Thursday, December 31, 2020

briefly thought about observing

Considered observing tonight. Looks like it might be clear for a few hours... Yes. Fun way to conclude our orbit about the Sun.



Scratch that.

Forget it...

It's a full Moon. 


onward and upward

It was Celia's last day, the last day of work by our first employee at the RASC Toronto Centre. 

I thanked her profusely. It was awesome meeting and getting to know her. It was impressive how rapidly she got up to speed, even when I threw her into the deep end. She quickly developed comfort with our systems and the dynamics of the Richmond Hill and RASC Toronto relationship. With a joyful disposition and professional manner. 

She helped me find joy in my volunteer activities at the David Dunlap Observatory. It is sad to see her go.

Wednesday, December 30, 2020

built a community space

Built a shared space in Google Classroom for the Stellarium Training Series. I wanted to offer a community environment for the training participants. Wow. Almost all the people from the first class signed in! This'll be good.

not a lot

There are not a lot of videos on viewing or imaging double stars... I've made a playlist in YouTube and there are less than two dozen. And three of them are mine!

Tuesday, December 29, 2020

on deck for DDO Observe The Sky

I'm on deck during the 23 Jan Observe The Sky event. This is a RASC Toronto Centre event associated with the Richmond Hill David Dunlap Observatory.

Celia asked if I would participate in this virtual observing event, delivering a presentation with Stellarium. Something similar to what Skylab would be during our regular DDO events. 

Originally this was planned as an in-person DDO observing event to replace the programming at the DDO as it is being renovated. The new location was the Oak Ridges community centre but it switched to virtual because of all the restrictions.


Update on 23 Jan 2021. Note: This has been renamed Up In The Sky. Richmond Hill wants to distinguish from in-person events and online virtual shows... 

Monday, December 28, 2020

taught Stellarium basics online again

Taught another level 1 course for the Stellarium Training Series.

new version out

Stellarium 0.20.4 is out. I don't know what's different, yet. I'll have to figure that out... fast. I'm teaching my intro Stellarium course tonight! Ha ha!

revisited the 2021 conjunctions

Yesterday, I made a list of planetary conjunctions. This was derived by carefully examining the Skygazer's Almanac 2021 from the Sky & Tel people. The double triangle pointers show these events. Looked like there were about a dozen events.

To cross-check this data, I thought I use my trusty ole' SkyTools 3 Professional software. Oh my... 

This is an extract from a Current Events report but I deleted the elongations and oppositions but then inserted additional annotations.

This is a listing of "Events for Toronto" but it should work for many across Ontario and beyond. All times are "local" or for the Eastern time zone and shown as military hours. 

ST3P generates a percentage darkness value which is useful for gauging visibility (see notes below).

I left the solar conjunctions in the list. Remember there's nothing to do for this kind of event but it tells you, at the same time, that the planet in question will not be visible.

The S&T events I italicised in this list.

