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A Variable interest in Astronomy...
By Jeff Oaster
Posted on 4/26/2018 5:44 PM
Two years ago I decided to take on the Astronomical League's Binocular Variable Star program. I was amazed at how quickly I fulfilled the requirements: Observe, record and submit to the American Association of Variable Star Observers (AAVSO) the data of at least 60 total observations of 15 different variable stars. It was an extremely gratifying certificate to earn as it really helped me fine tune my observing skills while simultaneously doing contributing to the scientific community.

After a bit of an observing slump thanks to a year that saw me switch jobs while also neediing two knee surgeries, I picked up the observing again full-throttle. Since September, I have observed approximately 200 more variables of a wide variety of types and currently sit at 261. Along the way, I surprisingly received a certificate from the AAVSO for making 100 observations. I'll earn the next one at 1000!

While not the most sexy form of astronomy, variable star observing is strangely addicting, and certain stars that I observe regularly feel like they've become somewhat of an "old friend." It also does not require dark skies and once you get really familiar with some of your regulars, it barely even requires a star chart (I still use them every time for the comparison stars magnitudes). Yet it is still very challenging: Estimating a star's magnitude by simply comparing it to some nearby stars can sometimes be frustrating, especially when you notice that your observation doesn't agree with some of the other recorded observations. (They do double-check the observations. I recently had to delete a pair of observations that were over a whole order a magnitude off from similar recordings.)

Another fun thing is that neat little asterisms get noticed. I've recently started following the short period (roughly 3.5 day) variable U Cepheus and their is a roughly 6th magnitude "arrow" that almost points directly to it. TV Pisces has a micro-dipper in the same field of view. Better yet, the very cool R Scutum (with varying minima) is right next to the Wild Duck Cluster. Another star in Serpens - one that, curiously enough, has never been logged prior to my first two viewings of it - has an easily identifiable triangle that points to it (with the added bonus of the target star being surrounded by comparison stars that all match the range of its magnitude).

Sure, there are limitations. Because I use binoculars, I am limited to stars that peak around magnitude 8 since most of my observations are from my very light polluted deck. Also, overhead stars can get a bit challenging, especially since I tend to use my heavier 16x70s most of the time. Handholding binoculars is not recommended for this task! 

It seems like the AAVSO would like some more visual observers and if anyone wants to give it a try, let me know. The charts give you locations of the stars so it would be likely be pretty easy with a telescope. It may go without saying, but I love the challenge of doing it all with binoculars. Not only does the wide field of view makes comparisons (IMO) much more simple, but the notion of starhopping to explore the skies is so enjoyable to me.

As you may have guessed, variable observing has become quite a passion of mine. If you're interested in giving it a shot I would love to help you get started and hopefully help you avoid some of the mistakes I made in my earlier days. 

Clear Skies!