Caroline's Rose isn't in the Messier catalogue, and I became interested in it while playing with long exposures of constellations with my 50mm lens, noticing it as a dense smudge of stars. I first imaged it a year ago while collecting data for the
Double Cluster in Perseus, for which I had already rotated my camera 90 degrees. I only collected one hour before the clouds rolled in, so I set it aside to add more time to in the future.
I came back to it in 2022 just before I packed up my astrophotography gear prior to moving. I knew I wanted three more hours, and I got my wish. While stacking (and packing) I noticed satellite trails - oops! I'd forgotten to turn off rejection! I stacked again and blinked between the two stacks and was surprised to see one little red star blinking on and (almost) off. Had I discovered a nova?
Nope. WY Cas, an s-type variable star. Neat! I have included an annotated version showing stacks from each separate year. It has a period of roughly 18 months, and my imaging sessions were 12 months apart, so there is a fair amount of contrast in the magnitude. At its brightest, WY Cas is magnitude 7, while at its dimmest it is magnitude 14. It is a Mira variable, and is pulsating due to contraction and expansion. This in turn causes temperature fluctuations, which contributes to the changes in luminosity.
I don't really see the rose in this object, but it's one of my favourites nonetheless.
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