It has been a long time since I was able to get in a little observing time. Although the temps were in the low 20's I bundled up and setup my 90mm APO here at the observatory for some good old fashion observing. The skies were transparent as the NELM was 4.4 magnitude but seeing was about a 3 for the night.
My first target for the night was of course Jupiter. The image of the giant planet was striking during those moments of steady seeing. This was the first time I viewed any planet with this telescope and I was hoping it would perform as I expected as this is my first apochromatic refactor. I was not disappointed. The chromatic aberration (CA) was virtually non-existent even at 104x. Quite impressive since this telescope is only an apochromatic doublet, I expected a little CA but didn't notice it. So, at 104x the North Equatorial Belt (NEB) and South Equatorial Belt (SEB) were very prominent as was some shading in both polar regions. During those moments of steady seeing I could make out a few additional features on the surface. I dropped the power down to 70x and noted the positions on the four Galilean Moons. In the eyepiece from East to West at about 11:20 EST, Callisto, Europa, Io, Jupiter, Ganymede.
Next target, NGC 869 & NGC 884, the Double Cluster. I have look at this cluster pairing many times and it still impresses me every time. The best way to view these clusters is with a low power, wide field eyepiece. At 24x both clusters fill the FOV. My eye is always drawn to the single red star situated midway between the two cluster. The only reference I have found to this star is an identifier from the UCAC4 catalog which is UCAC4-736-025735. I think this is a red giant star associated with NGC 884. The visual magnitude is 8.9 with a color index of 1.48 which makes it an M class star on the H-R Diagram. I just wonder how much of the reddening that we see is characterized by color excess due to interstellar extinction. Look closely at the two clusters and you'll notice that NGC 884 has quite a few more red stars then NGC 869.
One more target for the night. Tr 3 (Trumpler 3). This is a much overlooked open cluster in Cassiopeia and probably for good reason. A small telescope at moderate power (70x) reveals only a hand full of stars ranging from magnitude 8.9 to 12.3. The listed magnitude for Tr 3 is 7.0 and spans some 23' (arc minutes). I count about 12 stars at 70x. The cluster is very sparse with no concentration toward the center.
That it for this night. I closed out the log book at 12:50 AM EST. It really felt good to get back out under the stars again. I'm looking forward to more observing in the coming week. Comet ISON is on the list later this week. I'll leave a little early for work and try to view it with my 10x50 binos.
Clear Skies everybody!