Monday, March 18, 2019

shot STF 1682 (Halifax)

Aiming at GSC 05538 00035, I asked the Burke-Gaffney Observatory to shoot the colourful multi-star system Struve 1682. Haas uses intriguing terms when referring to this star in the constellation of Virgo.

multi-star system STF 1682 in luminance

Luminance only, 1 seconds sub, a dozen stacked shots. FITS Liberator, Paint.NET. North is up; east is left.

aka HR 4877. The B partner, about 3 magnitudes dimmer, is close and to the west-north-west. The C consort is much dimmer, about 6 times the distance, lies to the south-west.

In double stars for small telescopes, Haas describes the primary as "pearly" and the companion as "ghostly" and "ethereal." She quotes Smyth on this one who says they are "topaz yellow" and "lucid purple." SkyTools 3 Pro shows the main stars as deep orange with a classification of K0 while the other two appear white. And B, aka SAO 157549, is a G0 star. It will be interesting to process the captured data in colour...

There's a fuzzy star along the centre left edge of the image: that's the core of the elliptical galaxy NGC 4742.

Sunday, March 17, 2019

monthly doubles for Mar 2019

Issued my double star "bulletin" for March 2019. It is a short list of suggested targets. I shared this on the RASC Toronto Centre forums. And I post here for all.

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Hello.

Days are getting longer and sun is getting higher. Hopefully weather more conducive to astronomy is around the corner. If you get chance to do some quick backyard observing, here are some double stars for your consideration.

staralso known asalternate catalogue(s)
HD 75646 CncSTT A 96SAO 80467, HIP 43535
α (alpha) LynSTT 571SAO 61414, HIP 45860
HD 60997 PupΣ1121SAO 153142
Struve 1126 CMiHR 2950SAO 115773
ε (epsilon) Mon8 Mon and STF 900SAO 113810, HIP 30419

A couple of hints... α Lyn is great triple as is HD 75646. STF 1126 is also a triple but the AB is rather challenging. HD 60997 comes with a couple of surprises!

I look forward to hearing how you did! Let me know if you have any questions.

Blake Nancarrow
astronomy at computer-ease dot com

Thursday, March 14, 2019

darkness again (Bradford)

It was dark again, with the shift in time. Stoopid system.

I could only see Jupiter on the walk to the train station. Clouds blocked Saturn. Venus was nowhere to be seen.

Monday, March 11, 2019

Binary Universe: more than just a clock

Saw a Facebook post which meant the April 2019 edition of the RASC Journal was out.

cover of the Apr 2019 edition of the Journal
Adrian made the Journal, page 2, with a fantastic hydrogen-alpha image. There's a lengthy article on radio astronomy at Queen's University, with a reference to the ARO, that looks very interesting. This ties in nicely with Erik Rosolowsky's piece on Fast Radio Bursts. John Percy has an intriguing article on pseudoastronomy that I will devour.

In my Binary Universe column, I return to the Android app Astro Clock Widget. I briefly mentioned in a past article when discussing apps that show sidereal time. But I wanted to share Astro Clock's many other interesting features including rise and set times for all the planets, the Sun, and the Moon, mini-display of the sky, and alerts of course.

Wednesday, March 06, 2019

spotted bright planets (Bradford)

During my walk to the train station, I saw Jupiter nearly due south and a bright but yellow Venus low. I wondered where quick Mercury was...

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Remembered that the Astro Clock Widget app on my phone would help. Learned later than Saturn was between them. Dang!

Wednesday, February 27, 2019

red band, white disk (Bradford)

Saw an evocative orange-red stripe to the east, at least from high ground. Couldn't see it as I neared the train station. A "sailor's warning..."

Noted a very soft crescent glowing in the south.

Snow is coming...

Tuesday, February 26, 2019

tomorrow's meeting cancelled

I just learned that tomorrow's Recreational Astronomy Meeting for the RASC Toronto Centre is cancelled.

cancelled meeting note from RASC Toronto web site

This is because of the impending heavy snow.

