Thursday, August 01, 2019

a smack of doubles (Blue Mountains)

Prepared the Geoff Brown Observatory for viewing. Readied power. Cooled the big telescope. Dropped the south walls, for low targets in the south. Started TheSkyX.

8:29. The humidity was 76%, from the Davis weather station.

8:49 PM, Wednesday 31 July 2019. Went to Jupiter with the GSO RC 16-inch with the Tele Vue 27mm. Colourful. I could see two moons already.

Back to the 'scope.

Then three moons.

Realised SkyTools was not showing the current time. East was more or less up for me. Ganymede was about a half-planet-diameter away, to the east. ST3P said Callisto was the same side as Gany. Io was 3 or 4 times the distance, opposite. Europa beyond, almost double the distance.

I headed out to the Observing Pad to see how everyone was doing. Ian had his 20" Dob going. Jupiter was pretty fantastic. Cloud tops were amazing. We thought we saw a shadow transit. But my software wasn't showing it. Verified I had it set to real time...

[ed: Must have been a barge!]

Put on bug stuff.

9:06 PM. Shared the view with Wayne. We enjoyed the Jovian view.

Needed help to spot it naked eye. Encouraged Millie to stand behind Ian's Dob, like I did, to find it. Later, tagged Saturn in the south-east.

Considered μ (mu) Scorpii. Ha! SHT 72. I wondered who the discoverer was... [ed: Shatsky, N.I.]. Slewed to HD 151890.

At some point, I had added this object to my double star candidate list. Too low and too wide... It was on Lodriguss's naked eye list.

The telescope was nearly horizontal. The star's elevation was 6 degrees!

9:29. Noted a very wide pair. Oh, μ1 and μ2. Equal stars. Bright.

Extremely wide. Over 5 arc-minutes apart. Almost 6. With a PA of 72°. μ1 was to the right (or west) with μ2 to the left (east).

An interesting pattern of stars to the north.

There was strange stuff going on in SkyTools. The Object Information box indicated it was a triple. There were AB and AC buttons. The drop-down menu for the companions however only included A and C. When I clicked the AC button, it said the stars were 80.5" apart, at a position angle of 257°, and the magnitudes of the primary and tertiary stars were 3.0 and 9.6 respectively. When I clicked the AB button, no magnitude was listed. Sep 9.2", PA 210°. B was not shown in the chart.

C was supposed to be opposite μ2...

9:34. Tagged it. About 1/5th the sep. of μ1 and μ2. Yep. That was the C companion. Extremely faint. Mind you the sky was blue.

Alarm went off for the ISS pass... Did some prep for that.

9:54. Returned to the Warm Room after the camera-mount setup. Looked up the particulars of mu Sco. Checked the recent numbers from the official source, the Washington Double Star database:

SHT  72AB    2000    210   9.2  3.70  8.91 B1.5+B6.5
WFC 181AC    2016    257  80.6  2.97  9.41 B1.5+B6.5


B was brighter than C. But rather close to A. Should have been possible, I thought. [ed: Not like it is neglected...] Looked again. Nothing.

Steve came through briefly. Terse. Oh oh.

10:09. Ed was surprised how low the subject was. He said he saw something at the 2 o'clock position, very close but with a black gap. Oh. Maybe he saw it...

I headed outside for the ISS, to observe, to start the camera.

After the flyover, I returned to the GBO. Slewed to next target. HD 112733. Struve 1702. In Canes Venatici.

Risa popped in. She shared the lights were off in the SLO. Steve reported Risa could start her imaging.

10:31. Orange and blue stars. Subtle colours. Dim. Previously logged. Widely separated in the big 'scope; easily split in the small 'scope. Nearly equal brightness. Beside another bright pair: ah, Cor Caroli.

I had put in my candidate list. From the TLAO book. A keeper.

I heard exclamations from outside. Ian D saw a fireball.

Ed visited returned to the Warm Room. He had been staring at the head of Draco trying to pick of dim stars. According to Stellarium, he had reached 5.7. Shared my life list numbers, in particular, that Steve and I got to 6.4 at the CAO using stars in Ursa Minor. Coincidentally Steve wandered through.

Steve shared that the OBS software had crashed when they were almost done.

Went to next. Mused on sketching the scene. 25 CVn aka STF 1768. Yellow and orange.

Spotted the A and B stars with a separation of 1.8" despite bad seeing. Wow. Different magnitudes and close. Correction: SkyTools said they were 1.7" apart as of June 2019. A binary system drawing together.

10:44. Noted the mags of 4.8 and 7.1. This was on my candidate list but I wondered if it was too hard. Too tight and too different, needing a powerful large 'scope to get the A and B. A "box" of stars. The C, D, E, and F were doable in a big instrument. Some not visible in the TV 101. And still too wide.

