Sunday, August 16, 2015

mostly coloured doubles (Blue Mountains)

Started and stopped the audio recorder this evening... To preserve space.

11:50 PM, Sat 15 Aug 2015. Wanted to look at some double stars.

Decided to try a new method, the "chart method" in SkyTools, working from the Interactive Atlas, as opposed to the list. I checked all my preferred targets in the list then displayed the IA with all the checked entries.

Chose ο (omicron) Ophiuchi (aka 39) from the RASC Coloured Doubles list. Really low, just above the horizon. Swimming. Just a simple double. Easy split. Orange and blue, I thought. About 1 or 2 magnitudes different. Bev had a look. The Observer's Handbook said it was orange and yellow. SkyTools 3 Pro said they were 1.6 magnitudes different. Viewed in both 'scopes. Splittable in the Tele Vue 101mm with a 10mm eyepiece, i.e. 54x. [ed: Haas says "tangerine orange and silvery white." I found it on View Again list, not sure why. Removed it.]

Bev asked about the orange star to the north-west, low. I guessed it was Arcturus. She thanked me for the star show.

I could hear people out on the Observing Pad.

Next target. A big hop. 41 Aquarii.

12:07 AM, Sun 16 Aug 2015. Warm yellow. Really hard to pick the colour of the secondary. Maybe pale blue or pale green. The A and B were obvious. RASC described the stars as yellow, blue, and very tight. [ed: Haas says yellowish peach and pale violet. Webb says reddish and blue.]

ST3P said it was a quad so I returned to the ocular to dig out the others. Checked the chart. Nailed 'em...

[ed: Not sure why, again, but 41 Aqr was already on my View Again list. I decided to leave it on, so to have another good look.]

"How's it going in here?" Sue and Chris V wandered in, along with some from the Kuan party, interested in the Dumbbell. I slewed to Messier 27 (M27). Talked about how many planetary nebulae showed lobes. Chris looked up the distances. While waiting, we spotted some meteors. And we talked about rainbows and unicorns. Again. The president popped in, asked if he could go in. Please do. I slewed to the next object. And edge-on galaxy. NGC 7331 (Caldwell 30). It did not look great. Bad transparency?

Ian W said there were not a lot of people outside. Wondered about packing up gear at the Observing Pad. He offered to bring in the Oberwerk binoculars. We considered leaving the 8-inch Dob and eyepiece case out.

Chris and I considered the NGC 7640, 7814, the Splinter. The Spindle? He said it was also known as Messier 102 (M102). ST3P showed it above the two airmass...

12:31 AM. Slewed. Odd. Way too low...

Oops. The M101-102 confusion. Slewed again in TheSky 6.

Went for WZ Cassiopeiae. Another target from the OH.

12:57. WZ was an incredible pair. A was an orange star and the B star beside it was blue. Fantastic colours. The RASC table says they are red and blue. ST3P shows A is a C-class star.

SkyTools said WZ was a four-star system. The designations were unusual with P and b (yes, lowercase) partners. I thought the small letters was for spectroscopic pairs... The system formed a spire with the P star (aka HD 240474) starting it off. Great colours.

ST3P also showed many pairs in the area... There was a faint pair due north (but unrelated stars) with TYC 04014-1721 1. And then there was another pair, with TYC 04014-1227 1, almost the same separation and orientation, a bit further away, and slightly west of the first faint pair. And then there was another pair, with PPM 11841, directly north-west this time, beyond the P star, same separation as the other faint pairs, but a different angle [ed: Known double, aka STI 1248]. I noted the line of three faint stars to the west, with TYC 04014-0621 1. And some bright stars to the west-south-west, including HD 224655. Interestingly, all the stars were similar brightnesses. Pretty neat. Wonderful stars in a rich field.

[ed: Not in Haas's book!]

I offered to hold doors as gear was moved in.

1:04. Chose HD 1429, aka Σ24 (Struve) for my next target.

Tony returned the Manfrotto tripod with squeeze-grip. Had a peek in the eyepiece. Noted an orange star. Still on WZ. "Amazing colours," I said. Chris had a look. I shared the stellar class info.