  • Jan 9, 23:10 - Mercury and Saturn 1.6° apart, Alt=-55°, 95% Dark, Jupiter is a bit further away, higher up, so makes a triangle; should be visible after sunset *
  • Jan 11, 13:35 - Mercury and Jupiter 1.4° apart, Alt=26°, 0% Dark, now Mercury is passing Jupiter so Saturn is further away, lower down; Saturn is a mere 11° from the Sun! *
  • Jan 20, 13:23 - Mars and Uranus 1.6° apart, Alt=20°, 0% Dark, view after sunset, well up, visible in binoculars, first quarter Moon is close by... ***
  • Jan 23, 22:02 - Saturn in Conjunction with the Sun, a good reminder that the planet is transitioning from the evening sky to the morning...
  • Jan 28, 20:40 - Jupiter in Conjunction with the Sun
  • Feb 6, 01:52 - Venus and Saturn 23' apart, Alt=-54°, 95% Dark, I think this will be very difficult or impossible in the bright morning sky, even though Venus is bright, partly because the planets are a mere 12° from the Sun, also they're below the ecliptic, and the ecliptic is canted!
  • Feb 8, 08:48 - Mercury Inferior (solar) Conjunction
  • Feb 11, 09:36 - Venus and Jupiter 26' apart, Alt=21°, 0% Dark, again, an extremely difficult event to view even though we're talking about the two brightest planets; possibly visible in the day-time although great care must be employed, particularly since the planets lead the Sun!
  • Feb 12, 16:00 - Venus and Jupiter 1.4° apart, Alt=7°, 0% Dark
  • Mar 5, 00:55 - Mercury and Jupiter 19' apart, Alt=-50°, 95% Dark, while the planets are below the ecliptic and the ecliptic is canted low (in spring time in the morning), they are 27° ahead of the Sun, as viewed around 6:30 AM! *
  • Mar 10, 19:02 - Neptune in Conjunction with the Sun
  • Mar 13, 23:08 - Venus and Neptune 22' apart, Alt=-48°, 95% Dark, sounds cool on paper but impossible to view given the Sun's proximity
  • Mar 26, 02:58 - Venus Superior (solar) Conjunction
  • Mar 29, 23:28 - Mercury and Neptune 1.3° apart, Alt=-50°, 79% Dark, a non-event, I'd argue, as we're talking faint planets, canted ecliptic, and both are below the plane
  • Apr 17, 06:20 - Moon and Mars 1.3° apart, Alt=-21°, 25% Dark, a lovely pairing with the crescent Moon phase, view after sunset where they will be about 5 or 6° apart, should show Earthshine... ***
  • Apr 17, 07:39 - Moon and Mars 58' apart, Alt=-15°, 1% Dark
  • Apr 18, 21:49 - Mercury Superior (solar) Conjunction
  • Apr 22, 21:10 - Venus and Uranus 14' apart, Alt=-4°, 60% Dark, this looks to be challenging to me with a bright sky at sunset, the planets are close to Sol at 7°, and Mercury below!
  • Apr 24, 01:58 - Mercury and Uranus 44' apart, Alt=-31°, 81% Dark, it would be very interesting if we could turn off the Sun for a moment, a neat triangle of with Venus
  • Apr 25, 13:10 - Mercury and Venus 1.2° apart, Alt=62°, 0% Dark, might be visible given the brightness of these two planets but they will be very low to the horizon *
  • Apr 30, 15:53 - Uranus in Conjunction with the Sun
  • May 12, 19:58 - Moon and Venus 1.1° apart, Alt=16°, 0% Dark, ooh, a razor thin Moon will be below Venus **
  • May 15, sunset - Moon and Mars, additional entry manually added! a waxing crescent Moon will be attractively close to the red planet ***
  • May 16, 01:51 - Moon and Mars 42' apart, Alt=-11°, 95% Dark, further away this evening **
  • May 28, 23:11 - Mercury and Venus 24' apart, Alt=-9°, 94% Dark, 16° trailing the Sun, but the sky will be bright after sunset **
  • Jun 10, 21:13 - Mercury Inferior (solar) Conjunction
  • Jun 11, sunset - Moon and Venus, additional entry manually added! a very thin Moon will be attractively close to the bright planet ***
  • Jun 12, 02:43 - Moon and Venus 38' apart, Alt=-21°, 95% Dark, further apart this evening **
  • Jul 11, sunset - Moon nearing Venus and Mars, cool horizontal alignment, lovely! ***
  • Jul 12, sunset - Moon leaving Venus and Mars, still lovely! Venus and Mars close! ***
  • Jul 13, 09:32 - Venus and Mars 28' apart, Alt=13°, 0% Dark, the second planet is moving away now from the fourth but it is still a great view, arguably for a few days... **
  • Aug 1, 10:07 - Mercury Superior (solar) Conjunction
  • Aug 18, 23:19 - Mercury and Mars 4.3' apart, Alt=-23°, 82% Dark, fantastically close together, each planet, but the sky will be bright at sunset, and while the planets are over 15° from the Sun, the ecliptic is canting low now in the west, probably telescopic only **
  • Aug 28, 07:21 - Moon and Uranus 1.8° apart, Alt=54°, 0% Dark, this will be an easy binocular event from early evening and past midnight **
  • Sep 24, 13:52 - Moon and Uranus 1.8° apart, Alt=-26°, 1% Dark, a bit too wide for binoculars, so perhaps a test of unaided eye observing, works one night later too... *
  • Oct 8, 00:02 - Mars in Conjunction with the Sun
  • Oct 9, 12:18 - Mercury Inferior (solar) Conjunction
  • Oct 9, 16:04 - Moon and Venus 1.9° apart, Alt=25°, 0% Dark, here's a great day-time viewing opportunity! binocular target, naked eye target, trailing the Sun by 45 degrees, I love seeing planets in a blue sky ***
  • Nov 3 - Moon occults Mercury, 0% Dark, this is a neat day-time event, with such an old Moon, but there's a dangerous element to it, with the celestial bodies 15° away and ahead of the Sun—BE CAREFUL! ***
    • 15:35 - First Contact, Sep=+00°16'37", Alt=20°
    • 15:35 - Second Contact, Sep=+00°16'31", Alt=20°
    • 16:04 - Mid-occultation, Sep=+00°10'00", Alt=16°
    • 16:32 - Third Contact, Sep=+00°16'29", Alt=11°
    • 16:32 - Last Contact, Sep=+00°16'34", Alt=11°
  • Nov 4, 01:20 - Moon and Mars 1.7° apart, Alt=-55°, 95% Dark, not visible in Ontario
  • Nov 8, 01:02 - Moon and Venus 44' apart, Alt=-57°, 95% Dark, thin Moon after sunset should be attractive, while the objects will be low, plus below the ecliptic **
  • Nov 9, sunset - Moon joins Saturn then Jupiter, over three nights, a pretty scene in a dark sky ***
  • Nov 10, 10:26 - Mercury and Mars 58' apart, Alt=33°, 0% Dark, a challenging morning event, actually happening over a couple of days, with the planets a short 10° ahead of the Sun
  • Nov 17, 22:56 - Moon and Uranus 1.8° apart, Alt=60°, 0% Dark, woo hoo, binocular range through most of the evening ***
  • Nov 28, 23:39 - Mercury Superior (solar) Conjunction
  • Dec 2 - Moon occults Mars, 94% Dark, the occultation proper is not visible for humans in Toronto, but during the pre-dawn of the 2nd, the old Moon will be a short distance from the angry planet *
    • 19:55 - First Contact, Sep=+00°16'29", Alt=-45°
    • 19:55 - Second Contact, Sep=+00°16'25", Alt=-45°
    • 20:18 - Mid-occultation, Sep=+00°02'42", Alt=-49°
    • 20:40 - Third Contact, Sep=+00°16'24", Alt=-52°
    • 20:40 - Last Contact, Sep=+00°16'28", Alt=-52°
  • Dec 4, 06:07 - Moon and Mercury 29' apart, Alt=-18°, 80% Dark, impossible/dangerous
  • Dec 15, 03:30 - Moon and Uranus 1.7° apart, Alt=8°, 0% Dark, again, a great binocular target, and have a go at unaided observing ***
  • Dec 31, 16:13 - Moon and Mars 1.7° apart, Alt=-15°, 0% Dark, ooh, neat, a thin old Moon will rise into the pre-dawn sky leading Mars, visible in binoculars which yield a 5 degree or bigger field of view ***

Bear in mind these times highlight the moment of closest approach or minimum separation and at that specific time, the object(s) might be below our horizon (hence the negative altitude values). Still, leading up or just after might afford a pleasing view.

