Good evening, one and all.
Monday night 9th December 2019 was gloriously clear with no wind on the east coast of Ireland with very good seeing in my Bortle 8 or 9 in my back garden.
So I set up my William Optics 158 mm apochromatic refractor and the William Optics 70 mm on the Berlebach Planet altazimuth tripod good and early. Mirror diagonals are fitted to both scopes.
Sunset occurred at 16.06 local time.
Before I get to Cassiopeia, I did find Vega at 16.15 high in the western sky. Then I split Epsilon 1,2 Lyrae almost directly above Vega into 4 components at 112X at 16.20. Even at that time, Vega was still invisible! Lastly at 16.45 I could see Polaris A and B at 40X and 112X.
Now onto Cassiopeia. And I was specifically observing near the south eastern corner of the great W.
Each of the figures come from www.stelledoppie.it
1. Iota Cassiopeiae was wonderfully split at 112X as usual. The magnitudes are 4.6, 6.9 and 9.1. The separations are 2.6" & 6.7". The PA's are 227 and 117 degrees. Both A and B are white. C is blue - white.
2. ARY 35 is easily split at 40X. The magnitudes are the other way round. 8.2 & 7.6. The separation is a whopping 115.4". The PA is 133 degrees. It is a handy optical double as it leads me to other doubles. ARY stands for R.W. Argyle. The colours are blue - white and white.
3. Stf 282 is supremely tight at 40X. Both stars are almost identical in magnitude. I have rounded them to 9.5. The separation is 6.7". The PA is 295 degrees. They both "point" upwards in my eyepieces. 112X is very good too.The primary is yellow. B is white. It is a true binary.
4. CTT 3 is easily split at 40X. The magnitudes are 7.8 & 8.3. The separation is 88.1". The PA is 88 degrees. Both stars are white. It is an optical double. CTT stands for J. -F. Courtot.
5. STTA 28 is also easily split at 40X. The magnitudes are 6.6 & 7.6. The separation is 67.9". The PA is 148 degrees. A is blue white. B is white. It is a true binary.
6. HJ 1122 is a difficult split at 40X. Hard concentration is required. It is much better at 112X. The magnitudes are 9.6 & 10.3. The separation is 10.2". The PA is 217 degrees. It is a true binary.
7. Stf 302 is only magnificent!. The magnitudes are 7.5 & 10.4. The separation is 5.3". The PA is 170 degrees. Surprisingly it might not be a true binary. The A star is blue white. I got a tight split at 112X. The B star looks like a divot.
8. Stf 284 is a reasonably difficult triple at 40X. The magnitudes are 7.9, 9.9 & 10.5. The separation are 6.9" and 53.1". The PA's are 191 and 10 degrees. 112X makes matters much better. All 3 stars are optical.The primary is blue - white. The other 2 stars are white.
9. Stf 283 is another magnificent showpiece!. The magnitudes are 8.4 & 9. The separation is 1.8". The PA is 210 degrees. The G8 primary is a very rich yellow. B is white. I did split it at 112X and 140X. But I noticed how good the colour of that primary was at 167X. Give it a go!
Thank you for reading.
Comments are always welcome.