Hello everybody.
So here I am again seeking out some amazing double stars and other very impressive and unusual stars in Cassiopeia with my William Optics 158 mm F/7 apochromatic refractor in my back garden on Saturday 21st August 2021. It had been raining all day and I was humming and hawing whether I should set up my refractor or not. The weather people had promised clear skies after sunset which had occurred at 20.39 local time. So often they have been wrong, but this time they were spot on! So after evening dinner I stepped out in the 12˚ Celsius warm night to have some huge fun hunting down these sublime celestial objects. There was a gentle breeze of 13 km/h which kept the dew far far away.
Having observed Arcturus and its optical companion CN Bootis, splitting Izar at 112X yet again and seeing Polaris B ridiculously easy at a mere 40X I knew straight away the sky conditions were going to be excellent – to put it mildly. It was now time to study some brilliant stars in the “W” near Beta Cassiopeiae (Caph).
1. I start off with 2 stars neither of which are double stars. TYC 3665 1359 is a single star which has a spectral class of K7 and has a magnitude of 8.2. My apo refractor loves to kill false colours and makes each of these stars almond brown any time I see them. This star most certainly has that strong brown hue rather than simply orange. At 40X and 112X the colour was to the fore.
2. Very nearby there is another K7 class star called TYC 3666 675 which is slightly fainter at magnitude 8.9. But it looks delightful all the same at 40X and 112X. I do plan to observe other K7 stars when the opportunity arises. It seems Cassiopeia has a good number of them.
3. Next up is my 20th carbon star in Cassiopeia and it has the designation FR Cassiopeiae. It is also known as GSC 03665-00350 or TYC 3665-350-1. The Right Ascension is 00h 22m 26.82”. The Declination is +59˚ 11m 33.52”. Its spectral class is C6 and its magnitude is 10.4. There is a 10.7 magnitude orange star right next to it whose designation is TYC 3665 1921. At no time could I see either star at 40X. But all came very good at 112X. FR Cas is a fairly good and reasonably rich orange star and it doesn’t appear to be a variable star despite its 2-capital-letter (FR) designation. Maybe it once was. But over on
www.aavso.org
there is one avid observer who simply states that the star varies from 10.3 down to 10.6 at various times over the last 15 years so clearly it hasn't varied by much. Perhaps it was a variable star when it was discovered allegedly by the astronomer German Cuno Hoffmeister in 1943. His name appears on
www.aavso.org
. It’s my 106th observed carbon star. Without hesitation I recommend it to you all for those who love these types of stars.
4. What a real privilege it truly is to go back and re-observe a double star I successfully separated in September 2020. KR 4 is an uncertain double star whose magnitudes are: A = 8.2. B = 9.4. Sep = 2.2”. PA = 180˚. In 2020 I required 225X to see a black gap between the 2 stars. But on Saturday night I had no difficulty splitting KR 4 at a mere 112X! I must say the view was intensely beautiful. I did increase to 140X and 167X of course. I found A to be a yellow-white F0 star. While B was white. My seeing conditions must have been not so great in 2020. I was completely astounded by the sheer beauty of this double. KR stands for Adalbert Kruger (1832-1896).
5. Finally I come to an amazing and seemingly difficult double star which I failed miserably to separate during the autumn of 2020. STT 1 is an uncertain double star with magnitudes: A = 7.5. B = 9.5. Sep = 1.6”. PA = 212˚. It sits very near to the wonderful triple star STF 3053. Fred on
www.cloudynights.com
issued me a personal challenge to revisit STT 1. I simply don’t understand why it would not split for me last time. But I have waited patiently to give it another go and I had already discovered my sky was exceedingly good this time round. Considering a full delta magnitude of 2 and a separation of 1.6” I was greatly surprised I could see the secondary touching the primary at 112X. Complete separation was to be had at 140X with my trusty TMB 8mm eyepiece. I spoiled myself further at 167X and 225X. The 2 stars revealed their whiteness without any problem whatsoever with a splendid and tiny amount of black space within these stunning jewels!
Thank you for reading this report.
Comments, questions and corrections are very welcome.
Clear skies to you all from Aubrey.