I also checked all these events in Stellarium...

So, what's the point of all this?

Part of it is to show that conjunctions, by themselves, are common. The speedy planets like Mercury and Venus, along with the Moon, make for many alignments and appulses. Over 25 interesting events!

But, clearly, the Sun's position is a factor. This cuts down from the pure, mathematical instances to a short list of viable ones we can see or image.

So I've used asterisks as the indicator of good things, my personal ranking. One asterisk (*) for a mediocre event; three stars (***) for a very neat event that you should add to your calendar.

ARO renewed me

Received a message from the robot at the Abbey Ridge Observatory.

Subject:  ARO Robotic Telescope message
Message:  #arosays  Your observer account has been renewed!  It now expires on 2021-12-28.  You are a member of the 'Power Observer' observer group.

Thanks, robot!

Halifax, we had a problem

I tried to image 11 LMi again. I had decided to shoot faster than I did on 5 May '18, twice as fast. Was trying to route out the faint companion star.

But something went terribly wrong...

11 LMi double star trailed

Luminance only, ½ second subexposures, 20 stacked shots. FITS Liberator, GIMP. North is up; east is left.

Looks like one of my light painting images...

Sunday, December 27, 2020

imaged NGC 2266 (Halifax)

While I was watching a new Netflix movie, the BGO captured NGC 2266, one of Blair's open clusters... I tried to view this one in the 3½" a while back and I could barely see it.

faint open cluster NGC 2266

Luminance filter, 5 seconds, 12 stacked shots. FITS Liberator, GIMP. North is up; left is east. 

This faint open cluster location in the constellation of Gemini is best viewed in November and December.

Some data from SkyTools 3 Pro. Also known as Collinder 113, Melotte 50, Raab 38, and OCL 471. Magnitude 9.5, size 5 arc-minutes, and at a distance of 11000 light-years.

The large rectangle above (north) with the star in the middle I had viewed at low power with the Meade ETX in April (and it reminded me of a dipper) but I had not got a good look at the cluster. Most of the members in this cluster are in the magnitude 12 and 13 range.

check for conjunctions

The 2021 planetary conjunctions, just FYI...

Dates approximate. Evening times unless otherwise stated.

  • Mercury, Saturn - 9 Jan
  • Mercury, Jupiter - 11 Jan
  • Mars, Uranus - 21 Jan
  • Mercury, Mars, Uranus - 22 Jan
  • Venus, Saturn - 6 Feb
  • Venus, Jupiter - 10 Feb
  • Mercury, Jupiter - 5 Mar
  • Mercury, Neptune - 30 Mar
  • Mercury, Venus - 28 May
  • Venus, Mars - 12 Jul
  • Mercury, Mars - 17 Aug
  • Mercury, Mars - 9 Nov

There's a couple in the future!


I made a much better list...

tried to find SEI 10 (Halifax)

It was a bright Moon but predicted to be clear in Halifax. So I loaded in a "neglected" double star target for analysis. SEI 10 or more formally WDS 00589+3230SEI 10. I chose the nearby star GSC 02281-0256 to centre the field of view. The BGO Robotic Telescope replied when it completed the observation.

region around dubious double star SEI 10

Red filter, 3 seconds subexposure, 12 stacked shots. FITS Liberator, GIMP. North is up; left is east. 

The 1x12 luminance image showed some strange artefacts...

SEI 10 has but one observation from 1894. It is listed with a PA of 100° and a separation of 12.4". The purported magnitudes are 9.5 and 10.0. The precise coordinates is 005853.67+323038.6. The comments field showed "NX." Oh oh. "Dubious double." Specifically it said "Neither component seen on POSS plate" and there "may be flaws on AC Potsdam plate."

The GSC target star in the centre is very faint at mag 14.3.

The brightest star in the field, at the 8 o'clock position, a bit south and east of centre is HD 5704. It shines at magnitude 7.4.

Stars in the mag 10 range are to the north-east, widely separated, and to the south-east, vertically oriented. The wide pair at the bottom-left are 61 seconds-of-arc apart with a position angle of 185.

Intriguingly, there is a faint double below centre in the Burke-Gaffney Observatory image, not shown in SkyTools 3 Professional. The software chart only shows a single point at this location, for J005855.0+322642, a mag 14.1 ember. Even so, the vertical orientation suggests a PA around 180. I estimate the sep at 20".

So, at this stage, this is inconclusive. There are no obvious tight mag 9 or 10 stars in a left-to-right orientation...

picked up Sky & Tel

Picked up the January 2021 Sky & Telescope magazine, once again. From my local Shoppers store. I was after the unique hourglass almanac, as usual.

I'll give the cover article a read. Adam Block will share tips on imaging galaxies. Need all the help I can get.

cover Sky and Telescope magazine Jan 2021

Reviewing the Best Events piece will be good, so to augment my astro-calendar for 2021.

I'm also looking forward to the new column, the Suburban Stargazer. How many of the readers would classify themselves, I assume.

posted late-Dec 2020 doubles

Prepared my double star "bulletin" for Dec '20-Jan '21. It is a short list of suggested targets. I shared this on the RASC Toronto Centre forum. I post here for all.


