Wednesday, December 15, 2021

grim day

Darkness abounds.

Wednesday, November 24, 2021

in the end

To my loyal readers... I'm still around. "Not dead yet." To quote Monty Python. But I'm still shell-shocked by what happened to me on October 16...


Today was pivotal.

I sent a formal letter to the RASC Toronto Centre. We'll see what happens...

My blood pressure is high.

My doctor is concerned.

Clearly, I need to chill.

Astronomy is good. In many ways. And under normal circumstances it makes me calm. That's a feeling I often experience when I look at things through the telescope: calm. Extreme, deep calm. 

The Universe slowly churning away, spinning, evolving, and letting us have a look around. Developing our theories and insights and rules.

I will endeavour to find some time under the stars. That's what matters. That said, it's hard this time of year. But I continue to closely watch the Clear Sky Charts...

In the end, there's no reason to be mean or vindictive or hold a grudge. But some hold grudges. They MUST win. No matter what. But they don't get it. Funny/odd when astronomers don't understand that. There's NO, zero, point in fighting. 'Cause you're gonna die, sooner or later.

Friday, October 15, 2021

avoid these terms!

I really like the and regularly visit for solar activity updates, sunspot identification, and interesting photographs.

But on skimming today's article on curious comet 29P/Schwassmann-Wachmann, I grew a little anxious. I hope this does not spurn other media outlets with phrases like "giant space volcano" headed towards Earth or comet in "superoutburst" ligthing up the whole sky.

Oh oh...

Tuesday, October 12, 2021

Stellarium webinar tomorrow

Free Stellarium webinar tomorrow! For anyone interested in the computer-based Stellarium product. 25 hours to go!

Monday, October 11, 2021

registered a gaggle

RASC Weekly included a mention of the Stellarium webinar. Signed up another 19 people today.

still can't edit

While John G found he could work on the Toronto Centre web site, I still cannot edit the national pages. This an authentication problem.

reviewed a .STX file

Received Melody's first SkyTools observing list plan .STX file. Reviewed the entries and gave some suggestions for the tricky ones. Good progress. She's gonna have another go. That I did a big of digging to find planetary nebula Jones 1...

Sunday, October 10, 2021

still locked out

Still can't get into the RASC national web site, cannot edit my Obs Comm pages. I got saw some issues and then finally got kicked out on the evening of the 6th. This crippled other editors.

locked out of the RASC web site

And the problem is cascading into centres. In Toronto, we cannot edit our site nor perform other member services. What a... mess. Absolute mess.

cut a circle

Finally cut a Teflon pad for the big Dobsonian I'm repairing. Used one of my hole saw bits, without the pilot, in the drill press, to cut a small circle. The 1-1/8" (28mm) bit. It's a tad smaller than the original but close enough (from an airplane). The issue is that these saw bits are measured by their outer diameter; the next size up, 1-1/4" (32mm), would make a circle too large. With a box cutter, I chamferred the top edge. Next steps: sand with course grit the bottoms of all and re-glue into the Dob ground plate... Dizzard! I'm all out of epoxy.

Friday, October 08, 2021

free webinar on Stellarium Oct 13

I have scheduled a free online webinar for the Stellarium desktop software for Wednesday 13 October at 8:00 PM Eastern Daylight Time. Open to all.

See the information page on the Toronto Centre web site.

This is a webinar aimed at people interested in the Stellarium software, either completely new to the software, or with some limited exposure. I.e. beginners.

The Zoom webinar size is limited to 100 people.

Send a message to stellarium AT rascto DOT ca if you'd like to attend.

Thursday, October 07, 2021

had a quick look at Stellarium

Started poking around the newest version of Stellarium, 0.21.2.

Saw what Chris saw: the Bookmarks feature is re-jigged. Or rather, bookmarks are gone. Now there is the "Observing List" feature...

There's something different about the location settings, I think, maybe? Subtle labelling.

Overall, looks similar.

used the smartphone

Did a review of making a custom landscape for Stellarium. I wanted to prove the process that a panoramic image from a phone or tablet could be turned into a background texture in the software. I expected it to work but I had never done it. In fact, I jumped up in the middle of the afternoon, popped out back, and shot a panorama with the motorola e6 smartphone and built-in camera app. Perfect uniform grey sky for the task at hand.

The image looked good when done and was an odd dimension of course, 9400 pixels by 1700 pixels, approximately. It took me a few tries but I got it work. With GIMP, I produced a 4096x2048 PNG with transparency. Hacked the INI file. It all worked. 

So a good review in the end as I had forgotten a few of the particulars. Touched up my notes in the Advanced Stellarium Quick Reference Card. Prepped sample files for training. Proof of concept met. And I'm better prepared now for my upcoming level 3 training rehearsal with the Stellarium team!

no activity for the second day in a row

No progress. I sent the Executive Director a list of open items from the Observing Committee many of which require support from the national office. Over 20 items. And some of them are big. And they did not fix the web site access problem either...

the focuser is ready

Sent Alister a quick update. The new focuser 3D design was complete with better inner threads and a bevelled/chamferred edge on the tube. Did some quick checks in Cura too. Exciting. It is ready for a test print!

Wednesday, October 06, 2021

wasn't me!

Learned that other editors are having trouble with the RASC national web site. I was applying my final edits and I got booted. I thought it was because I had triggered a too-many-too-rapid-too-many-uploads flag. Sounds like I didn't break it... At least I was able to update to the new general certificate application form.

Ooooh. Maybe that accounts for the radio silence today...

asked if we can hide it

Pinged our webmaster to find out if we might have an orphaned page on our site that will not be visible to the crawlers...

no stars (Bradford)

Curbed the recycling. Cloudy! I need to check HR 6043.

coached on list-making

Did some over-the-phone coaching for Melody. Showed her how to make a list in SkyTools 4 Visual. She's gonna have a crack at the Deep-Sky Challenges program!

reviewed a viddie

Reviewed a short RASC TC RAN video before release.

no replies

The list grows. The requests are piling up. I thought I'd hear from the staff at RASC national office today. I think I have 10 open pending queries with them. And at EOB, nothing. No replies, no call backs, nothing. Sheesh.

lots of paper in an office

There are a lot of members in the lurch here... it's not just me.

skimmed SkyNews

Looked quickly at the new SkyNews in bed before fading. I look forward to reading the article on the James Webb Space Telescope. No article from Yours Truly in this issue.

redid the tube

It worked!

After a lot of tests and trials of OpenSCAD and MeshMixer, I had a rethink. I believe it was during my catch-up chat with Ward, while trying to demystify meshes and solids, that I decided to redo Alister's focuser tube from scratch in TinkerCAD.

Not trivial. Took me some time, some YouTube videos and 3D design tutorial pages, to learn The "Tinker" Way of doing things.

Celestron First Scope focuser tube from TinkerCAD

This is version 1. Overall it's good but I want to redo the tube.

The inner threads don't look deep enough. I need to make the cutter 1 mm bigger I think. 

Also the edges of the tube are not chamferred. I didn't think this possible in the new tool but I learned today how to do it. 

Tuesday, October 05, 2021

the last SkyNews of 2021

[ed. I did not post at the time of arrival that I received the Nov/Dec issue of SkyNews.]

cover of the Nov-Dec 2021 SkyNews
Chris Vaughan reviewed the latest edition of The Backyard Astronomer's Guide (TBAG). One of my favourite books and (I believe) instrumental in my getting seriously into the hobby.

Eric Klaszus shared his meteor hunting adventure. 

Nicole Mortillaro discussed cold weather observing.

And Dan Falk wrote about the new James Webb Space Telescope.

Oh yes. And many geek out on what they'd like Santa to put under the tree or in the stocking...

Once again I am liking the new cover design.

See the snippets online.

made some lists for motors

I finally got 'round to making some motor maintenance lists as well as the parts-supplies-tools list for the impending CAO mini-work party. I'm on duty for winterising the mowers and changing the oil for the generator.

