Date Time: November 17, 2019 1900-2330hrs
Weather: Cool, -5C, no wind to breezy later on with an easterly wind, cloudy at times, hazy, with some partly clear periods.
Attendance: David McCashion
Equipment: Canadian Telescopes 80 mm ED/APO on tracking mount. Meade LX200. Canon Rebel t3i using telescopes at prime focus. Deep Sky Tracker and PhotoShop used for processing.
Objective: RASC NB posted a notice that the Algol minimum was at 1928hrs, I decided to make an observation attempt where I could show the difference in magnitudes for the variable star.
Report:
- Went out at 1920hrs to visually observe Algol, and it was noticeably fainter than normal, but wasn't able to start imaging till 2135. By the time I started imaging, the star seemed much brighter. The star drops from +2.1 mag to +3.4, for about 9 hrs once every 2 days, 20 hours and 49 minutes due to another star that passes in front of and behind it.
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| 13 images stacked for about 8 minutes of elapsed time. ISO 800, approximately 40 seconds each. |
- Richard Hinckley Allen, in his book, Star Names Their Lore and Meaning describes Algol thus, "Beta Persei, Spectroscopic binary and variable, 2.3 to 3.5, white. Algol, the Demon, the Demon Star, and the Blinking Demon, from the Arabians Ras al Ghul, the Demon's Head..." He describes the variability as thus, "...and it has certainly been one of the best observed, as the most noteworthy variable in the Northern Sky. It" continues sensibly constant at 2.3 magnitude during 2 1/2 days, then decreases, at first gradually, and afterward with increasing rapidity, to 3.5 magnitude"; ITS LIGHT OSCILLATIONS OCCUPYING ABOUT NINE HOURS; its total period being stated as 2 day 20 hour 48 minute 55 second."
- By 2230hrs the waning gibbous moon started to rise in the NE, which was odd, because normally I notice the moon rise in the SE. Clouds were in that part of the sky for the first hour of its rise, but the brightness cut right through clouds.
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| Single shot 1/50 second, ISO 200 using Meade LX 200 at prime focus. |
- Wind started picking up after 2320hrs, from the east.
- No satellites or shooting stars were seen, even though the Leonid meteor shower was due to peak at 0200hs.
NOTE: I intend to do follow up observations to better understand how this stars variability works, including images that I hope will capture it at its normal magnitude and also an image that shows it at its diminished magnitude. I expect this might take a while, with the weather like it is, so, watch for updates!