Keep an eye on your weather tools and if we get a rare clear night, bundle up and get outside. Any astronomical observing is better than TV. Here are some fun and interesting double stars which are not terribly tight or faint.

staralso known asalternate catalogue(s)
χ (chi) TauΣ528 (Struve), 59 TauriSAO 76573, HIP 20430
HR 9094Σ3053 Cas (STF)SAO 10937, HIP 207
MeissaΣ738, λ (lambda) or 39 OrionisSAO 112921, HIP 26207
HR 3174Σ1183 in MonocerosSAO 135505, HIP 39675
θ (theta) PerΣ296, 13 PerSAO 38288, HIP 12777

Bonus: since it is so beautiful. And we need a bit of joy.
HR 2764 CMa aka h3945, 145 Canes Majoris, SAO 173349, HIP 35210

Doubles can punch through some light pollution and you can enjoy while the Moon’s out. And while you’re checking out planets like Jupiter and Saturn before they fade away or Mars as it gets smaller and smaller.

Be seeing you.

Saturday, December 26, 2020

saw a good article!

Found an article with USA Today entitled Fact check: Images of Saturn, Jupiter are real, taken from Massachusetts telescope. It's good to see that some news outlets are trying to validate astronomy posts. Yeh.

received gifts (sorta)

Received some fun astro gifts for Xmas 2020.

A nice card from J, B, and J. Stars in that snow globe!

Cool socks! Apropos for the recent conjunction.

From Rhonda, another wonderful ceramic piece from Place of Grace Pottery. I have the large mug from my 2019 birthday but this is a bit bigger. Hmmm, might fit a pint!

Rocket socks!

Ooh. Neat tumbler for wine. Reminds me of camping.

And during the family Zoom meeting, Mom "unwrapped" a present for me. A new book about the Hubble Space Telescope by Jim Bell. Back in 2015, she gave me another book on Hubble.

Thank you!

Thursday, December 24, 2020

spotted peculiar icons

Weird. I just checked the Clear Sky Chart for the Abbey Ridge Observatory (ARO) to see if the skies might be clear again.

strange icons on Clear Sky Chart for Dec 24

Some icons, undocumented, are showing on the chart... Huh. A bug? A gremlin? A slight disorder?

imaged the tree (Stillwater Lake)

Back on 3 Dec, I queued up a MRO job, aiming at SAO 114273 which was in the middle of the target. Funny timing...

NGC 2266 and friends in Monoceros

Luminance filter, 15 second subexposures, 12 stacked shots. FITS Liberator, GIMP. Note! North is down; left is east. I.e. it's vertically flipped. Also, full frame requested.

Mini-Robotic Observatory captured a nice wide field.

Lots going on here, of course. 

NGC 2264, the Cone Nebula, the "Christmas Tree" cluster, the Fox Fur nebula, double stars, etc.

The Cone Nebula is also known as NGC 2264, Sharpless 2-273, LBN 911, and Bernes 97. The cone proper is faintly visible at the peak of the tree. It contains the catalogued dark nebula globules NGC 2264-1 and W 75.

The open cluster is aka Collinder 112, Melotte 49, and OCL 495.

15 Monocerotis, the multi-star system is here, starting at the "trunk" of the tree and the brightest star in the entire field. Back on 18 Mar '17, I imaged the double star complex with the BGO rig and Apogee CCD.

Double star STF 3118 is the equilateral triangle to the east of 15 Mon.

Struve 954 is the double star at the top of the tree. The brightest member is the star at the apex of the near the tree. B is barely visible, at the 11 o'clock position, extremely close to A, in the glare of A. The C element is beyond, further to the south-east. Over to the south-west, two to three times the separation is bright D. South of D is E.

The Fox Fur nebula is up and right of 15 Mon. See wikipedia for more info.

Σ951 aka V684 Mon is in the middle of the Fox Fur. B is plainly visible at the 4 o'clock position or north-west. C is remarkably tight to B, south-west of B. D is easy, south-east of A, well away. E is easily spotted while dim, west-north-west of A, the same distance as D.

South-east of the cone is double star J 39. It is an unequal pair with faint B almost due north, below. [ed: Retraction. Misread the software chart. J 39 is a tight double at 1.8". That's a field star...]

West of 15 Mon is another globule, NGC 2264-3.

A lovely dense part of the Milky Way. You can see this is a dusty region, lots of stuff is being blocked...

Weird shadow in the frame. Big dust mote, in the 'scope, not in space.

All of the stars seem to have a glow. Bad transparency? Dew?

Wednesday, December 23, 2020

hacked the t-ring

I hacked the t-ring for the Canon EOS camera. 

I had always noticed some play in the t-ring but didn't think much about it until recently. The recalled the issue during the Jupiter-Saturn conjunction event I participated in even though the slop was not a factor for the planetary live views.

Where did I buy this generic ring? Couldn't remember. Clearly sometime shortly after coming by the Canon digital single-lens reflex in 2012.

Back in June this year when I was imaging in Vulpecula for double stars, I thought, "This is bad." The slight rotational play in the t-ring and the camera body meant the camera angle could change. That must not be allowed to happen if attempting accurate position angle measurement with the camera on the telescope. (And if it does happen, one must then calibrate each photo!)

Today I did some quick research into the matter. A Google search on the phrase "play in t-ring" yielded a few interesting hits.

The first was for the Baader Planetarium zero-tolerance protective Canon DSLR T-Ring available listed on the Ontario Telescope website. I had a look at the product page and pictures. It sounded like it was made to exacting tolerances to reduce both rotational and octagonal shifts. 

The octagonal issue is important to imagers after perfectly flat fields. I experienced this issue with my image of Albireo, the double star, in late 2012 which Dietmar analysed to in fact show just how much the camera was not square.

I followed another link from the search engine results page, this time landing in a Cloudy Nights discussion. Back in April, in a thread titled Canon EOS T-Rings that don't wiggle, people were talking about solutions. Different t-rings were discussed with remarks on fitment.