Ah, ah, winter! No no no no.

Need to double check if we have all the supplies on site.

a special meeting

Attended the special council meeting of the RASC Toronto Centre on the matter of land acknowledgements.

a gap

Reminder (late) arrived in the electronic inbox. Journal submissions due.

I declined.

I wrote 41 articles for the RASC Journal starting for the February 2015 issue. Consecutive. This will be the first gap.


Sent the mount-control notice for the next Stellarium level 2 gig.

Monday, October 04, 2021

getting consensus

More soft votes coming in... I put out a simplified proposed 2022 budget for the Obs Comm to accommodate for more pins, including a new set, and more sheets. Looks like everyone is OK with what I'm suggesting. I snuck a "absolutely no brown ones" line into version 1 of the proposal but no one caught it. Oh well.

off the hook

Yesterday Paul M asked if I might deliver the Sky This Month presentation for RASC Toronto Centre for November. Ugh. I don't know if I enough cycles. There are other factors too. It gave me pause. But then he pinged me today. He found another presenter willing to take it on. Good!

invited to speak at Sarnia

Was invited by the Sarnia centre to deliver a presentation on the RASC observing programs. They asked about October but I had a conflict! So we pushed to the Monday 15 November meeting.

hacked the code

Did I speak too soon? OpenSCAD is not without issues. It seems the Customizer form fields, if they were not initialised with a decimal number, will not accept a decimal number. So I truly had to hack the code a bit... Trying to get the bolt diameter to be 35.5 mm.

Sunday, October 03, 2021

copied the bolt code

Holy Universe!

It worked.

I copied the code available from the Thingiverse Nut Job Customizer and dropped it into OpenSCAD.

nut job code in OpenSCAD

Woo hoo! The Customizer populated and then the bolt appeared. Yes! No errors. It's... it's incredible. 639 lines of C-like code.

Sidebar: I'll be able to make other fasteners for 3D printing with this tool... Or hack the code of my 3D models... Interesting (said in my best Mr Burns voice).

This is brilliant. I need to generate a very large bolt pattern with a 1mm thread pitch for Alister's focuser tube and the Customizer inside Thingiverse is broken. 

It seems many things are broken in Thingiverse...

Now that I have OpenSCAD 64-bit on the Windows laptop, I'll be able to make the part to import into my 123D project.

Well. I'll be able to do that when STUPID WINDOWS 10 stops thrashing the hard drive!


Guess I'll do this in a few hours... stupid stupid stupid!

Hey, Microsoft. Your operating system IS a virus.

worked the numbers

Worked some of the count and budget numbers for the national Observing Committee. Discovered some cautionary situations. Predicted inventory numbers for the next year or two. Shared with the team. Heh heh...

learned how it went

Debriefed with Chris, Denis, and Ralph after the Dunlap Institute planet party webcasting from the Carr. Lots of good info.


YouTube video now online. Total run time is 2½ hours. Michael Reid starts around 5½ minutes in.

pitched more peeps

Pitched some more people for the intermediate Stellarium course on 18 October. Was very careful with the dates and times on this message... after the cacophonous confusing deluge from last week!

viewed the new config

Read the article over at SpaceFlightNow on the orbital outpost. It's titled, Cosmonaut shares new perspective of International Space Station.

Great shots show the new configuration of the canted Redwire solar panels plus the recently-added Russian Nauka lab module.

the ISS as of autumn 2021

The photographs were captured by Pyotr Dubrov from his Soyuz before returning to Earth.

The excellent shots show the exterior of the ISS from a few hundred metres. Been a while since we've seen some good beauty shots. There are two SpaceX Dragon spaceships and a Northrop Grumman Cygnus supply craft docked. I particularly enjoyed the view of the lab’s new roll-out solar arrays.

Saturday, October 02, 2021

learned the parts separated

Yesterday, I received an email from Alister! 

I was starting to wonder what had happened. Hadn't heard from him for a while about his Celestron First Scope focuser tube issue. 

Had he dropped off the edge of the Flat Earth...?! Did he not care any more? Had he thrown the whole telescope in a big round bin? Had he found someone nearby to help? Had he bought the replacement part from Celestron? Ha ha ha ha ha ha ha ha ha ha ha ha... oh... ha ha. That was a good one!

I was rather pleased to hear from him. He shared that he had finally discovered the misplaced parts. Two different boxes, he said. He included some measures.

The best news was made abundantly clear in the attached photo.

Celestron First Scope focuser tube parts

The focuser tube was a two-part item! Yes! 

I immediately took mine apart. Easy. Look at that!

A whole bunch of problems went away, dissolved with this photo. The tube part proper, it's construction in a 3D model tool, now got a lot easier. Alister would not have to drill and tap a collar piece. That he found his meant I didn't have to do anxiety-inducing exploratory surgery on mine (although it probably would have been moot).

Measured the outer diameter of the threaded part of the collar with my trusty ole' micrometer, twice: 35.5 mm. Double-checked the inner diameter of the tube: 35.0 mm.

I could now finish the 3D design... Onward and upwards.

check out all our events

Be sure to check out the RASC Toronto Centre web site for all the events we're doing in October!

checked a double sketch

Mr Chapman shared a double star sketch from his little log notepad. I used my checker and in 15 seconds I knew he was on target! He was happy to hear that. Love it!


Heard from a long-lost member of the Observing Committee. Wow! Very good to connect.

the good, the bad...

Out of the blue... A member used my apology email to reach out. There was some good news and some bad news.

The good: her Explore the Moon certificate and pin had arrived, at last, after 69 days! Whew.

But then she said, "Any chance of me getting a certificate with correct spelling of my name."

Oh my Universe.

After all that!

It is still not right, 69 days in...

Kinda kicked the pegs out from under me.

Friday, October 01, 2021

made new app forms

I built new application certification forms in Microsoft Word, for the Explore the Universe and the generic app for all the other RASC observing certificate programs. The originals were lost years ago. Not having Adobe Acrobat, I hunted around for a cheap or free PDF editor tool. Found PDFescape. Easy, light-weight, fast. Just what I needed. I converted the PDF exported from Word to a fill-in form. Circulated the drafts to the Observing Committee for review. The prime reason is to switch from the previous chairperson's home address for mailing apps and logs... 


Here we go again. RASC events happening on the same date. Dividing, conflicting, and upsetting our resources. I myself am caught in the middle. I could go to the the CAO to operate telescope camera equipment there. I'm a super. I have the keys. I know what to do. Or do I stay in the GTA? I am one of the few trained operators of the 74-inch telescope. And I have some experience running a camera on it.

T intersection sign

I truly don't know which way to go. There are only a few people who can do, or are willing, this.

reviewed the by-laws

Read the RASC Toronto Centre by-laws. Was looking at how members need to be notified of the Annual Meeting. And what information needs to be provided.

relayed the EPO call

And I shared the volunteer ask for an event at the end of the month, with the Ontario Science Centre. The chair of the Toronto's Education and Public Outreach did not post this himself directly on the forum.

relayed DDO ask

Shared the volunteer ask for the October events planned at the David Dunlap Observatory. The DDO chair still can't get do this, still can't get access to the Toronto Centre forum, to share updates and news. Account issue, related to the new database. Ongoing glitches. I've asked national office twice now to resolve this matter... It thwarts our DDO team's ability to rapidly convey messages.

Thursday, September 30, 2021

used the new checkers

With the Double Star checker documents at the ready, I scanned the sketches submitted with a Double Stars certification application. Handy! Comparing was quick and fast!

made another checker

Made another checker, once again, using SkyTools 4 Visual Pro. This one for a rotated view, perhaps presented by a Newtonian telescope (or a refractor straight-through!). Used the other version as a template. So, hopefully this and the mirror-reversed version, will ease and speed the checking of the submitted Double Stars certificate applications.

that ends well

Appeased a youth and his family. We look forward to receiving a new keen youth member into the RASC community.

