Saturday, June 23, 2012

stayed home (Toronto)

I had turned down Phil's invite to join the gang at the Long Sault. Also, I was not convinced the skies would be great... I still had, for the multi-night clear-run, the telescope set up on the deck. Ready to go. I'd be able to do a very rapid start up. And I was really looking forward to that!

9:25 PM, June 22, 2012. Spotted the crescent Moon from the office window. But I could not see it from the deck, unfortunately. I wondered about earthshine but then it seemed too bright right now...

Used Stellarium to check the position of Mercury. It was almost level with the Moon! But that meant quite far to the north. And behind trees... sadly. Frickin' trees!

10:10 PM. Moved the netbook in the kitchen...

Checked the weather conditions. Mainly clear, 21°C. Observed at Toronto Pearson Int'l Airport. As of 10:00 PM. Pressure: 101.3 kPa and rising. Visibility: 24 km. Temperature: 20.6°C. Dewpoint: 9.2°C. Humidity: 48 %. Wind: NW 18 km/h. The forecast: Clearing early this evening. Wind northwest 20 km/h gusting to 40 becoming light this evening. Low 16.

Tonight's experiment was to review my drift alignment instructions.

Step one: find a star near the meridian. And the ecliptic. Here we go...

10:39. I was trying to find a candidate star though the tree branches and leaves. At first I thought was at Yed Prior in Ophiuchus; no, after carefully reviewing the charts in SkyTools 3, I confirmed I was centered on μ (mu) Serpentis. OK. Considered θ (theta) Librae, further down, closer to the ecliptic. Finally, I settled on 47 Lib, nearly on the path of the planets.

It occurred to me that it takes some time to find these stars, in the city, with trees in full foliage. So it's probably a good idea to consider a target a little east of the meridian so that by the time you figure things out (with a push-to 'scope) it will be at the meridian...

With the eyepiece pointing up, and me looking down, I knew the field orientation. West was to the left; east was right. And, of course, north was up; south down.

I observed the star drifting north... So that meant the polar axis is too far west. I dialed out a bit. Ready for the next step, a target star in the east.

11:50. I could not get my bearings in the eastern sky—trees, leaves, branches in the foreground, few bright stars to choose from—so just randomly chose a star. I had the reticule aligned. I watched for north-south drift. Initially it looked OK.

11:54. Now I noticed slight northward movement. So I dropped the altitude a bit. And I thought "that's good enough." Touched up my notes. And now I was ready to do some observing.

11:57. I saw Saturn was in the clouds...

12:33 AM, June 23, 2012. I caught myself chasing stars in unknown, unfamiliar parts of the sky. And realised it was stupid. Just wasting time.

12:56 AM. Just heard a mozzie. Shoo.

I went chasing HD 172712 aka Σ2368 (Struve). I found it on my life list but with a note to revisit.

Interesting. I think I observed that LT Dra was not visible. Was this variable star in a dim phase? Did I check it when not visible!? Could it be below mag 12? Perhaps I should report it...

1:05. Initially looked at HR 7028. I decided to bump the power. But I think the seeing degraded.

1:09. I split Σ2368 with the 26mm in moments of good seeing. The stars seemed equal in colour. Their brightnesses were similar. Perhaps the south-east star was a little fainter?

1:16. It was easily split with the 9mm. I could also see the C star. It was almost inline with GSC 03539-2451 (mag 12) to the north and GSC 03539-0977 to the south. I thought the stars white, no colour per se. I estimated the PA to be 145°. Sweet. I can change the status of this item on my double star life list.

I noted TYC 03539-1736 1, a 12.1 mag star, in the field. That impressed me.

1:36. I returned to LT. Viewed it with the 9mm. It was bright actually. Brighter than TYC 03539-1694 1, at mag 10.1, and TYC 03539-1479 1, at mag 10.1. Huh. Where did those mag numbers come from? In fact, it was slightly brighter, by a hair, than HD 172268. Ooh, that's a variable as well...

1:47. I saw more high, thin cloud.

2:23. Went for R Cygni, from TLAO book. It is right beside θ Cyg. I noticed a small asterism not unlike Sagitta with HR 7465 and SAO 31823. R was a light orangey colour. theta is a bright yellow star.

In SkyTools, I noted that θ Cyg is a multi-star system. I saw the C and D stars with the 26mm and later the C star, at magnitude 10.6. ST3 says D is 12.4. That would be quite good if that magnitude rating was correct (although I've gone deeper on other nights). HR 7465 is the same colour as theta, perhaps lighter, closer to white.

R Cygni was slightly fainter than HR 7465 which is mag 6.5. Wow. I learned that R Cyg drops to 14 over a 1.3 year cycle. So I've caught it while very bright! Indeed: Turn Left at Orion says "A good part of the time it is too dim to be seen in anything less than a 10-inch telescope." I guess I'm lucky.

I also found it interesting to note that SAO 31823 is a double companion to R Cyg. It is dull, pale star, perhaps with a hint of slate blue.

Well, that was neat. One more off the list. A list or two. And lots of interesting stuff going on. 10 items to go on the TLAO summer list.

2:39. So just when I was thinking all was smooth sailing, the tracking went wobbly. Still, it was amazing to me that the little C battery pack worked 2 nights in a row!

2:43. Checked the EC weather report at PIA again. Observed at 2:00. Partly cloudy, 101.4 kPa and rising, visibility 24 km, 16.8°C, dewpoint 10.4°C, 66 %, wind NW 15 km/h. I thought, on the porch, it cool with no dew. A nice night. Except for those clouds!

I hope that lads fared well at LSCA. But I was glad I stayed home in these mediocre conditions. Not driving to and fro. And enjoyed some quality time with kitty. I think he found it very interesting to explore the deck at night. And I was pleased with the experimentation tonight. The polar alignment was good. The portable battery pack impressed.

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