Perhaps I need to get a high-quality t-ring. The Baader unit is not inexpensive. Would it fit the 40D?

All this got me thinking... 

Grabbed the 40D body and t-ring. There didn't seem to be discernible tilt (I still wonder if the flat field issue with beta Cygni was due to sag). However, the rotational play I eyeballed at about one degree. Could I get rid of this?

Suddenly, I thought, "What about a gasket?!"

I tripped to the kitchen in search of some elastic bands. When unwrapping various grocery products, I keep the rubber bands, tossing them to a shelf by the sink. Happily, I found a pile. I retrieved them all and returned to the workshop. I was very pleased to have some fine, small bands that looked rather promising. I slipped a thin blue band into the track of the t-ring and remounted the assembly to the camera body. 

t-ring with rubber gasket

Holy Universe! It worked! Wow. The t-ring was now very snuggly held in place. There was no play due to the compressive band. The rotational resistance was now so great it was in fact easy to unthread the nose piece from the ring.

I think this will work very well. Another hack completed, solving a nagging problem with imaging. Better, more consistent results are in store for double star projects.

This simple fix has eliminated the rotational problem. Perhaps it will help with octagonal alignment but I'm less concerned with that.

Tuesday, December 22, 2020


Back inside. Everything's back inside. We tried...

high hopes

Gonna try... Big, fast-moving clouds. But I'll set up and we'll see what happens...

Monday, December 21, 2020

two points not one

Rhonda and I discussed the conjunction. She was rather upset and I was a little surprised. "The planets didn't form one point! They were still really far apart!" I agreed and said that I had been trying to clarify that to others. They were not going to merge.

I pointed out that even fellow astronomers were saying they were going to form a single point of light. No. No closer than 6 arc-minutes, above the limit of human vision resolving power, even at night. I did the research. I consulted with an expert.

And of course, under high magnification in a telescope, they would be well separated. 

She was very upset. But I attributed it to misrepresentation by the media. The whole "Christmas Star" thing I thought was silly, they weren't going to merge, and it wasn't going to get incredibly bright. Bad reporting by journalists without a science background and "selling newspapers." 

It was interesting and off-putting her anger. But it reinforces what I've been feeling for a long time. The news outlets are crying wolf and it will upset viewers leaving them disenchanted in the future. A further erosion of trust.

reported a violation

Discovered one of my double star images on a Canadian astronomy group's YouTube channel, used without my permission. In fact, it was used as the thumbnail image on five of their videos. 

I pointed out the copyright violation but offered that they could use it with credits and links. They removed the thumbnail from the videos in question. Later a follow-up private email was sent with apologies.

They said tried to use images on public domain sites like Wikimedia Commons or Public Domain Pictures, etc. but sometimes weren't sure of the source. Such a slipshod approach might get them into more trouble. 

In fact, they appear to have taken copyrighted infographics for their Jupiter-Saturn conjunction video from USA observatories and USA news agencies without credits or courtesy notices. The owners might not take lightly to that.

I understand Fair Use situations and use by a non-profit but I believe it still very appropriate and considerate for sources and credits to be shown.

checked the split limit

I've been seeing and hearing about an aspect of the conjunction of Jupiter and Saturn that doesn't sound right. Purportedly, people are saying the two planets will merge to form one point of light. I don't think so.

Let's do a comparison. 

Mizar and Alcor are separated by about 12 minutes of arc (').

Mizar and Alcor at 12 arc-minutes separation

Jupiter and Saturn today at 6:37 PM Universal Coordinated Time will be about 6 arc-minutes apart.

Jupiter and Saturn 6 arc-minutes apart

The Moon, as previously discussed, is around 30 minutes.

From Observing and Measuring Visual Double Stars by R.W. Argyle (second edition), it is stated:

A normal pair of eyes should be able to see... 5.5 minutes without difficult and some may be able to make out... 3.6'.

This matches up with a very old note that I had.

The closest separation the eye can distinguish about 4 minutes of arc.

So, to conclude, people with good vision will be able to "split" the two planets. In other words, they will not merge.

A new vision test...


Updated from Dr Ralph Chou.

The "normal" minimum angle of resolution of the eye is 1 arc-minute - that is what is referred to as 20/20 vision.  Many young adults have 20/15 vision, a MAR of 0.75 arc-min.  [That] is for daylight-adapted (photopic) vision.  With dark adaptation, rod vision comes to the fore, and the MAR will become larger.  A limit of 4 arc-min seems reasonable for mixed rod and cone vision in mesopic conditions that are more typical of a city nightscape.

There you have it with 4' being reasonable.

spotted the fun doodle

Ha ha. Google's animated doodle features Jupiter and Saturn high-fiving.

Happy conjunction every one.


Google provided links for humans in the northern (where it's winter) or southern (summertime) hemisphere.

Sunday, December 20, 2020

clinic cancelled

We cancelled the Richmond Hill new owner's telescope clinic. With the lockdown situation, it meant that an in-person event could not proceed. The RASC DDO chair advised we switch to an online or virtual format. I'm not sure how to do that. I'll see if anyone wants to join me on a working group to plan it...

watched the Exeter event

Watched the joint Exeter university and Exeter Science Centre webcast live stream of the conjunction. They had clear skies in the UK. Closer still! Good group of panels, speakers, operators, and hosts although professor Bates bumbled a bit. Fighting clouds, they did occasionally get some great views. Neat the infrared and low-light cameras they had on the rooftop. The YouTube chat though was a mess. A lot of trolls which they did not wrangle. That made for a sad note on an otherwise interesting event.