Wednesday, September 29, 2021

noted clouds (Bradford)

While curbing the bins for the next morning pick up, I noted the sky. Not pristine. The spotty clouds were probably thwarting efforts by some RASC members at Glen Major Forest. Too bad. Tagged Jupiter over the roof of the house as I walked back from the street. Pretty for west actually, perhaps west-south-west by the compass.

showed how to use the web interface

Helped an ObsComm member with accessing the forum/listserv via a web browser on a computer. Looks like they are not getting emails delivered to their tablet for every forum post. This will let them compare and if we need to, collect forensic data.

trained new staffer

Met one of the new RASC office staff, along with the exiting membership coordinator, and the Exec Dir. I was able to offer some "training" of the certification handling process, supported by my swim-lane flowchart. I think this will streamline matters for the Observing Committee volunteer and the Toronto office staff.

updated the checker

Updated the Double Stars certificate checking document. It now features the target pair description from the Supplement along with the individual magnitude values. It also shows the B-V values!

page from the Double Stars checker doc

This completes the work on Mirrored version. Now onto the Rotated one...

Tuesday, September 28, 2021

attended a planning meeting

Attended a planning meeting for the SCOPE newsletter. Odd. The organiser did not actually book anything in a virtual meeting tool. Assuming. Which then made for a late start! And the new editor did not show up. Broken.

another council meeting

RASC Toronto centre members have been invited to another council meeting, this time to review the matter of land acknowledgements in our future meetings and events. RASC national representatives will be on hand. The official notification PDF file sent out had typos in it. Can't even get that right. But I believe it is on Tuesday 5 October at 7:00 PM.

met with E.D.

Had a good chat with the Executive Director. Did a bunch of post-mortem and ideation for the future. Hopefully we will have the observing certificates... issues... sorted very soon.

Monday, September 27, 2021

reviewed a draft

Reviewed a draft of a new RASC observing program. This will be neat!

sent apologies

Issued over 15 apologies to observers who have not received their RASC observing certificates.

asked to be removed

Asked to be taken off Sissy Haas's mailing list. I can't take it anymore.

CAO information to review

Received matters for the planning of the fall maintenance at the Carr Astronomical Observatory. 'Cause I care. Also received some pixel-y HUGE images. Oh my.

notified of council meeting

RASC Toronto Centre councillor Ed T sent a message on the forum informing members of Council's next meeting. Council will meet Thursday, October 14, at 7:30 PM, virtually via Zoom.

Sunday, September 26, 2021

switched pants

Ooh. I ate too much at birthday dinner. So, once home, I switched to my new George Men's Jersey Pajama Pant with stars and constellations. Gift from Rhonda.

comfy pants with stars and constellations


put on socks

Headed out to dinner. So, of course, I had to try out a new pair of NASA socks by Mad Engine. Chose the grey-black pair out of the three pack. Orbit Day gift from Rhonda.

did some training planning

Did a bunch of Stellarium training course planning. Arranged for introductory courses to be taught by the other trainers. I'll deliver an intermediate in October. And I circled a date to run the webinar/Q&A session. Been almost a year. Oh, and suggested some dates for the level 3 advanced rehearsal test run...

Saturday, September 25, 2021

we got lucky

Looks like the Sun's gone out and it's raining again. We got lucky last night at the DDO, this thin sliver of clear skies at night. I'm going to listen to the sky-water falling down...

late checkout from DDO (Richmond Hill)

Helped at the Up In The Sky event from the David Dunlap Observatory... yesterday? Yesterday.

I headed down in the late afternoon so to have a good amount of time to set up and prep, feeling a little rusty, and wanting to work on my own. Quite cloudy during the trip down. Maybe this wasn't going to work...

Then some slack time.

When Denise arrived, I had the dome open, cooling fan running, Stellarium running, adapters out, Visitor eyepiece ready, finder MallinCam going, my laptop John Gomez going, my new USB headset at the ready, sidereal time set, upper door open (after some persuasion).

Received Andrew's MallinCam Universe.

The skies were perfectly clear!

Targeted Saturn quickly but the camera image was breaking up. As I tried to sort things on my work, I was awarded a BSOD for my efforts. With about 30 minutes to go. Stress I didn't need. While I waited I fired up the DDO ASUS laptop but neither Denise or I could remember how to log into it.

Finally Win 10 came back and all was well. Received the VDO Ninja information from director Andrew. And suddenly I was on, talking about Saturn, the second largest gas giant in our solar system.

Rick and Claudio and Ron took turns talking through the evening. 

After Saturn I headed to Albireo. When I sat down and put my headphones on, they were transitioning to me. Yikes. Wasn't ready for that. So I quickly found my notes and talked about double stars.

Then I went to Jupiter with the 23 ton telescope. And was ready when they tossed the football to me.

Took an audience question.

And then I was done. There was some talk about me doing another target, beyond what was scripted, but I suggested others should show things. Even Ward was able to share an image, his comet C/2020 F3 (NEOWISE) shot from the summer of 2020.

Jupiter through 74 via MallinCam

This gave me time to work on the DDO portable computer. Got logged in. And discovered the MallinCam Universe software had never been installed. So I did a near-field Bluetooth transfer of the control app and the driver. Swapped out my computer for the RASC unit and connected successfully to the camera.

I tried viewing τ (tau) Cygni.

When the show wound down, the lads from the lawn came up to celebrate and do some quick training and refreshing on the 74-inch.

Claudio in particular wanted to try his cameras. We spent a lot of time experimenting.

During this, I tried to improve the focus of the finder scope with its MallinCam. That worked, the Ring Nebula obviously improved on the TV monitor. But as I locked down the focuser, the little refractor moved in the ring holders. I spent the rest of the evening trying to realign it. Frustrating. I still think its off so I'll have to revisit that...

Denise and I closed out the dome at 2:42 AM.

I gave her the my 3D model of the telescope printed by Steve. She was thrilled.

Seat of the pants, tonight. But Denise was happy. First time I went to three different targets in the same show!

Wow. Long night. Home after 3 AM.

Thursday, September 23, 2021

checked Teflon

Finally had look at the Teflon procured from a plastics co. in the GTA thanks to Tony. The stuff is heavy!

heavy plastic

Three pieces. The long rectangular is 3/8"; the two squarish pieces are 1/4".

  • 15-3/8 x 3-1/4
  • 7-3/8 x 4-3/8
  • 8 x 5-7/8

I can now finish my Dobsonian base build...

And fix the big Dob from the DDO.

to fly the 74

There's an Up In The Sky event planned for Friday evening. It's an online event at the David Dunlap Observatory. I'll be operating the 74-inch telescope with camera attached. If the skies clear, we'll show some live views of astronomical objects.

See the RASC Toronto Centre web page for more information.

There are still tickets availalbe at the Richmond Hill web site.

Sorry! Registration is closed.

Wednesday, September 22, 2021

plus 10k

Holy cows!

My barn door tracker YouTube video has over 10 000 views!

That is so wild.

not again!

The Toronto Centre president again said the CAO house could not be booked by members. Ralph and I tried to correct this messaging in the YouTube chat. Sheesh.

The upper level can be booked by one party.

the terrifying Universe

Enjoyed Dr. Leo Yvonne Alcorn's talk on Lovecraftian fiction with scientific content for the day.

She took my question. I asked if she had a Flying Spaghetti Monster bumper sticker on her car.

She didn't. But she wants one.

received October Journal notification

Member Services sent out the notification for the latest Journal of the Royal Astronomical Society of Canada. The October 2021 issue is out.
cover of the October '21 JRASC

Aurora on the cover. Aurora prediction software in my column.

Katrina discusses star culture in a colonised world. Dave C talks about seeing gegenschein in a peculiar spot. John acknowledges CASCA's 50th year. David L looks back on Carolyn Shoemaker's life.