Next. ξ (xi) Bootis. Nice. Orange. Triangle. Awesome. Fantastic colours. On a bunch of coloured lists. Steve had a look. He thought orange or yellow and white. Different magnitudes A and B: 4.5 and 7.1.

On my View Again list. A 150 year binary.

Tried to dig out the D partner. Got it. I could see mag 13 and 14 stars but not the C.

10:55 PM. Confirmed I got it. Checked the magnitude limit of the RC 16 telescope: 16.3. I estimated the star was in the 15 or 16 brightness range.

Checked my image of ξ Boo. Yep. C was very faint. Fainter than D.

Popped outside to inspect my camera. Dewed out. Chatted with Wayne briefly. He was noting the crazy humidity. Millie came round. Asked me where Dietmar was. Ian W and Steve chatted.

11:02. Should have brought the dew heaters... And I hadn't felt like bugging anyone.

Encouraged Ian to have a look at ξ Boo. He doesn't get jazzed by doubles...

I complained about TheSkyX. Issues with searching. Steve suggested in work in the Find tab as opposed to the Telescope tab. Finding it cold, Steve closed the outside observatory door. I complained about the focuser. Steve described it as being made of rubber bands. Risa said she was imaging.

Went to HR 5831 or STT 300 in Serpens Caput. Ah. Never viewed. Sep 15". Got tripped up in the software. Came from a colourful list. It was quite beautiful. Orange and aqua-green. Dim though. Steve thought one of the star's was purple. Big difference in magnitudes. Yes, 6.2 and 9.5.

11:17. It reminded him of a pair in Canes Venatici. [ed: He was thinking of Cor Caroli.]

We checked the weather conditions. Compared results. I refreshed the Davis weather page. Was 76% at 8:09. Now it was 83%. Dew point was 13.3°C. Air temperature was 16.3. Steve's on-board sensors said, 92%, dew point 10.7, air ambient 12°. I noted that the Davis sensor is in a different location now... Maybe there's a radiant heat factor? Pulled up the weather page for Clear Outside: 17°, dew 13°, 76%. Checked Astrospheric: 16° air and 11° dew. Good to Stargaze echoed the numbers. Environment Canada from the airport: 15.6°, 12.7°, 83%. We concurred, not as good as last night.

Steve dimmed the red lights. We talked about the pointing model for the Paramount ME. Working very well.

Tried the searching in TheSkyX on the Find tab. Better response.

11:31. Wondered why I put γ (gamma) Ser on my list. Very wide stars. Not terribly interesting in a telescope... Maybe best with binos.

Moved the 'scope. HD 144564 aka STF 2007. A triple.

11:33. We wondered at the colours. Smalt? White Atlantic blue perhaps?

Readied for HR 4917 or Struve 1695 in Ursa Major. Very nice. Need a bit of aperture to get the AB, at 3.8 arc-seconds. C was a mile away, at the 8 o'clock position. In a little football below (east). Yellow and orange in the big 'scope. I like it. It could be in my candidate list. Primary was K class.

Millie saw a meteor, her first one.

11:49. Turned on the baseboard heater.

Slewed to γ Her aka SHJ 227. Never observed. Holy cow! Millie and Ed had a look. "Orange and whitish? Orange and blue?" Millie said. Ed didn't think it was pure white. Worked in the TV101 although very dim. Millie helped Ed.

From a "most beautiful" list. Oh ho. Neat. Widely separated. Magnitudes were 3.8 and 9.8. A triple. Lots of field stars at high power. Interesting field, at high power. A and B were 43" apart. Millie said that B was "to the left?" Yes. "The main star was very bright." Yes.

I went back to find the third star. C was 3 times the distance. "Oh, that one!"

I spotted a star not in the software, at a right angle to the A and the B.

Noted a C-shape of stars below and right (east).

Millie retired.

I saw a star not in the software... Above A (north-west). At a right angle to A and B. About the same brightness as C. Er, dimmer. About the 12 o'clock position. ST3P said C was mag was 12.2.

Ed said he was seeing something but I couldn't understand his directions. Opposite B but closer. He went to have another look. Wondered if he was imaging it? "A beam of light?" Maybe a diffraction spike?

Distracted, I didn't think to sketch it...

12:00 AM, Thursday 1 August 2019. Tried looking it up in Aladin (in my custom quick look-up tool). Didn't work as the primary was too bright.

[ed: From the WDS...]

SHJ 227AB    2013   226  43.3  3.76 10.05 A9III   
DRS  58AD    2010    176   8.3  2.94  8.08 A9III   
SHJ 227BC    2015    298  82.1 10.05 13.31     

Unclear to me... Oh well...

Moved on to a non-double star. A small planetary nebula, NGC 6445, one of the Finest. On my View Again list. I changed eyepieces, increasing the power. Rectangular shape?

We have lots of LPR filters... Looked for the ionised oxygen filter. 2". It would not fit in the Tele Vue 27mm being out of round.

