I was out last night using my 20" in my back yard (SQML 18.5), going through some pairs in CDSA. Seeing and transparency were both mediocre, so I was mostly using an 8" off axis mask (effective f/13). I came upon Met 9 in Coma Berenices and had this observation:
Met 9: 8" mask @ 205x, do not see any double. 8" mask @ 410x suspect elongation. 8" mask @ 667x see a fleeting, bluish point just outside of first diffraction ring. A star is light yellow orange and bright; 2 delta mag. to B. A feels elongated / egg shaped. At 20" and 667x the seeing is too messy though there is a knot in the diffraction where I had noticed the point with 8". Strong feeling A is elongated.
WDS: 12h 54m 39.98s +22° 06' 28.8" P.A. 51 sep 1.7 mag 5.70,7.77 Sp F8V+M2-3V dist. 33.85 pc (110.42 l.y.)
Stelle Doppie shows first measure in 2002 and slightly widening through the last measure in 2013 (due for a new measure -- hope Nucleophile sees this!)
Since there is no other than an AB pair shown I checked Aladin Lite. SIMBAD gives only one green box, HD 112196. But Gaia layer gives 2 green boxes which call out different coordinates. I don't know if this means there are two stars here? Also it seems there are two closely separated stars; may be there is a AC pair? It could just be the elongation I sensed was due to the seeing...
Appreciate those who can to observe and perhaps measure it. And I appreciate the help to interpret Aladin Lite.
Edited by mccarthymark, 19 June 2019 - 12:56 PM.