My Binary Universe column is about one of the better aurora monitoring apps, Solar Monitor, for the iOS platform. Not perfect and a little pricey but helpful with an information-packed main screen and timely notifications.


The Journal or JRASC is available to the public. Download it now. Enjoy!

Monday, September 20, 2021

taught Stellarium intermediate

Delivered another Stellarium level 2 course. Good crowd. Good questions. My mount behaved just fine!

imaged STF 2146 faster (Halifax)

Shot double star HD 156162 aka STF 2146 aka SAO 30299 again! Faster still! Twice as fast as 12 days ago. Also switched to the SBIG camera. In Draco.

Struve 2146 in luminance

Luminance only, 0.1 seconds, 12 subexposures. FITS Liberator, GIMP.

Caught it in stunning conditions...

Well... I don't think AB is round.

This is the shortest value allowed with the BGO rig. So I cannot shoot any quicker. That's it.


WDS entry updated! There's no B. The tight companion is near C. See the 29 Aug '21 blog entry for details of the change.

Sunday, September 19, 2021

posted Sep '21 doubles list

Prepared my double star "bulletin." It is a short list of suggested targets. I shared this on the RASC Toronto Centre forum. I post here for all.


School's back in, sorta. Summer's over, sorta. One thing for sure: the Moon is back, big and bright. And that means you need to shift to planets, variables, and double stars.

Here's a short selection of doubles and multi-star systems from my life list, ones I find impressive and interesting.

staralso known asalternate catalogue(s)
β CapΣA52, Dabih, 9 CapSAO 163481, HIP 100345
ε EquΣ2737, 1 EquSAO 126428, HIP 103569
HD 177904 AqlΣ2449SAO 124265, HIP 93822
HD 203320S 786 CygSAO 33323, HIP 105298
V402 LacHJ 1735SAO 51698, HIP 109354

Have a go. See if you can split them and detect colour. I hope you'll share your discoveries.

Blake Nancarrow
astronomy at computer-ease dot com

Notable double star designations:
Σ = F. Struve, STF
ΣA = Struve Appendix I, STFA, Σ1, ΣI
β = Burnham, BU
HJ = John Herschel

learned of the second!

Wow. Heard of another RASC member completing the Double Stars program. A Toronto Centre member this time. Yes! So exciting!

Saturday, September 18, 2021

made a new calculator

Made a new, updated, hopefully easy-to-use online spreadsheet for Melody to use. It's basically fill-in-the-blanks and it should yield a good separation value for a double star.

It's pretty snazzy.

Onboard instructions and notes.

Constants sheet for the Earth's rotation rate and the sidereal time factor.

Supports variable Linear Scale divisions, say 50 or 60!

Prompts for a dozen drift times, taking the average.

Prompts for the star's declination, so to compute the speed of the sky.

With that, the Scale Constant can be determined (per my proper formula).

Supports four scale constants with and without magnifiers and reducers.

Finally, prompts for double star pairs and their separation in tick marks on the Linear Scale.

Computes the true separation or ρ, rho for a dozen pairs.

Hope they like it...

helped Bruce and Melody

Chatted with Melody and Bruce about their new Meade Astrometric eyepiece. Told them to not use Meade's faulty instructions. Explained that the speed of the sky was a factor. Demo'ed the process with my new spreadsheet. Readied to invite them to the shared file...

Friday, September 17, 2021

did some math

Another interesting journey...

I started a round of research to learn or verify how to measure double stars with the Meade Astrometric ocular with its illuminated reticule and its central Linear Scale with 50 divisions.

My experience is with the Celestron or baader planetarium Micro Guide (now discontinued) with 60 divisions. 

I had a bad feeling that my method and separation calculation would not work. I wanted to help Melody learn how to use hers but feared my technique would not apply.

"Let's start from scratch," I thought. 

Did some broad internet searches.

Landed in a Cloudy Nights thread started by Jeremy Perez no less. He was trying to learn his Meade Astrometric eyepiece. Perez developed his external protractor. People recommended Tom Teague's method and Bob Argyle's book. But in the end, it didn't reveal to me a formula.

Then I found a thread in the Stargazers Lounge. Davey T asked how to use his Meade (though he showed a reticule image for a Celestron) back in the spring of 2015. William aka Oddsocks gave a procedure referring to a star at zenith. A day later he backtracked. On reading Qualia's notes for a Micro Guide, he realised his instructions were wrong. But he had simply relayed the notes from Meade.

It is strange how you read something from a "respected" manufacturer and believe it must be correct...  I realised the published linear scale calibration method in the Meade document is garbage!

Oh my.

The Meade document is useful in other details but the linear scale calibration method can be ignored unless you are living on the equator

So I still did not have a formula.

But now I was getting more nervous for Melody's sake.

I read Qualia's blog post on measuring doubles and Jovian moons with the baader Micro Guide. Some pretty good notes.

Finally, I found a formula for calculating the drift’s scale constant.

S.C. = 15.0411 * T.avg * cos(Dec) / D


  • S.C. - Scale Constant
  • 15.0411 - Earth’s rotation rate per hour in degrees
  • T.avg - the given star’s mean average drift time
  • cos(Dec) - cosine of the star’s declination
  • D - number of division on the linear scale

I compared this to my formula:

ρ = D * T.avg * SidFact * cos(Dec) / 4


  • ρ - separation in arc-seconds, rho
  • D - divisions or ticks on the LS, in decimal form
  • T.avg - average drift time in seconds
  • SidFact - sidereal time factor or 1.0027379
  • cos(Dec) - declination of the star, in decimal form

Some marked differences that unnerved me. Oh boy.

Couldn't seem to find the source for my formula...

Still, there seemed to be something going on here. I could not see it at first... But after a lot of head-scratching and noodling and staring and some home-made spiced rum, I realised what it was.

The 15 (and change) value divided by 60 divisions gave 1/4 (close enough from an aeroplane). That was what I was using in my formula! Whew. They were essentially the same. That was a big relief. So I made a new universal formula considering everything.

S.C. = ( RotRate * T.avg * cos(Dec) * SidFact ) / D

And then you multiple that by the counted ticks on the scale to get ρ, of course.

I really like this new formula since it will work with any reticule regardless of the divisions and as it integrates the sidereal time factor too, which I also cross-checked.

That's produced by dividing 86400 (regular day in seconds) by 86164.0905 (a sidereal day in seconds).


Along the way I could not find an official PDF on the Meade site for the ocular. I could only find it on one of those suspicious manual sites...

But I finally saw it with my own eyes. Step 4: Aim the telescope at or very near (within +/- 5°) the zenith (perpendicular to the ground).

Later they said to take three timings. Ugh. More bad advice.

And there it was in writing, after the step-by-step procedure. Stars at or near the zenith move across the sky at 15 arc seconds per second (sidereal rate).

No. Wrong. Completely wrong.


Oddsocks had called it. The true separation formula provided, ( T.avg * 15 ) / 50, would only work for observers at the equator.

So, again, the formula I made should be used:

S.C. = ( RotRate * T.avg * cos(Dec) * SidFact ) / D

This tells you how much real sky is between the tick marks on the Linear Scale.

Sorry. More work. And some trig. Sorry! But you'll get rather accurate results. I tested it in Stellarium with the Meade reticule view.


In follow-up messages with Melody, I learned that the instructions in her eyepiece box were like the ones I had stumbled across. New eyepiece from a 2021 sale with old bad instructions. Wow. It's amazing to me is that after all these years Meade hasn't fixed it or issued new information. Terrible.

content for NOVA

Arnold B reached out. He's helping with the national NOVA revamp. Good news. He asked if I might help with some Stellarium content. Let's talk.

tried rho Ori in a small 'scope (Bradford)

Back inside after the brief back yard observing session.

