaxy.

A recurrent nova occurs when a white dwarf star orbiting a red giant star siphons off material from the bigger star. This material is mostly hydrogen and it envelopes the smaller star in an ever thickening layer until a point of critical mass is reached. The resulting fusion event is truly cataclysmic but somewhat brief.

When T CrB flares up it will brighten to about the second magnitude or similar in brightness to Polaris. It will also be a close match for the constellation's alpha star, Alphecca. Alphecca is magnitude 2.2. We can expect the flare up to last for several days after which the star gradually subsides to its double digit dim self.

We're encouraging folks to locate the spot in the sky now and to monitor periodically for the expected flare up. If you have never observed a nova star before then this event is an ideal opportunity to add "observed a nova" to your list of accomplishments!

There are links below that will take you to star charts of the area to watch. These charts are from the AAVSO (American Association of Variable Star Observers). This organization, comprising many amateur astronomers and professionals alike, collects valuable scientific data on variable stars. The association is known for their very fine star charts. The charts linked depict closer and closer views of the region. You could even use the charts to assist you in identifying the now quiescent star system.

T CrB is currently at magnitude +12. It dimmed from +10 during the summer of 2023. A similar dimming occurred a year of so prior to the 1946 apparition