Saturday, December 19, 2020

to try a zoom

Bing. A new thought entered my old brain.

What about a zoom eyepiece?! 

It occurred to me that using a zoom eyepiece in the telescope while observing double stars might be helpful, handy, and a big time-saver. Often a double star observer is up and down through the eyepiece case.

I always try to start at low power, assess, and magnify up as needed. But currently that means swapping eyepieces. That's OK, by itself, a little fiddly in the dark but not a big deal. 

More importantly, I find myself often detaching and reattaching heating straps. That's a big deal. I don't like all the stress and strain going into the wraps.

If I can find out then I could shake it down, see if it is truly efficient and less fiddly, and see if I like the views. And keep the dew fighting heat in the same glass. Historically, zoom oculars got a bad rap in terms of optical quality. But they sound much better these days. 

If a zoom eyepiece had a poorer view than my existing eyepieces, say it was soft at really high power and I was trying to split a tight pair, I could still flip to a regular one. It's not that I'm using top-drawer eyepieces...

Neat idea.

Wonder if I can borrow one... 

looked for rag

Looked for the new Sky & Telescope magazine at my local. Nope. Very old one...

Friday, December 18, 2020

a personal goal

I was reading the latest SkyNews and neared the end of the magazine. 

Spotted RASC president Robyn Foret's closing remarks, including his resolutions for 2021.

Among other things, within his personal observing goals, he wants to do the new double star programme.


learned RH councillor arrested

It was with some irony I read about partners-in-crime Karen Cilevitz and Derek Christie being arrested. When I dealt with her in person, many moons ago, she seemed fine. When she "chained" herself to the DDO cause and become a Richmond Hill councillor, it became clear she had a skewed perspective. She and RASC parted ways. I remember seeing her standing on the outer catwalk at the DDO grand reopening event, proud as a peacock, like she had something to do with it. Now we are seeing their true colours.

helped with the live stream (Bradford)

Another good night!

This time I went out to participate in the RASC Toronto Centre live stream YouTube event. Another ad-hoc event coordinated by Andrew.

3:59 PM. Sun was nearly down. Moon was obvious but behind the trees for me. Very clear skies!

Electrical hooked up. Vixen installed with last night's polar alignment. Again with three counter-weights. Eyepiece case. Kit bag with camera and specs. Various cables. Grabbed Rhonda's old chair in addition to the astro-chair.

Didn't know where my compass was. Not that I needed it tonight...

Grabbed the chilled OTA, with finder in place. Unwrapped the baader eyepiece, still in the WO mirror diagonal, and installed it in the WO focuser. Dusted off the dropped cap. Powered the mount. Skipped a star alignment. Slewed to the Moon and turned on tracking.

The bunnies were watching me.

4:04. Headed inside for the netbook, power supply, winter coat, and phone.

Installed the camera and its external power supply. Connected John Repeat Dance to the DSLR. Powered the netbook. Ran two jumpered 50-foot ethernet lines and plugged into the hardline. Fired up the Canon EOS Utility. And it froze. Restarted Windoze. 

telescope-camera setup for live streaming

My office. Motorola, Android, f/2, 1/30 second, ISO 66, HDR. Before the additional laptop was brought out and set up...

4:23. The netbook acted better. EU started correctly. Focused on the Moon, first moving the primary, then using the external. Started Zoom on the phone. Checked Evernote for the shared screen link.

Tried to run OBS Ninja but it didn't work. Tried to install Brave 32-bit. Didn't work. Kricky. Plan B, I thought.

Fetched the laptop, its power brick, the Canon software CD, and a USB cable to keep the phone alive. Started installing the EOS software to the laptop.

4:39. I was admitted to the Zoom session on the Android. Andrew and Rick were up and running. In fact, Rick was already on the planets. Rick could see the shadow of Io on the Jupiter! I could not see the two gas giants visually yet.

Activated the Ninja link on the laptop as the Canon installer continued. It wanted a reboot. Uh boy.

[ed: Missed the message at the time. 4:43. Phil C pinged me. The Great Red Spot was to transit at 5:30 PM.]

Realised I could use the netbook as the information console. Launched SkyTools to get the distance of the Moon to the planets. Slightly down from the Moon and 20° to the right. One Hang Loose away. Still couldn't see the planets...

4:56. Finally started EOS Utility. I had a working setup! Turned on live view. Nothing in the field. Must have drifted off from the Moon. Slewed. Andrew could see it. He readied to start the live event on the RASC TC YouTube. 

I checked the camera. Oh. I was in C3; switched to C1. That explains why I've been getting the weird message about live view being disabled... Worked the focus.

Checked for the planets. Got 'em! Clear sight line for the telescope rig. w00t! Slewed by RA—there they were. Centred in the finder. Two minutes to go-live. Saw a planet on the sensor. Slewed at slow speed. Holy Universe! A great view.

Touched up the focus. I rotated the camera a bit. 

Andrew started the 'cast. Introduced everyone. He shared the views of his, Rick's, and my camera. I did some commentary.

Clarified that on the 21st they will be 6 arc-minutes apart but discernible to the eye as two points.

Claudio started joining in.

I shot some photos along the way. Common telescope-camera details. C8, f/10, external focuser, manually focused, tracking, not star aligned, Canon 40D, daylight WB, RAW. For all, north is up, east is left.

Saturn and Jupiter closer together

5:19. ISO 1600, 1/4 second. About 20 arc-minutes apart. Yes! All four moons for Jupiter. Left to right: Callisto, Ganymede, Europa, and Io. Titan is just barely visible, 2:30 o'clock position.


Shared the distances. Jupiter around 880 million kilometres from the Earth while Saturn was 1.6 billion. So about 700 million km apart in space.