The plan was to spot the B companion to ρ (rho) Orionis, while I had a clear patch. I was concerned the double, in the new observing certificate program, might be too difficult for an observer with a small instrument. 

But I saw it.

It was challenging to be sure in the Meade ETX 90mm.

But it was definitely there.

With the Tele Vue 9mm Nagler Type 6, it was well beyond first diffraction ring. It was even visible in the old Celestron Plössl 26mm eyepiece. Detectable. The best view was with the Pentax wide view 20mm ocular.


I spotted C too.

B was to the EEN or EEEN, opposite HD 287611, very tight, much dimmer.

I viewed this double a bit before the meridian. Star hopped from Bellatrix. 

Pleiades up high.

Winter is coming.

Tempting to continue but... I was too tired.

I thought rather good seeing, average trans. But damp. Very humid. The grass was wet.

Pulled the Clear Sky Chart. Cloud cover: clear; transparency: above average; seeing: excellent; Moon: -22°.

Clear Sky Chart for Friday morning

Pulled the weather data from EC. Current Conditions. 11°C. Observed at: Egbert. Date: 5:00 AM EDT Friday 17 September 2021. Condition: Not observed. Pressure: 102.2 kPa and falling. Temperature: 11.3°C. Dew point: 10.8°C. Humidity: 97%. Wind: ESE 4 km/h.

So, a good experiment. 

No modifications needed...

Wednesday, September 15, 2021

suggested peeps

Chatted with Tony on some Nom Comm candidates in the Toronto Centre. It's that time of year...

heard the reticule eyepiece arrived!

Melody shared with me that her Meade Astrometric eyepiece arrived.

That was quick! From the UK. 

Then she said, "Now to learn to use it!" Indeed, I encouraged her to watch my double stars measurement video... 

But then I had a sinking feeling! Would the formula in my video and companion notes work?! The Meade as 50 divisions in the Linear Scale while the Celestron/baader has 60. Oh oh. I had a feeling that would affect things. 

This kicked off a round of research...

Tuesday, September 14, 2021

heard of the successful test

Ask Jo if he could test our uploader service in the Linux environment. He tested in a light-weight browser on Zorin Linux. Said it worked like a charm and was fairly fast.

checked the alignment

Shared some stills and a video from SkyTools to Chris V for the shadow transit near—not directly atop unfortunately—the Great Red Spot. Not aligned.

shadow and spot according to SkyTools

Checked in SkyTools 3 (manual) and 4 (auto).

checked another vid

Reviewed another video for the RASC Toronto Centre A/V team.

shared a thin design

Stumbled across an image of a "thin" barn door tracker design. Forwarded it off to Ian B who is starting to build his own.

processed trainees

Did some Stellarium training processing in preparation for the level 2 gig on 20 September.

asked for a DDO account

Submitted a request to national to reimplement an account for the Dunlap Observatory chair. Without it, she cannot access the RASC Toronto services...

fielded a query about a Moon photo

Yet another query came in via the RASC national web site observing form.

This time the person felt that in a photograph of the Moon they captured a shadow cast from another planet. 


I offered to look at the photo.

Unfortunately it was a shakey, hand-held, zoomed out, out-of-focus, low resolution, overexposed shot from a smart phone and saved in JPG.

Just an artefact, I argued.

Keep trying.

the very first one

Received the first-ever fully-completed RASC Double Stars certificate application! This just made my month.

chatted with the chair

Chatted with chair of the David Dunlap Observatory. Dealt with a number of open items. Curious of the status of a camera. Curious if I was needed. Recommended some other contacts for receiving notifications, for better coverage.

Monday, September 13, 2021

rejected some members

Issued rejection notices. Half dozen. General members continue to get confused and try to join the operational committee RASC Obs Comm forum workgroup thing.

relayed the good news

Shared some happy news with the RASC national team.

Harry from Uganda had found his Explore the Universe certificate and pin.

Toronto to Uganda

In fact, it had arrived on 8 April but the mailman never informed him!

Another loop closed.

proofed column

James asked, on the 9th, to review my Journal column draft, and respond before the 13th.

But Chris had my latest images. In his iPhone. In Richmond Hill. And he was at the CAO over the weekend. So I nudged Chris early Monday morning... A tad late.

I noted the wrong image was used for Figure 3. Sent it again.

And I provided an updated image for Figure 1.

Finally, I reworded some text in the Bits and Bytes section to be past tense.

picked up Teflon

I diverted during the drive home. Picked up purchased Teflon pieces. Heavy!

Sunday, September 12, 2021

received more silica

More silica packs. Yes! My sister continues to put these aside for me. Thank you, thank you. Now. If anybody needs some...

Mask of Constellations

Received a little gift from sis.

An Ardene face mask.


With constellations! Cool!

reviewed her last observation

Melody shared another double star observing log page.

She said it took two early mornings to observe the B star... "very tiny, couldn’t see any colour..." Kept checking if she was on the right target.

I reviewed her notes and sketch for ρ (rho) Orionis, cross-checking in Stellarium on my Mom's Macintosh. Too bad SkySafari does not show it! Sheesh.

She got it!

At 40 degrees elevation, she viewed through 2 air masses. That said, the target at 45 degrees was about has high as it would ever get, for us.

The main issue with the dim companion star is that it is 4 magnitudes dimmer than A. So the primary star would overwhelm the view.

I also felt she tagged the C star in her sketch but pointed out it was the first one, not the second one, to the south-east.

It is a challenging target.

She made a remark about whether it would be visible in a small 'scope. I took that to heart. I only observation had been with a C14. I'd try with my 90mm later...

Her last required observation!


Checked the view in SkyTools.

rho Orionis as shown in SkyTools 4 Pro

All good.

Friday, September 10, 2021

in the line of fire?

No pun intended...

Received a query from a person from the general public via the Observing Committee web page form.

Subject: identify rock/metal fragment


The person said they had found a small fragment of burnt metal/rock in their backyard lying on top of the grass and assumed it to be space debris. They doubted it was a meteorite because it wa relatively light. It was very hard and she could not break it. She wondered if it was from the fireball seen on August 22 from Crystal Beach.

I responded. I declined an offered photo. I shared a link to the University of New Mexico web site, into the Geology department. Encouraged her to read the information there. I also told her that if it really is from space, she should immediately protect the object from contamination by bagging it. I also suggested taking it to the geological or geophysics department of a local university.

more IT support

Helped Chris some more with IT matters at the CAO. He rebooted the main router and lots of things started working better. Doesn't make sense but anyway. Then Backyard EOS wanted credentials so I shared those. It said it all worked. Most importantly, the network speed from the SLO was improved.

learned DSG history

On 7 September, Mike S filled out the contact form for the RASC national Observing Chair. He had a query about the Deep Sky Gems program.

Mike noted a change made to the list in the summer of 2020. The editor's note states that Levy 402 was introduced in place of Levy 226, however the numerical listing and detailed object tables both show Levy 226 present, and Levy 225 deleted. He did not see an update regarding this apparent conflict of information. He asked for some clarification.


I was pressed for time so I quickly acknowledged the receipt of his message. 

Today, I followed up with a detailed reply on his interesting observation.

I shared with Mike that in late-July and early-August, I started a dialogue, with the editor and content owner. I had concerns with the Deep Sky Gems list. It was when I personally considered pursuing the DSG program and did a deep dive that I started to see a number of issues.

In fact, on 1 August, I pointed out this very matter, 225 was missing, 226 remained. And curiously this specific question had never been answered! I did do not know what was intended but guessed it a simple transcription error. The editor meant to say that 225 was replaced by 402.

I thanked Mike for drawing attention to this matter in the Handbook. It needed to be reported and noted in errata documentation...

Then I went on. I told Mike I was anxious about list changes occurring every year or so and I had raised the matter with the Observing Committee. Others were not aware that this was happening. In particular, I wanted to know if it was affecting him. I was concerned that if he was working through the observing certificate that periodic changes might throw off the member.


