Sunday, March 01, 2009

very cold observing (Toronto)

Got lots done tonight! Some new and exciting double stars, got to know the neighbours, bit of show-and-tell for the neighbours, couple of Messier favourites, some planets and moons, did the best sketch yet of λ (lambda) Orionis, and participated in my first official asteroid occultation (a miss). But it was bloody cold...


I don't remember when the whole plan started to form. It must have been some time on Thursday or Friday as I looked at the weekend weather reports and saw clear skies predicted. Feeling optimistic I thought I could get some back-to-back observing nights in. That said, I already had an event Friday night, not one I was going to cancel. So Saturday would be the "big night" then, for astronomy! And maybe Sunday too? I considered a quick pack in case I wanted to reset for Sunday night.

Not that I need any help in the matter but I was able to sleep in a bit Friday morning. That would benefit me gaming Friday night. I could repeat that sleep shifting, staying in bed Saturday morning too, and then I'd be primed for Saturday night. But for some reason, I woke around 7:00 AM. I tried to fall back asleep. Alas.

Something of an unknown quantity was if Malcolm needed my help for repairing his car on Monday. When he called me live on Saturday afternoon suggesting he could drop the car directly, that relieved me of early morning duties.

So, I started to ramp up Saturday afternoon. Added asteroid (51222) 2000 JE24 to Stellarium. Reviewed my session pre-flight check list. Slowly began the assembly of the tripod and mount. Put the tube outside for a long cool down. Red lights on. New red light bulb to the garage. One of the big things I wanted to get a good handle on was light. Light pollution? Light interference?


I phoned Diane and Mark, neighbours to the west, ground level. Diane answered. I asked if they could keep lights down at the back of their house. She said they would be happy to oblige. I encouraged them to pop outside with the kids. I would have some RASC star finders on hand...

I phoned Lise and Don, neighbours to the west, upper level. Left a message. Don called back a little while later. They would be very happy to keep lights off. He said he was "intrigued," he had noticed me outside at other times. Nice! Some good bridge building there. I've never officially met them until now.

Visited the top floor of the house and spoke to Brian. He said he'd take care of the lights at the back of the house.

Phoned the middle floor and left a message. Kris didn't answer his cell. Looks like he was away anyway.

Phoned the Chernys. No answer again. Looks like they're definitely gone for the weekend. The back yard was lit up last night. Presumably the same thing would happen again. I considered putting up a tarp on the fence to serve as a light shield. But I forgot to do that in the afternoon.


Another objective for the evening was to make sure the hand warmer worked! I'd need it tonight. I revised my pre-flight check list, incorporating some new cues. And after dinner, as the sky darkened, I filled up the fuel cell so it was soaking, and then lit the burner. It took a long time to fire up, maybe 30 to 45 seconds of continous flame, but then it was good. In fact, it worked great for the rest of the evening.

It was still running long after I had come in for the evening. That was over 7 hours!


I was outside at 7-ish doing final preparations. I could see Polaris so I wanted to complete the alignment of the mount. Weird. From where I had set and leveled the tripod, I could not see alpha. Huh? Oh well. I just eyeballed it. I suspected it would be fine.

At 7:07 PM, I noticed a satellite. It was moving from south to north, between Ursa Minor and Casseiopeia. I just caught a little bit of it. It was medium brightness, brighter than Polaris. Possibly Cosmos 1766?

Venus was very pleasing in the dark sky. It was fun finding it in the day. But somehow it is more dramatic in high contrast. I thought about the "ashen light" that some report. I wonder if there's anything to it, or if it's a mental trick, or brains filling in details as an optical illusion.

The Moon was bright even though a fairly thin waxing crescent. I didn't want to look at it through the 'scope as I began to protect my night vision.

I thought my activities might attract the attention of Diane and Mark but I did not see them over the course of the evening...

I found the Cherny's damn lights on again. The one just under the roof overhang, I just realised, in fact trepasses into our yard. It goes over there tall fence into our driveway. That's not right. It's clearly on a timer but not a motion sensor.