Slewed, finally.

1:10. HD 1429: yellow and blue. Very pale colours. My colours agreed with RASC and Haas. Very tight. Very similar intensities. Just barely detectable in the Tele Vue. And fainter.

I noted the triangle of faint stars to the north-east. And the fairly bright star (TYC 01733-0959 1) to the south.

Noted I was close to Almach... Slewed. Then increased the magnification. Headed out to the Observing Pad to see if I could get a better view in Ian's big Dob. Could not see the other components.

1:39. Once again, I found myself confused about this system... I would need to re-view.

2:16. γ1 (gamma) was the orange star; γ2 was the blue. D was much fainter. C was not possible, being far too close. Had another look in the C14 (with the 18mm). Tried to excavate the D star. Hrmm.

I could see GSC 02837-1813 at mag 14.7 on the way to TYC 02837-1793 1 mag 11.2 star. Both to the west. Both on the same side as the D star. ST3 said D was mag 15.0. Kind of frustrating. In terms of the coloured doubles objective, I've seen this target. But I really wanted to coax out another star...

Headed to 12 Ceti.

2:26. Yellow and blue. Or yellow and orange. Comes and goes! RASC said yellow and blue. [ed: Smyth is similar.] Could not split in the TV101.

ST3P said it was a triple. I saw the C star, at the right angle to A and B. Well away.

Noted the hockey stick of stars below or to the south-west. Awesome.

Wayne popped in. He faired well this evening. Got some good astro images. Figured out Parallel and PHD issues. Took notes. Good. The locking knob issue was sorted. Also jumped on the bandwagon and shot some aurora photos. He said the mozzies were bad, although not biting him. He asked me to keep an eye out for red light bars. Headed home.

Slewed to my next prey.

2:38. Could see a pair in the Tele Vue and Celestron. Fairly empty field.

I was not sure I was in the right area. Confirmed! HD 5780, aka Σ80: yellow and blue, in the C14. This matched the OH description. Orange and blue, in the TV101—first impression. Gould said "deep yellow and ashy." Right. Widely separated.

There was a dim, greyish star to the west. That was C, according to ST3P. Nearly a right angle to AB. Very wide. Easy.

A and B pointed to the bright star HD 5804 to the right or south-east.

Spotted a double star off to the left or north: BAL 949. Very faint. Blue stars. Nearly the same alignment as 5780 AB.

Oh. Near Uranus! Zipped over...

2:44. Fantastic colour, of course, in the Tele Vue. Near the bright triple of whitish stars.

The pale blue planet was south-west of a number of bright stars including HD 7542 (mag 9.5) and PPM 144413 (10.0). Didn't notice any moons...

The disc was obvious in the C14.

2:47. I might have seen Oberon. A bit surprised at how far away it was... ST3P noted the magnitude as 14.2. Then again, Titania was mag 14.0. But closer to its host.

I felt tired.

Pressed. 42 Piscium.

2:50. 42 Psc. Yellow and blue. Widely separated. Faint again. Very different magnitudes.

The RASC Observer's Handbook notes this pair as topaz and emerald. Well then. [ed: RASC appears to have drunk the same Kool-Aid as Haas. I decided to leave in my View Again... to have another chance to be impressed by the colours.]

I also spotted the faint star, in-line with A and B, GSC 00602-0772 at mag 14.9!

Noted the pair below (west), SAO 91862. Very faint. Tight.

Decided to view star 55, aka Σ46. A very short hop to the left. Perhaps 2 magnitudes different?

2:54. Nice pair. Very tight at 54x. Yellow and blue. Just a pair. ST3P said 5.4 and 8.6 therefore a delta of 3 mags. RASC said orange and blue and faint. Haas said citrus-orange and blue. Webb said "very yellow and very blue." Hartung said "orange yellow and ashy."

Going on 3 o'clock. I chose to close up. I was pretty happy with the progress, more RASC coloured doubles knocked down.

Shut down the observatory. Grabbed my sunglasses (for the morning) and the netbook.

3:02. Signed off.

I was really happy to chip away at a few more doubles...

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