Answered some questions relayed from the YouTube chat.

some planet details on Saturn and Jupiter

5:23. ISO 800, 1/60 second. Wanted a quick exposure to not blow out the planets.

We talked about the elevation or altitude above the horizon. 14 degrees at the moment. We talked about seeing conditions. I thought it was good seeing. A bit better than last night.

Talked about how the EOS software worked. And that the 40D is not modified.

So amazing.

many moons of Saturn and Jupiter

5:37. ISO 800, 10 seconds. Did a long shot to coax out for Saturnian moons. Dione and Rhea are roughly inline with Titan, on same side. Dione is the closer of the two. Tethys is visible to the left of Saturn, just off the rings, half the distance of Dione, about the 8 o'clock position. I think Iapetus is out of frame... The bright star below Jupiter is HD 190821.

5:43. Subsequent photos showed diffraction from the tree branches. I was done.

Rick showed the Moon for a bit. I some a glow around the Moon from thin upper cloud.

6-ish. We wrapped the live broadcast. 

Viewers from Calgary and the US and A. Some local RASC peeps. Cool! 

I thanked the team. And Betty. Stopped the Zoom.

I was cold.

Rhonda arrived home. She had seen the planets while driving.

Did a very fast teardown.

6:05. Removed the Vixen Super Polaris and headed indoors. The mount and GoToStar worked great. Amazingly well for a rough polar alignment and a zero-star alignment. Ha!

A good run. We've been very fortunate with this weather. The prospects for Monday 21 December are not lookin' good though...

6:30. Oh! Remembered my portable weather station this time. Precip tomorrow, air pressure steady, 45% relative humidity, -5.5°C air temperature.

Raw video recording of the live stream is available for viewing.


Andrew talked about his doubler. I just checked SkyTools. I'm in "the doubler zone" starting tomorrow night...!


I must dub the Windows 10 laptop. You shall be known as John Gomez.

Thursday, December 17, 2020

they offered live views

Meanwhile, Andrew, Claudio, and Rick shared live streamed views of Jupiter and Saturn on the RASC Toronto Centre YouTube channel. Ward and Betty supported the live ad-hoc event. Great stuff!

viewed and imaged Jupiter and Saturn (Bradford)

Got 'em!

Around 4:15 or 4:30. I wasn't convinced the skies would be really clear when I saw a bunch of cirrus feathered clouds on high and low thick clouds over the western horizon. From the driveway I spotted the crescent Moon. Couldn't see the planets. 

Went indoors to check the weather websites. The cloud bank was hovering just to the west, wiggling back and forth. But then I thought, "you don't want to miss this."

When I returned outside with the eyepiece case, things had improved! Yes!

Quickly set up the Celestron 8" Schmidt-Cassegrain Telescope atop the Vixen Super Polaris supercharged with the IDEA GoToStar system on the levelled tripod. Installed the baader planetarium aspheric 36mm ocular. Installed the finder scope. As I hooked up the heavy-duty extension cord, I bumped into Rhonda. Energised the mount and aimed at the planets. 

Oh. My. Universe. 

Saturn and Jupiter in the same field of view! It was awesome!

Shared the view.

I explained the historical significance of the event. We were among the first humans ever viewing with magnification or photographing these planets so close together.

Exhilarating. Good detail on Jupiter. Only three moons though. I knew the distant one was Callisto. I wondered if the bright one was Io. Could see a big barge near the meridian.

Saturn and its rings were lovely. As the sky darkened, Titan emerged, beyond the east edge of the rings, toward Jupiter.

Rhonda asked me how far apart the planets were in space. I didn't know the numbers off the top of my head and we cancelled the huge download update for SkySafari Plus on her phone. I said it was significant, millions of kilometres. [ed: Jupiter is 5.9 AU (Astronomical Units) from the Earth or 882 million km; Saturn's distance is 10.8 AU or 1.615 billion km. The difference is 732 million km.]

We talked about the brightness. I gathered she had read something that said the planets would be incredibly bright in the sky on the 21st. Ah. No. Only slightly brighter than Jupiter was currently... [ed: On Dec 21 at 6:00 PM for Ontario, Jupiter and Saturn's extincted magnitude values will be, respectively, -1.17 and 1.43. I calculate the combined mag at -1.3.]

What an amazing sight in the 1° field of view. Wow.

The seeing was fair, not as bad as I thought it was going to be.

I was a little surprised how far apart the planets were in the sky. A pinkie fingernail. To the right of the Moon and down slightly. A beautiful scene. Magnificent earthshine.

Fetched the camera to do a test shot but before hooking it up, I swung to the Moon. Crisium was on the terminator. It made the uneven lava flows in the maria floor very obvious. Along the north pole, there were two isolated white dots, mountains peaking into the sunlight. Long shadows everywhere. 

Grabbed the t-ring and nosepiece.

Installed the camera and focused moving the primary. Fine-tuned with the Williams Optics Crayford type focuser. Tagged Saturn. Hunted around and bumped into Jupiter. Rotated the camera and panned some more. Wait! What! There they are! I couldn't believe it when I saw both on the sensor. But they were faint on the live view... Decided to take a shot.

Common camera settings. C8, f/10, external focuser, manually focused, tracking, not polar aligned, Canon 40D, ISO 1600, 10 seconds, in-camera long exposure NR off, daylight WB, RAW, manually triggered, 2 second self-timer. For all, north is up, east is left.

Converted with DPP Not processed.

Saturn and Jupiter in conjunction - with some moons

5:54 PM. Image 526. Hey! Moons! 