From my garage, I grabbed one of my green camping tarps. From the car, I grabbed the box of bungees. I strapped the tarp to the fence between our back yards. It successfully blocked the light coming from their porch light through the fence slates. The upper light is a problem though... I'm going to have to talk to them about fixing this. I do not want to have to deal with this again. Take 'em a light pollution brochure?

An upstairs house light was on. Steadily. I couldn't see anyone about. I had to remind Brian to shut it off. He immediately extinguished it. Much better! Thank you!

According to the Oregon Scientific (OS) weather station, it was 9:02 PM. Initially I misread this: it was still set to summer time. It was much later that I figured this out. The weather station reported 50% humidity and -8.5°C. I had remembered to check the dew point for this evening: -18. Brrr. The predicted low was -15. I was finally ready to go!


OK. Let's have some fun. It was as dark in the back as I was going to get it. I had over 3 hours to play before the occultation. I had a new working (rendition, formatting?) of the Sky & Tel's winter double star list, sorted by constellation. I looked for a target. I considered objects in Andromeda but she was setting behind the coniferous. So, Aries then. Let's try γ (gamma) Arietis, just above the thin Moon.

I was ready to star hop from β (beta) but I realised I had bull's eyed γ in the finder scope, the middle of the grouping of 3 stars, including ι (iota). I thought the double stars were identical, in colour and brightness. A yellowy white colour. They were easily split at low power, 52x [ed: that's 56x, not 52x]. I went up to higher power but their colour and brightness remained the same. They looked like a pair of little tiny car headlights. Or moth eyes! Have you ever seen moth eyes?! Exactly the same.

The seeing is not good. Airy disks were jumping around...

(It turns out that I've seen this double before. It is clearly marked in my Haas double stars book, checked off. It is also noted in my double star life list. Huh! But that check mark, for whatever reason, had not found it's way to my winter list. Honestly, I had a funny feeling about this... But, at the time, I couldn't put my finger on it. And I didn't bother to check my hard copy of the lift list... Oh well, it's still a fine winter double.)

Next up: ι (iota) Cassiopeiae. I star hopped from ε (epsilon). There is a little gaggle of stars near ε that served as a handy little arrow. Blinking, clearing my eye, at lowest power, I didn't see anything at first. Did I have the right star? I looked again... ah ha! To the right of the blue white star, I could see a much fainter dusty orange star. It was fairly close. I cranked up the power, first to 77x, and then 111x. Hey! It's a triple! There was another star closer to the main star, but below and to the left. It looked orangey too, same colour as the other nearby star. The closer star is slightly brighter than the more distant one. Very nice. Got out the Barlow and went to 222x. Now all the stars were easily split. A triple...

Oh, let's do a Position Angle notation, I thought! In order to make better log entries, I need to get comfortable with the PA. I shut off the drive for a moment to get the east-west bearing. Everything drifted to the left. This bearing was close to the line with the more distant star. North was up. In my mirror-reversed orientation, west was really west (like looking at a map). So I got that bit right.

Mentally I pictured an arc sweeping from the top, around the main star, down to the very close companion, counter-clockwise. So that put the A-B Position Angle at about 135°. And continuing around counter-clockwise, to the more distant star, the A-C PA was about 270°. I had no sense of the separation. I couldn't remember the size of the FOV for the 18mm eyepiece (which I assumed the 2x doubler would halve). Regardless, the AC separation was 3 times AB.

(I realised later in the evening, I messed up the orientation of the PA. My east-west, north-south was OK. But in a mirror-reversed orientation, the Position Angle for me will go in a clockwise direction. Right? So that would put AC at 90° and AB at 225°.)

And all this has made me wonder how the AB and AC and AD, etc, labelling goes. Are stars labelled by proximity or how they are encountered along the Position Angle arc?

So, on checking double stars for small telescopes, I saw that iota is described as a "grand triple." That it is. AB (the closest star) is noted having a PA of 230°. Uh huh. So the AB, AC is based on proximity (here, in this case). Then it showed the AC (distant star) at PA 115° (in 2004). Oh. That's different than what I noted... Close, in the correct general area. Has it moved? Or was my orientation off a little? Haas showed C is mag 9.0 while B was 6.9.

I was pleased. I was starting to figure out the whole PA thing...

The colours though. Haas says the main star is lemon yellow and the companion is blue. Webb and Smyth say: A is yellow, B is lilac, and C is blue. Man. Crazy.

