Clear skies as astronomical twilight was passing, but transparency not too good and a very bright half moon in the south. Set up the LX90 with the 17mm Nagler to view some doubles. First viewed Saturn – very good details, could see space between rings and planet, but not ring separation. Moved to 24 Comae (SAO-100160), easy separation of the 20.3” separation, but didn’t discern any green tint to the secondary. Went to Alpha Herculis (Rasalgethi – SAO-102681), easily separated the 4.6” separation, but again no green tint. Used the 9mm Plossl eyepiece – still no green tint. Went back to the 17mm eyepiece. Later came back to Rasalgethi, transparency improved somewhat – primary star brighter yellow, and secondary did show a greenish tint as it shimmered. Made a sketch as it appeared to this observer.
Viewed other doubles in Hercules: Rho Herculis (RA 17hr 23.7min; Dec +37°08’), nice pair (Mag 4.5/5.5, 4.1” separation) – easily split; STF-2063 (RA 16hr 31.8min; Dec +45°35’); Mu Herculis (RA 17hr 46.5min; Dec +27°43’) wide split, but secondary is mag 9.5 – was finally able to see both stars; Kappa Herculis (SAO-101951) easy split – nice blue and yellow colors; 36+37 Herculis (RA 16hr 40.7min; Dec +04°13’) widely separated (69.8”), but nearly equal magnitude (6.0/6.5), blue and red colors. Moved back to Coma Berenices, and viewed ΣCRb (RA 16hr 14.7min; +33°51’), close together (6.2”), but nearly equal magnitudes (5.0/6.0) and easily separated. Viewed M-13 briefly before heavy clouds moved in from the south – shut it down about 10:45 pm.
