Over the last week we have had a couple of occasions when the sky has been clear enough for a while for me to get out and observe some variable stars. Last Saturday (7th October) I had just long enough to observe GO Pegasi before the murk closed in. That night the moon was 1 day past last quarter and not due to rise until 22:39 UT. Darkness is now falling earlier in the evening and astronomical twilight ended at 19:20 UT on that day. At 21:55 UT there was some hazy cloud around and some parts of the sky were obscured, however, the constellation of Pegasus was pretty clear and I was able to determine that GO was fainter than star B (=7.0 mag.) on BAA chart 103.02 but brighter than star E (=7.8 mag.). It was closer in brightness to star E and my estimate was B(3)V(5)E which made it magnitude 7.3.
This star doesn't have much of a range in magnitude variation (just 0.77 according to the BAAVSS) and, probably because of this, it doesn't appear on the list of beginner's variable stars as described by them. But then there are no beginner binocular variable stars listed in Pegasus, which seems a shame, and this is why I think I picked this one out of the BAAVSS observation program for pulsating stars. I say a shame because Pegasus is well placed at this time of year and is a prominent constellation in the sky. After a recent run of being around magnitude 7.6 it has brightened recently to 7.2 or 7.3 (near the maximum of its range of brightness) and I am glad to say that I am not the only BAA observer to have recorded this! The last time it reached this magnitude was back at the beginning of the year over 280 days ago. This seems a bit odd for a star that supposedly has a period of 79 days! However, I have found a paper by Kate Blackham (pdf) where she can't find any periodicity in this star and has declared it to be an irregular.
Two days ago on the 9th October we had another evening when there was a brief period of clear weather. Again there was quite a bit of hazy cloud and one or two more thicker patches of accumulation. The variable star TX Draconis is now heading down towards the west in the evenings but it is still at a good altitude. At 21:12 UT TX was fainter than star K (=7.0 mag.) on BAA chart 106.04 but brighter than N (=7.7 mag.). My estimate was K(5)V(2)N which made it magnitude 7.5. Another observer at the BAA on the same night estimated it to be visual magnitude 7.3, so we are in reasonable agreement. I had been intending to look at AH Draconis as well but by then a bit of cloud was obscuring my view.
I went on to look at RW Cephei which I have described before. At 21:36 RW was fainter than star P (=6.2 mag.) on chart 312.02 but brighter than star E (=7.3 mag.). My estimate put it midway in brightness between the two, namely B(1)V(1)E making it magnitude 6.9. This star hasn't changed much in brightness by my reckoning since I last looked at it on September 12th. Then I estimated to be 6.8. I think these results are in pretty good agreement with other observations from the BAA and AAVSO.
All text and images © Duncan Hale-Sutton 2023
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