Mike replied and shared his experiences with the DSG program.

Since first approved, a total of fourteen objects have been changed. That was an eye-opener.

He recommended that changes in the Observer's Handbook be reported by the Observing Committee when they report to National Council so there is an official record. And be included in a RASC Bulletin. I absolutely agree. He noted that if the OC is not being informed of changes being made, they should be. Yes.

These changes challenged him since 2010.

He also noted the original introduction stated there was only one object that overlapped with any other RASC lists. As he worked on the list he found three additional duplicates, one with FNGC and two with Deep Sky Challenge. These were reported and subsequently removed and replaced with four new objects in the 2013 OH. Eight of the fourteen changes mentioned above.

carpet yanked

He agreed with my comment that an observer could be thrown off if changes are not clearly communicated. It would be beyond frustrating to think one completed the list to only be told one had to observe new objects. Yes, exactly what I'm trying to avoid.

Finally, he noticed the PDF list on the web site was outdated. A to-do item for us.

All that said, Mike said that he was really enjoying this program and wanted it to succeed.


I thanked Mike again. I appreciated the fantastic historical perspective. It would really help me out going forwards.

Then I made my key point. I made it clear that the Observing Committee is NOT going to make an observer go and observe new things if they worked from an older list. He definitely would not have to redo anything!

pitched some training

Sent a message to the level 1 graduates on the waiting list. Told 'em that we were planning to deliver a Stellarium intermediate level 2 course on the evening of Monday 20 September.

he let me in

Chris shared his double stars log spreadsheet with me. We disagree on colours for some targets. I wanted to collate his and Melody's observations ahead of updating the Supplemental document. Compare against mine...

learned how to script

I was bored so I taught myself how to do scripting on SIMBAD data.

I pulled the B-V values for all the double star targets in my RASC observing program! 

scripting in SIMBAD

Earlier, I had built a spreadsheet with highly customised conditional formatting to show the B-V values with the cell filled with an appropriate colour. 


This will help as I compare all the colour impressions from the early adopters including Melody and Chris.

I've no doubt some of my colour descriptions are wrong...

Thursday, September 09, 2021

have you tried turning it off and on again?

Chris SMSed me. He was at the Carr Astronomical Observatory preparing for the University of Toronto Dunlap Institute "planet party." He started asking some questions about the network and related equipment so I put my tech support hat on.

He was not seeing the SSID for the network in the Geoff Brown Observatory. He asked if it needed a reboot. Nope. That unit died a while ago so no wifi inside the GBO. Hard line recommended.

He asked about the house wireless access points. They were only seeing the library and the furnace. What? I was surprised by that. The living room unit and the garage units (times 2) should be working. I asked for more information to get context. Like where he was located on the grounds.

In the kitchen. Then he shared that the house SSID was visible but not responding to the login. Authentication error or not connecting at all. Odd. I suggested he reboot the AirCube. 

He asked if the WAP was in the super's closet. Nope. Closer than you think.

A short time later, Chris relayed things were working. Good.

Wednesday, September 08, 2021

mark your calendar

Read the article by ars TECHNICA on the James Webb space telescope. They discussed its bona fide launch date. Coming up soon! Now it's on a boat to Kourou, French Guiana, to be perched atop an ESA Ariane 5 rocket. Circle 18 December 2021!

helped with Q&A

Helped backstage with the RASC Toronto Centre Recreational Astronomy Night (RAN) meeting. I did the questions, forwarded to the presenters.


Rather surprised when the president of the centre said the CAO was closed.

returned to STF 2146 (Halifax)

Returned to Struve 2146 aka HD 156162 or SAO 30299. Still trying to wade through my confusing notes.

It's a triple. AB are very tight. In Draco.

Struve 2146 in luminance

Luminance, 0.2 seconds, 20 subs. FITS Liberator, GIMP.

C is the obvious bright star to the south-west.

I don't think I can split A and B in this image. According to SkyTools 4, the PA is 225° with a separation of 2.70"  (as of 1998). That angle is roughly the same as C.

The star west of A and north of C is J171259.2+540815 at magnitude 16.46.

First imaged this target on 25 Sep '18. Imaged again on 20 Sep '21, at a 1/10th of a second, oh, and with the SBIG sensor.

Is there a partner to C?!


WDS entry updated! There's no B. The tight companion is near C. See the 29 Aug '21 blog entry for details of the change.

pleased she agreed

Monitored the exchange between Edgar, RASC OH editor, and Matson, Naval Observatory double star rep. I was pretty chuffed. She agreed with all my proofreading suggestions.

received a list!

Computer pinged. New arrival in my inbox. How about that! A list of all RASC observing (and imaging) certificates issued to date.  My audit request had been accepted. Good.

imaged IK Peg for 2021 (Halifax)

The Burke-Gaffney Observatory was "back" from vacation. Yeh.

It imaged IK Peg for me again. Has it blown up?

IK Pegasi in luminance, for 2021

Luminance, 2 seconds, 12 subs. FITS Liberator, GIMP.

I've been shooting this for three years now...

Captures, in reverse chrono order:

Looks the same to my little eye...

Tuesday, September 07, 2021

declined October TSTM

Mr Markov asked if I might have time to present The Sky This Month at the Oct. 6 meeting.

I had to decline. Too stressed right now. 

Did let him know, however, that I had been working on the next double stars presentation, measuring again, but with a camera...

asked for spectral information

Jumped into the SkyTools forum. Asked for help.

Explained I wanted to corroborate double star member colours.

Asked if I could list from the software stars with their spectral classification (when known, of course).

Author Greg said:

Spectral classification is a lost art, and it has little scientific use today.  As a result, with a few special case exceptions such as WR stars, only the very brightest stars have spectral classifications.  Because (B-V) colors represent the same color information and are available for much fainter stars, I chose to focus on the (B-V) color index.  The spectral class is shown on the Object Info, by the way, but just isn't available for many stars.  And fainter components of even the brighter doubles will often be missing the spectral class.

He suggested use the B-V data instead. It is more widely useful. 

I assumed the B-V value shown in a list was for the primary star. He essentially confirmed that.

But he did remind us that if we select a component star in the bottom right part of the dialog, the B-V for the selected star will show in the Photometry section.

That was good. 

But I moped that I could not pull the B-V data for the secondary and additional stars into a column in the app.

turned away another

There's been an uptick in external volunteer requests to the RASC Toronto Centre. I keep having to turn people away... Too bad. We could use 'em.

Monday, September 06, 2021

started testing ST4V

After an invitation from Greg, I started beta-testing SkyTools 4 Visual, specifically the Real Time mode.

checking the computer

Using the emulator, I will be able to shake things down on John Max. But I will also try to do full testing with John Gomez directly connected to the go-to mount...

clarified sources

Clarified notes in the pending Observer's Handbook regarding the observing programs offer and their ties to the Handbook...

helped with Zoom/Ninja

Participated in the rehearsal for the RAN RASC TC. Not called OBS anymore; it's VDO.

helped member out

Took a call from a new member at the Carr Astronomical Observatory, inside the locked gate, trying to get out.

Sunday, September 05, 2021

magazine for Mom

Bought a copy of SkyNews magazine for my proud Mom. The Jul-Aug issue.

reviewed 2 log notes

Melody sent me some more double star log notes for me to review.

I thought she made a lovely sketch of 19 Lyn. I saw she was getting better at directions in the eyepiece. I complimented her on her position angles. She nailed it on HR 1887!

But she reported forgetting to drink her early morning coffee!


Saturday, September 04, 2021

asked about recognition

I've been perturbed by the lack of action from my local...

Spoke with some Toronto RASCals about land acknowledgements.

I thought it was a no-brainer but I'm wrong.

took a call from the VP

Charles Ennis, first Vice President of Royal Astronomical Society of Canada, phoned and answered my many questions about land acknowledgements and respectful recognition of indigenous peoples.

see with two eyes

I was pleased to hear he's read the entire 500+ page reconciliation report.