That was fun, that triple star. I enjoyed that. Next!

I kept thinking about λ Orionis (and the faint star nearby that I cannot find on my charts). It was past the meridian. I wanted to get a good look while it was up high in the sky. And I wanted to have a good amount of time to do a detailed sketch. So at 8:57 PM, I headed back to λ Ori for another view. It was -8.7° and 54%. I pulled one of my custom sketching sheets, with the very large circle. I had remembered to bring out a clipboard. I attached my little red LED cliplight. Grabbed my B pencil and pink eraser. And tucked in.

I ended up plotting 14 stars.

Note: I had not drawn "G" on the sketch on my first examination. I added it later.

All right. I couldn't see anything else in the field of view. I glanced at the Oregon unit. It showed 10:22 PM. I hadn't realised at this point it was an hour ahead. I had set an alarm for the occultation on my palmtop to go off one hour before the event. I wondered why I hadn't heard anything at 10:13 PM... I was feeling a little chilled so I decided to take a break, warm up, and check my Psion.

There was ice on the mirror diagonal from my breathing.


The neighbours Lise and Don came out as I was finishing up my sketching. Awesome!

We shook hands, formerly meeting for the first time. I thanked them for turning off lights. They were keen to learn what I was doing. Lots of questions. The first was how much it cost. I let them have a look at the double star. I explained how I was trying to track down an uncharted star. We talked about the RASC. Then I turned to the Great Orion Nebula, M42. We enjoyed the grey nebula cloud surrounding the Trapezium. Don asked me how far away it was. I couldn't remember... I'll have to get that to him (1600 ly). Finally, I turned to the Moon. Lise was blown away by that! She said more than once that she never really looked up at the night sky. I gave them a RASC planisphere. Don was really interested in this stuff. I think Lise had a Galileo Moment.

I suggested they come out later, perhaps in a couple of hours, and we might get a look at Saturn. From the sidewalk, I showed them where Saturn was, below Leo.


Once inside, I quickly discovered I was way ahead of time! So, I decided to take the opportunity for a long break. Get really warm before sitting, in the cold, not moving, for up to an hour! I realised I need to wear another layer. I put my ski pants by the door...

In Stellarium, I reviewed lambda. My diagram was pretty good, surprisingly good positioning. I was seeing some stars down to 11.90 magnitude. But there was one star within the magnitude range, to the north, that I hadn't picked up.

So, around 10:00 PM I headed back out, encased in ski pants, to find this other star. And there it was. I hadn't noticed it before. It required averted vision to catch it. It was good to see it, to give as best a range of stellar magnitudes. I labelled this new star "G."

My candidate star "C" I noted was brighter than "G." That would then put C's magnitude higher than 11.70. I forgot to write down what it was less than! DOH!


I heard my palmtop alarm inside the house. It was 10:13 PM. Occultation time! 1 hour to go. OK. Grabbed, from inside the house, the shortwave radio for time signals and Samsung yepp digital music player for digital recording. Set them up near the garage. Couldn't get a signal from the Canadian channels; I picked up a medium quality signal on 2500.

Then, using my custom finding charts from Stellarium, colours inverted thanks to old Fireworks, I began to home in on the target star.

Just then Don came out to see what I was up to. Unfortunately, I was in the thick of it. I was not real good company at this point. I kept getting lost. He apologised for being distracting. I felt bad. I told him I'd keep him in the loop during my future observing sessions. He went back inside. I tried again from finder scope, 36mm, 26mm, and finally found the faint target star, and centred on it in the 18mm. The target star was GSC 02423-01036, a magnitude 10.1 star in Auriga, 3 degrees, 40 minutes due south of θ (theta) Aurigae.

It was about 20 minutes before the occultation prediction time of 23:13:00. I verified the recording was working OK. The radio signal was fading. I switched to 5000 kHz and it was much better!

I settled in at the eyepiece and dug the toasty hand warmer out of my pocket...

Not a lot to report here... For 45 minutes, I waited. The target star did not wink out. It did not waver in brightness. The only thing that happened is that my toes got cold. I had forgotten to double up on socks!