Asked Steve if I could borrow an eyepiece.

Found the 20mm ocular in our cabinet. The O-III dimmed the stars. Better contrast.

I pulled up some images from the interwebs. A little box. Wispy stuff around it. I found it in the TAC Eye Candy list. Also on my View Again list.

Fell into a different SkyTools list.

Jeff popped in, from the THO. Where's Waldo. He was doing some wide-field. Talked about his new Y-mask. He uses a jeweller's loupe on the back of his camera.

Steve checked the transparency. Jeff thought it could be better. Maybe smoke was a factor. Weather check: Davis, on the roof: no wind, 85% humidity, 16.5°C air. Steve's: 93%, 12° ambient, 11.1 dew.

Turned off room heater.

Slewed. A couple of doubles, but not the Double Double. HD 154510 aka STF 2120. Neat-o in the little 'scope. Ooh. With a little surprise! A keeper, a good one. In Hercules. Faint pair below (do the south) beyond the C star. Not an official pair according to ST3P. With GSC 02068-0695.

Ed asked which of the ice planets was up. Neptune was first, currently at 22° elevation; Uranus was behind and only 5°. Both in the muck, Toronto and Collingwood light domes.

12:45 AM. Sent the Paramount to Neptune. Noted the right-angle triangle of stars to the left or north. We could not see Triton. Set the time to now in SkyTools. Accommodated for the mirror diagonal. I simulated the view. Triton should have been below for us. 10" separation. Ed asked how big the planet was: 2". Oh. Mag 13.5. The software did not show the moon until a 5mm eyepiece was active! Weird. I saw stars in the field that were magnitude 13+. Verified sighting a 13.6 star.

Ed called it a night.

12:57. Decided to go after 56 Her. aka STF 2110. Not viewed. On the Coldfield list. Slewed. "Summer wheat and campfire ember!" Steve said he could visualise those colours. He hustled to the eyepiece. Ah, a G0 star. We talked about G2V stars. Easy split but very different magnitudes. I estimated 4. SkyTools said more than 4. Wow.

Next up: 21 Sgr. I could not split. Too close, too different. Also below the 2x. Should not be on my candidate list...

1:13. Viewed Arrakis, mu Draconis, was splittable in the small 'scope. Up and down. In-line, I had never seen the C star. A binary. Should be easier now. Grabbed a higher power eyepiece. North was straight up. C should have been at the 5 o'clock position. 6 times the separation. 2.5 vs 13.0". Back to the ocular.

I needed hot chocolate... In my mug.

Visited our member on the Pad. Imager.

1:30. For the Don't-Even-Bother Category. Could not find the C element. Next...

Risa dropped in with a couple of SLO questions. I asked her to fire up the dehumidifier. And to not install the telescope caps.

1:38. Orange and green. HD 169392 or STF 2313.


Went to M69, Messier 69. An object only viewed once before. Very faint. A smooth concentration of stars, this globular. Reasonably large. With a bright star nearby. The OTA was nearly horizontal... Wow. It dimmed the object. Shame. I guessed 7 atmospheres. [ed: SkyTools says 8.1.]

You know it is silly when the 'scope is pointed below horizontal. It was perfectly "cromulent," Steve suggested.

I took in HD 178211 or Struve 2455 in Vulpecula. I returned from telescope. White satin and crimson. "I gotta see this," Steve said.

He reported his on-board computer was reading 97% humidity.

Now yellow and blue with the 18mm. The bright star above or south-west HD 343742 was not related. No problem spotted faint C in the large OTA. Dimmer one was above, to the north-east. Noted a J-pattern. Checked for the C star in the small 'scope--nope, not possible.

2:00. Decided to look at Saturn. Nice view. Many moons visible. Some colour. Cassini Division easy. Different colours in the cloud bands, equatorial belt bright, lighter than the others. I wondered if I could see the C ring. Too bad Risa missed it... Dione and Titan visible to the east. Rhea opposite, in a curving arc. Nice.

Next: HR 7412 or SAO 124698. STF 2532 in the middle of Aquila. A quadruple from a "most beautiful" list. Very interesting. Lots of stars. I didn't see anything at first in the 101. Briefly visible with averted. In the 16-inch with the 18mm, obvious, gold and deep blue dim star. Widely separated. D was visible, 3 or 4 times the distance, opposite B. C formed an equilateral triangle with A and B, extremely dim. ST3P said it was mag 13.9. Noted high-13 stars to the south. Fantastic colours. Needs big aperture and/or high power.

It was late. Considered one more target...

Selected HD 200256 or HIP 103813 or Σ 2742. Dim. In Equuleus. Nearly equal, bottom one was slightly dimmer. Same colours. Easily split in the 18mm.

2:16. Parked the 'scope. Packed up, as much as possible.

Steve's rig was still running. Found him in the house.

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