We also chatted about asterisms. I made sure he had access to the team dropbox folder.

explained how to get a cert

Adrian forwarded a message from a RASC Toronto Centre member who had just read their SCOPE newsletters. They asked "How does one earn the Observing Certificate?"

I sent a response. Told him I was a member of the national Observing Committee for a number of years. Then briefly described the process. Said I was also happy to chat by phone or Zoom as it could be a big topic...

answered camp questions

Answered some camping questions for Charles Y ahead of his trip to Mew Lake. Hopefully things would go something for him and other like-minded peoples there.

Friday, September 03, 2021

dove into the OH '22

After a nudge from James, I made some time to sit down and proofread the 2022 RASC Observer's Handbook. I did a deep drive into the double stars section, specifically the Double and Multiple Stars topic.

proof reading mark up

Found over a dozen issues...

Thursday, September 02, 2021

the pins

After another disturbing message, I indicated which RASC observing certificates are sent with a pin and which are not.

Maybe it is true: things are unravelling...

reassessed my plans

Cancelled my trip to Algonquin.

on it's way

Heard from Melody. For her birthday, her partner showed her a copy of an email. It documented the discussion with a company in Britain for the order of a Meade astrometric eyepiece. In fact, the order shipped. She was a pretty happy camper! I was excited for her. And I wished her a Happy Orbit Day.

Wednesday, September 01, 2021

how to proceed

With the Ontario government announcement today, I asked our A/V and speaker coordinators and the DDO chair and the CAO director their thoughts on places opening up, entrance policies, vaccine passport, etc.

group of people with masks

We've started to consider in-person RASC meetings at the Ontario Science Centre and what we'll need to do.

Complex issues.

without our knowledge

The Observing Committee learned of a certificate issued without our knowledge. That was a little bit of a shock. That's not the proper process. We must be informed.


Later we learned of another!

Are there more?!

Time for a reset.

Just when I thought things were getting sorted...


It's disturbing that this only arose because the recipient did not receive the certificate in a timely fashion. Otherwise, this might have gone under the radar.

Obs Comm update issued

The Royal Astronomical Society of Canada Bulletin newsletter arrived, the September 2021 edition. Featured my bi-monthly update from the Observing Committee.

Obs Comm section of the Bulletin

Shared the great news: we're easily broken the record for the number of certificates award in a year.

SCOPE newsletters provided

The editor of the RASC Toronto Centre SCOPE newsletter sent out a notification for new issues, times two! Lots of reading and catching up to do!


On the TC forums, I thanked the long time editor.

And the incoming editor!

Tuesday, August 31, 2021

tested spiral search

After writing some pseudocode, I deployed the spiral search function.

This is the latest version of my virtual hand controller for the IDEA GoToStar motor drive system.

VHC with spiral search button

Holy Universe, it works!

I thank Software Bisque for introducing me to the idea...

Monday, August 30, 2021

chatted about cool Vul double

Interesting discussion on Cloudy Nights, in the Double Stars forum. Someone asked about observing STF 2523 and KRU 8 and HLM 23. I shared my observation from one year ago, and the images. We all agreed it is a great grouping!

to join CAO maint. team

I was asked to help on the maintenance team for the Carr Astronomical Observatory. I agreed to lend a hand, now that some others have stepped away. The fall "mini" work party will have to be organised...

provided MC notes

Shared with Chris V all my MallinCam notes. Cautioned about unusual setup and the requirement to use the old Dell laptop with video acquisition card...

times two

Getting bogged down. A second request came in from the A/V team. I've two videos to review... Trevor Jones and Ron Macnaughton.

caught up

Caught up with one of the audio-visual team members on re-opening plans, vaccinations, 3D printing, and wind socks.

learned of a driver

The ASCOM Talk Forum digest message via rolled in. And caught my eye.

Arie B shared that he wrote an ObservingConditions driver to support various weather stations from Davis Instruments Inc.


I just might have to try that...

Sunday, August 29, 2021

WDS updated STF 2146 data

A conversation started up on Cloudy Nights. VanJan asked what was up with STF 2146. aka HD 156162 or SAO 30299. A few people chimed in. And it now looks like the Washington Double Star database was updated.


AB = 6.92, 8.80   2.8"   225°   (2018)   A9III     
AC = 6.95, 8.87   89.3"   235°   (2016)

Now (via Stella Doppie):

AC = 6.95, 8.87, 89.3,    235 (2016) CD = 8.87, 10.50, 2.8 ,    225 (2018) 

It seems the B is no more... Spurious or bad data early on and now deleted.

And it seems there's a companion at the C star, close in, 2.8" away. Ah.

That may explain why all my attempts did not reveal a B star close to A.


Did a big clean-up of the life list page. I found 2 copies, 3 entries total, for each of the pairs of Σ2146. Also, finally, put up the image from Sep 2018...


See images from:

Friday, August 27, 2021

exciting JWST update

James Webb on the move!

Read the NASA article on the completed testing for the James Webb Space Telescope.


Thursday, August 26, 2021

measured the drawtube

Disassembled the focuser on my Celestron FirstScope. Removed the drawtube. Cleaned it of the tacky thick old grease goo. Measured it.

Used my callipers and thread pitch tools.

drawtube dimensions

The rack pitch is weird. Is 17 TPI a thing?


Spent a long time on the rack thread pitch. In the end, I just manually mimicked it.

thread pitch match for the focuser rack

So that's 33 triangle trips across the 49 mm span of the rack. Or tip-to-tip over 49mm, there are 33 peaks. To get the correct pitch I used the solid pattern repeating feature in 123D with the properties of 49mm length with 33 elements within.

Then I had to remove one of the end triangles, reducing to 32 peaks, for the cutter! 

And finally I had to offset a half-tooth.

It worked! I was able to exactly recreate the weird thread pitch for the focuser rack.

That was brain-bending.

a couple more images

Submitted more photos for my next SkyNews article, due for the November release.

Sent the article in last week.

Sent a bunch of photos yesterday.

Made a diagram in Visio too. A bit meta.

Wednesday, August 25, 2021

learned cross-hair method

Back on 25 July, I attempted to use the method described by John McCue, with only a cross-hair eyepiece, to measure the separation and position angle of a double star.

At the time I could not get it to work. It seemed to me that something was missing. It was a nagging feeling as I left the web page.

Early today, I had a go using Beish's method, where he demonstrated using a custom bi-filar eyepiece with a micrometer. It got me thinking...

I returned to the British Astronomical Association web page with McCue's notes and diagrams. Built a spreadsheet (again, must have discarded the other) and hammered out the numbers.

Some light bulbs lit this time. I grokked the triangle formed by the initial cross-hair alignment and the second alignment. Trig at work. I started to get some good numbers.

I carefully read every-single-word. Spotted the remark about converting the seconds of time into seconds of angle by multiplying by 15. I did not recall seeing that before.

And then I tried working his sample values. Worked his numbers backwards. Things did not seem to align. And again, hit a roadblock. Again, it felt like something was missing. Or is McCue operating at a different level? Does "sin θ" mean something that I don't know, never learned, never understood?

I did some algebra and ended up with an equation which would solve the separation. And there it was! It worked! I had a value that matched his. Bit more brain-bending formulae and I got the separation! Holy Universe. It actually worked.

Tested it with three random doubles and was impressed. Pretty close on Albireo and HD 206224. A fair result with 94 Aquarii.

So let me try to explain the process and the maths is an obvious and easy way. McCue explanations, I feel, leave a lot to be desired.