I wondered if Guy, up at The Forks of the Credit, had seen anything.

I packed up the occultation gear at about 11:45 PM. I was a little worried that the yepp had stopped recording. The display wasn't blinking! It did respond correctly though as I shut it down.


OK. What now? It was 12:01 AM (really). It was -10.3° and 56%. I checked the OneWorld weather station: air pressure was 1023 mBar. There was frost on the telescope case and some of my books. Saturn was still not clear of the house.

I scanned visually, with the finder scope, and with my binoculars, but I didn't see Lulin. Kept bumping into the Beehive.

More double stars then? Sure. Off to ζ (zeta) Cancri. I made the short star hop from M44 via θ Cnc. It was pleasing at low power. The primary star was pale yellow; the companion was very similar in colour. Perhaps a hint of orange.

Admittedly, going into this, I knew there was something interesting about ζ. It is listed twice on the Sky & Tel list. So that suggested it is a triple. But I wasn't seeing anything obvious. Was it the main star? The main star didn't seem entirely round. My imagination? I bumped up the power. All the way to 222x with the barlow. A figure-8, an hourglass shape, perhaps? I think I was just splitting the main star. Again, was it my imagination? I pulled out the 4mm eyepiece. 500x! Whoa baby! That didn't really help matters. The crappy seeing, the light pollution, I couldn't tell.

All that said, I'm pretty sure that I was seeing two equally bright, identically coloured points almost perfectly in-line with the more distant companion. The Position Angles should be similar. Those two points in the main star though? Incredible close.

Haas says: the AC pair is split at low power and are 5.9" apart. But the AB pair is 0.9 to 1.2" apart. I've split down to 1.5 (in fact, that was 57 Cnc). I've split Porrima (listed as 0.4" in 2004). Magnitudes between 5.1 and 6.3. And the PAs are 61 and 72°.

This will merit another look under better, darker, cleaner skies. Perhaps more horsepower will be needed...


I was feeling tired, lethargic. I was tempted to pack it up. But I saw now, if I swung the mount around the meridian dead zone, I'd be able to tag Saturn. Giddy-up!

At 12:34 AM, I could see a few moons.

Brian came out at that point. Or perhaps he had just returned from a midnight snack run. "You've been out here a long time." I hadn't really thought about it but, yeah, about 5 hours... I thanked him for turning off lights. We looked at Saturn, at 56x [ed: corrected]. He could spot the faint moons as I pointed them out. I explained why the rings looked the way they did, and why we could see moons, and how in general you knew moons from stars.

He asked some interesting questions:

"What's this?" looking at the whole thing. I wasn't quite sure what he meant. Really? The whole thing? "A telescope?" I answered. "Yeah, that's it." And I knew where he was going with it. "I couldn't remember if it was a microscope or a telescope." I pointed out, "They're essentially the same. It's just a question of which end you look in."

And, as per usual, "How far away is that?" And this time, I remembered. "Saturn is 1.3 billion kilometres away."

Cold, he headed inside. I dropped in a more powerful eyepiece and picked up another moon. Mirror-reversed, left to right, I saw Titan (4 to 5 total ring widths away), Rhea (1 rw), Saturn, Tethys, and Dione (both about 1/2 rw).

But I too was thinking of being inside. I packed up at 12:40.

That was a good night.


I got an idea for the OS weather station. I shouldn't place it in the triangle tray within the tripod. Space is at a premium there and it is easily toppled over. I'll fasten it to one of the tripod legs. I'll just need a strap of some kind around the leg.


I realised during the occultation, as the signal faded in and out, that you really need to keep the shortwave radio within arm's reach. If the signal was completely lost, you'd need to select a new station.

That also will require being able to operate the radio "blind..." Oh. That's gonna take some practice.


Another surprise during this occultation was that my seat position became increasingly uncomfortable as it carried on. This was because I had my adjustable seat set too low. I had not considered an observing session of 45 minutes. The telescope would move almost 15 degrees.

Also, I continue to find the seat angled slightly down. I should shim it again. Or put something grippy on the seat proper.


Another occultation note. I totally forgot to have a stopwatch with me, in case the radio and recorder failed. I'll have to make sure that's on my packing and pre-flight check lists.

No comments: