naked eye magnitude: γ (gamma) Ursa Minor at 3.1
conditions: sporadic clouds, humid, mist, fog, oval track lights
Assembled the SP-C8 'scope as fast as I could to see Jupiter. Slowing things down a bit was that I had not yet realigned the finder scope. I skipped the alignment process for the time being. I also forget to attach the counterweights again so, like before, the telescope started to fall rapidly when I released the clamps. Gotta be careful about that. Don't rush!
Jupiter was very low above the horizon by the time we could get to it. But I could see, despite the glare from the oval race track lights, 2 moons (Io to the east and Callisto to the west) and the 2 dark middle bands. I invited Christine's Dad (Gary) to view it with me while his wife (Linda) unpacked their small telescope. He could not see the moons.
Diane was going to come down but she passed out.
Jonathon had dropped by at that point. So he took some looks too.
As it grew darker, I aligned the Celestron finder scope. I made sure the end piece with the cross-hairs was tight. And I focused the front objective of the finder scope, locking it in place with the silver ring. It is so nice having the finder scope perfectly aligned and focused.
Then I went for Ring Nebula (Messier 57 or M57). Nailed it quickly. That was the fastest ever!
It was rather faint. Again, not good conditions for deep sky.
Linda finally appeared with her telescope, an old red Tasco No. 13, I think, on a tiny equatorial mount and metal tripod. A cute little thing. She was calling it a catadioptric but it looks like a reflector to me. The strange little finder scope was out of alignment so I helped fix that. Eyepieces were 0.965"; she had two of them.
We chased some double stars. I started with Mizar and Alcor. Very pretty. Then I pulled out the Skymaps.com listing for September and reviewed the Telescopic Objects list.
η (eta) Cassiopeiae was wonderful. The description said, yellow star mag 3.4 and orange star mag 7.5, sep=12". Both Jane and I felt that the yellow star had a slight green tint to it. The Belmont Society double star list says that Achird is a gold and purple double 12.2" apart. Purple?! I'm starting to trust this list less and less...Is it my imagination? The yellow-green star seemed much bigger than the orange, i.e. that it had a disc, not a point. Is that possible, could I see that?!
Albireo, β (beta) Cygni, was also wonderful. Skymap says, beautiful double star, contrasting colours of orange and blue-green, sep=34". Right on. The blue-green was very interesting. Belmont reports it as gold and blue. Delightful.Tried to find 61 Cygni. But my finder scope view did not correspond to my SkyAtlas chart. After a lot of back and forth, I suddenly discovered I was centred on the wrong star to begin my star hopping. But at that point I was tired, frustrated with a target directly overhead, and the sky was not cooperating. Similary, Linda was discouraged as her objective was coated with dew.
As we wrapped up, I talked about dew fighting strategies.
Funny. Even though we didn't do a lot I was satisfied. I had helped out some people again. I had properly aligned my finder scope. And focused it correctly—for the first time. And I had found a couple of new and colourful double stars!
Christine never came out of the camper to observe...
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On reviewing my notes, I realised I really messed up with 61 Cygni! Initially I was centred on epsilon but I thought I was looking at sigma (which I was also misreading as δ (delta) and getting confused by the brightness scale). I did correctly ascertain that I was in too close to the centreline of Cygnus. But at the time, I thought I had been looking at ν (nu) instead of σ (sigma). Now it turns out I was too low as well! I had actually moved from ε (epsilon) out to ζ (zeta). I should have realised this when things still weren't looking right. I had completely misread my chart. I was also tripped up by SkyAtlas's use of sigma. Oh well. I'll know better next time.
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