  1. align cross-hair to EW or parallel to RA and drift a star across the field
  2. roughly estimate the position angle considering N and W in the field
  3. get time (t1) between primary and secondary stars drifting across the NS line, e.g. 1.93 seconds
  4. put the primary star at the centre
  5. align cross-hair through both stars
  6. get time (t2) of the secondary star drifting across the NS and EW lines, e.g. 3.04 seconds
  7. get the apparent/current declination (d) of the star, e.g. +28.0
  8. calculate the separation
  9. calculate the position angle

The formulae:

formulae for calculating sep and PA

Hopefully I'm using the correct nomenclature here. To be clear, the sin-1 indicates the use of arcsine.

You should get a separation of 32.1" and a position angle of 53°.

Now, McCue explains that the initial PA can impact the final PA calculation. Again, I suggest you roughly estimate it at step 4 above. If the PA is between the degrees:

  • 0 and 90, the primary will lead, and you do not need to modify the calculated value
  • 90 and 180, the primary will lead, but use a final formula: 180 - your calculated PA
  • 180 and 270, the secondary will lead, but use a final formula: 180 + your calculated PA
  • 270 and 360, the secondary will lead, but use a final formula 360 - your calculated PA

McCue also cautions that if the PA is near zero or 180, timing is very difficult.


  • you need an equatorial mount where you can toggle sidereal tracking on and off, if that's not abundantly clear
  • you'll want to work at a long focal length for greater resolution
  • a stopwatch (app) with a lap timer will be very handy
  • the alignment drifting and the timing runs should be done a few times, perhaps a dozen, to yield an average
  • if you use an electronic spreadsheet such as Excel or Google Sheets, don't forget to convert to and from radians, as required

So, there you have it.

I really wanted to work through this, understand it. It is a proof of concept. It shows that if an observer really desires to measure doubles visually and has a cross-hair eyepiece, they are good to go. 

With the dearth of astrometric eyepieces now, there are few options for the visual observer trying to save a few bucks...


If you don't want to reinvent the wheel, ask me for my Excel workbook.


Edited on 25 Aug to move "rough estimate" of PA earlier in the sequence. It's much more obvious after step 1.

Tuesday, August 24, 2021

bugs and stars

I enjoyed the photograph of the day at the Earth Science web site, EPOD.

Fireflies and star trails from Italy. Lovely shot by Elena Paschetto. She shares her photos on her instagram account.

Wish I could get that many fire bugs in my shots...

the spiral math

While listening to Hélène Vogelsinger's spiralling, looping, atmospheric, haunting songs, I figured out the math of the spiral search.

It became very clear after I made a drawing. I'll deploy the "inner ring" method first. Might be all that I need...

spirals of field of view circles

A lot fewer calculations than I first expected. 

What a neat pattern...

Monday, August 23, 2021

taught level 2 again

Taught level 2 intermediate Stellarium tonight. Good group. No issues. I successfully connected to and drive my mount. Yeh!

debugged the VHC

Decided to have a go at the Virtual Hand Controller for the IDEA GoToStar motor system.

It had crashed on the evening of 4 August. Crashed isn't the right word. When I finally got Visual Studio up and running on the laggy laptop in the backyard and then tried to launch the custom Visual Basic application, it threw a weird error.

A good portion of my time this evening was getting organised or reoriented to what I had done. The blog entry from 16 April was throwing me off because the different form layout. I had deployed the code to deactivate and activate the buttons given the port status. That was after the blog update. And I slowly remembered the decision to make it narrow vs wide. It was not that I had lost a version, thank the Universe.

Then the matter at hand, the "form1 not found" error. At last, I located the bad code in the application.designer.vb file. Updated to the renamed form object name. The app started working again, yes!

Applied a few random edits. Tried to figure out how to read the tracking status—not possible. Then searched the web for making a stand-alone program. And learned it was far simpler than I anticipated! 

For a test, I dropped the EXE to the desktop. Things were a little wonky so I closed down VS. And then it seemed to all function correctly! Wow.

virtual hand controller beside Stellarium

Look at that!

The apps running side-by-side. Er, at least easily accessible. I still have not fully thought out how to allow the apps to run simultaneously. I have pondered a virtual port possibly. In the meantime, I'll manually disconnect or close the port in one, then connect with the other. 

It works!

This'll be fun. At least, I should now be able to slew in one app and if the pointing is off, nudge and slew about in the VHC, until I get on track. And sync. Without touching the real hand controller!

Sunday, August 22, 2021

received a thank-you

Heard from Paul.

He thanked me for the mention in SkyNews! He was referring to the Sep-Oct 2021 issue.

Thank you for the plug for AstroBuySell in your SkyNews article!  Elsie says thanks too!  I enjoyed reading the article and found it to be a great ideas for folks who want to get started in imaging but need some direction.

That was nice.

photographed my focuser

Photographed my Celestron FirstScope and shared a photo with Alister. I don't see the silvery tube bit in his telescope... 

focuser on my 76 mm Newt

But I think I understand the complete ask now. The draw tube with integrated gear rack is damaged...

Saturday, August 21, 2021

most views in MI

Heard from Mark Sortzi in Michigan. He said, "I wanted to tell you that your [double stars] presentation has had 95 views on our YouTube channel, our most viewed video. Thank you again for doing that for us." Wow!

Friday, August 20, 2021

posted Aug '21 doubles list

Prepared my double star "bulletin." It is a short list of suggested targets. I shared this on the RASC Toronto Centre forum. I post here for all.


The Moon is bright again. Jupiter and Saturn are not to be missed and easily bunch through light pollution. So do double stars. Assuming you are able to locate sparklers to star hop from or align on, you can have a ton of fun.

Here’s a short selection of doubles from my life list, ones I find interesting and impressive.

staralso known asalternate catalogue(s)
HD 174897 HerΣ2411SAO 104203, HIP 92620
HD 200465 CygH IV 113SAO 70818, HIP 103822
HR 7099 AqlΣ2404SAO 104170, HIP 92475
HD 174005 SctΣ2391SAO 142640, HIP 92296
η LyrAladfar, Σ2487SAO 68010, HIP 94481

Have fun!

Blake Nancarrow 
astronomy at computer-ease dot com

Notable double star designations:

Σ = F. Struve, STF
OΣ = O. Struve, STT
β = Burnham

got a hit!

Received a nice note from Dave R.

Evening Blake, I've just gotten around to reading June's RASC Journal and I really enjoyed your article on Stellarium Mobile Plus.  It sounded really interesting.

He was interested in the full version and was prepared to buy it but asked if I had any complimentary upgrade codes left. 

I did!

One left for iOS.


Scratch all that. The reader already has the Plus edition. Didn't need the code.

So I do still have one code for iOS.

(And three for Android.)

RASC members only.

noted smoke

I looked outside. Everything was orange. Everything cast in orange light from an orange Sun. Very orange. Like on Mars. Must have been really smokey.

Thursday, August 19, 2021

enjoyed the new SkyNews

It's amazing!

The cover of the September-October 2021 SkyNews magazine is amazing. Told the editor Allendria.

cover of SkyNews Sep-Oct '21 (with bleed)

This astro-target is huge and simply wants to grow and draw us in and envelope us. With the bleed, I feel like I'm hovering in space, a couple of light-years away, soaking it all in. 

The address label is unfortunately distracting.

Image of Rho Ophiuchi  by Stephan Hamel.

cover with white border and masthead

I bought a copy at the store and the cover was slightly different with a white border and white masthead.

The theme of this issue is imaging the night sky. So, let's of great articles on imaging. I'm published in this edition with my article "astrophotography on a budget."

snapshot of web site snippets

See the online snippets at the SkyNews web site for more info.


Took me a while to understand this.

The cover with the white border is a demand of the marketing people. They want bright colours and eye-catching text so to pull in the person scanning the magazine rack. Buy now. Buy more.

The cover without the white border, well, they don't need to do The Pitch. This version goes to the subscribers. They are already drinkin' the Kool-Aid. So we get the bigger pix and smaller text. Sadly, they need to print the mailing address, hence the garish white rectangle.