Monday, February 18, 2019

monthly doubles for Feb 2019

Issued my double star "bulletin" for February 2019. It is a short list of suggested targets. I shared this on the RASC Toronto Centre forums. And I post here for all.

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Hi there, hi.

If it isn’t cloudy and grey, it is bitterly cloud, it seems. Such that it is, here are some double and multi-star targets for your consideration for February.

staralso known asalternate catalogue 
φ (phi) AurBUP 79SAO 58051
11-12 Cam-SAO 25001
HR 2879 GemSTF (Struve) 1108SAO 79489
ζ (zeta) GemMekbuda or SHJ 77SAO 79031
HD 34071 LepGAL 378SAO 150258

Remember double stars work in the city as well as in dark skies. I look forward to hearing how you did! Any questions?

Blake Nancarrow
astronomy at computer-ease dot com

tested LED dimmer again

Tried LED dimmer again, with my little custom Telrad heater with resistors. Heat came out! Whiskey tango foxtrot, I thought this thing didn't work?! Carefully measured the amperage with the (repaired) Micronta multi-meter: 0.11A. Huh.

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Tried the other heat sources...

Big heating pad: 1.6A.
Kendrick 8" heating strap: 1.0A.
Hacked Heatech cup warmer: 700 mA.

Look at that.

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Tested the Kendrick 2" strap with the Micronta audible continuity resistance setting... and was able to get a tone when I bent the strap a particularly way. It has a broken wire!

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I don't know what happened... I don't remember now. But it seems that in late-January I was doing lots of little tests and checks and I had a malfunctioning multi-meter as well as an erratic dew strap. Looking back, the cheapo LED dimmer had worked fine.

My theory is that the dew strap itself was not working (hadn't been since early January) and it didn't draw any power from the dimmer circuit so I assumed the LED dimmer was bad.

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I need to make some good dew straps. I have lots of nichrome wire...

Sunday, February 17, 2019

finished dew controller

Buttoned up the dew heater controller. It works well. Now I can battle sultry nights on two independent rigs.

Cut the lead wires from the components off the bottom of the finished printed circuit board. Cut the test power feed. Used thermal paste between the sinks and the big transistors. Finally drilled the PCB for the large wire of the reverse polarity Schottky diode and connected the positive power input line.

Tried some plastic standoffs with tiny screws with hot glue but I wasn't really happy. Hacked some shrink wrap tube cut very short and used contact cement.

Wired up the fused Cigarette Lighter Adapter with heavy wire, cut a bit longer than my Kendrick controller.

Attached the case parts. Stoopid skating drill bits; should have used a press. Installed the Richlok plastic strain relief. Soldered the big pots and the indicator LEDs. Pressed the LEDs into place; locked. Soldered the shell tabs of the RCA female connectors in advance. Tightened the RCA jacks with a 9mm spanner. Once the PCB was glued in place, I soldered the RCA plugs on their centre pins.

Glued the power switch into the case. I wanted to use removable connectors to the tabs but they were too deep so I (carefully) hard-wired the SPST.

Summit Brand. Sony guts.

Heated the shrink tube on the power feed. Closed up the box. All done. Tested. Works good.

Project box sealed.

In a moment of inspiration, printed up some labels.

Shared the photo with Charles on Facebook. He quickly responded: "When we're observing and it's hit the dew point and our dew controller is already on ten and we need a bit more to get us over the edge we can go to eleven." Couldn't have said it better.

None more black.

Friday, February 15, 2019

gazing from 9700 metres (Lachute)

As we rose above the clouds, I noted the Moon, getting bright, high up. Couldn't view it straight on until the plane banked right.

Saw Sirius. Bright, blue-white, intense.

Then I saw deep orange Betelgeuse, and when I squinted, without my eyeglasses on, all of Orion.

Very dark sky above the pale blue clouds below.