[ed: Callisto is between Saturn and Jupiter. The bright moon to the right is Ganymede. The outlier is Europa. Io hidden... Jupiter distance from the Sun: 33° 21'. Jupiter from Saturn: 26' 12". Jupiter's altitude above the horizon: 10° 59'.]

Panned a smidgen.

Saturn and Jupiter in conjunction - in the trees

5:55 PM. Image 527. Dimmer. The planets were dipping behind the trees in the west edge of the lawn.

Saturn and Jupiter in conjunction - in the trees

5:56 PM. Image 528. Soft and fuzzy, due to the diffraction. 

I had left it a little late but it was just a test. Now I know I can image the two planets together.

Wow. What a sight. A big one for the life lists...

Not that cold. Low humidity.

Remembered to polar align before tearing down. OK. So that was an excellent test session. Optically, everything is fine, planets are "in range" of the camera, I'm in a good spot on the lawn, and the Vixen is polar aligned. I'll be ready for the next clear night!

Wow. Very happy I pushed through the laziness.

"Witness me!"


made a conjunction video

Andrew, Chris, and I rolled out our latest Astronomy In Depth video. This time we talked about the conjunction of Jupiter and Saturn while doing a bit of myth busting.

Watch it here. Or watch the video or our RASC YouTube channel.

watched a double star vid

Watched Jenham's YouTube video on double stars in a Skymax 127 Maksutov telescope. Actually he attached a DSLR to the folded telescope, atop an EQ mount, and showed use the live view images and then still shots. Nicely done.

Wednesday, December 16, 2020

let's talk about alignments

Be careful of the articles you read about the alignment of planets and other solar system bodies. Journalists with little or no scientific background might casually use terms which have astronomical import.

I've made some infographics to explain all the interesting celestial alignments. We're viewing the planets of the solar system from above the Sun. Note that the orbits are not scale and were drawn as perfect circles. Note the planet sizes and the central star are not to scale. Not even close.

UPDATED! I replaced the infographic for inferior and superior conjunctions...


A planetary opposition occurs when an "outer" planet is opposite the Earth from the Sun. A line could be drawn from the Sun, through the Earth, and onward to the planet in question. An Earth sandwich.

infographic - opposition

Outer planets refer to Mars, Jupiter, and beyond, of course. All this can apply to minor planets, dwarf planets, asteroids, comets, etc. 

Oppositions are significant because the Earth is as close as it can get to the outer planet, at least in terms of celestial alignment. A notable special case is Mars where it follows a highly elliptical orbit making some oppositions much better than others.

In general, an opposition with a distant outer planet, Jupiter and beyond, happens about every year. That's because our planet zips around the Sun faster. The outer planets moving slower you can think of as being in nearly the same position one year later. For Jupiter, it's actually close to 400 days. Mars? 780 days! Mars is movin' fast and it takes a while to catch up! Beep beep.

If you substitute the Moon for the red planet position above and the alignments are perfect in three dimensions, the Earth will block some of the sunlight reaching the Moon. This we refer to as a lunar eclipse. Curiously, no one refers to the circumstance as "the Moon is at opposition."

solar conjunction

When a planet is on the opposite side of the Sun from the Earth, with the Sun in the middle, we call this a conjunction. Specifically, a solar conjunction. 

infographic - conjunction with Sun

Personally, I don't get excited about these events. I don't add the particulars to my astronomy planning calendar. Partly because there is nothing to see.

Given the small planet could be behind the large Sun, the Sun would literally block the view from Earth. But the more immediate consideration is that the planet, even when not perfectly aligned with the Sun, is extremely close to the Sun. When the Sun up in our daytime sky, there's no way to see the planet given the bright blue sky and the intense glare of our star. 

In fact, there's a danger element here. Do not attempt to view planets near to the Sun, before, during, or after conjunction. Certainly do not use magnification, i.e. binoculars or telescope. The risk of damaging your eyes is too great.

All that said, the "moment" of conjunction with the Sun is significant astronomically even though we cannot directly observe it. It means that the planet which was in the evening sky a short while ago is now transitioning to the morning sky.

Again a solar conjunction is a moment in time and we can take two things away from these events:

  1. the planet is currently not visible
  2. it will show up though, soon, in the morning sky...
We explicitly refer to outer planets here. And the alignment with the Sun is referred to simply as a conjunction. There are special cases though for the "inner" planets.

inferior and superior solar conjunction

The "inner" planets will periodically align with the Sun as viewed from the Earth. Actually, it will happen two times during each inner planet's orbit...

infographic - inferior and superior conjunctions

The inner planets refer to Mercury and Venus, both closer to the Sun than the Earth.

The illustration shows the tan planet between the Earth and the Sun. This is referred to as inferior conjunction or inferior solar conjunction.

The beige planet is on the other side of the Sun but still lined up with the Earth. When an inner planet is on the far side of the Sun from the Earth, we call this superior conjunction. [ed: Graphic updated.]

Like in the previous scenario, an inner planet on the far side of the Sun will be invisible due to bright, dangerous glare of the Sun.

If someone says the inner planet is "opposite" the Sun, that choice of wording might be misconstrued as "opposition." That's why I've been trying to avoid the usage.

Now something neat can happen when an inner planet is at inferior conjunction and everything is aligning perfectly: you can get a solar transit.

Transits of Mercury are somewhat common but difficult to observe as Mercury is so small. I observed and imaged the 2016 May 9 event. The last one occurred on 2019 Nov 11. I watched it on the internet. The next is 2049 May 7.

Transits of Venus are rare. The last one was 2012 Jun 5. I was fortunate and viewed and imaged it. A really fun day.

It should go without saying that solar transits are dangerous to observe. You must use proper filters for your eyes, camera lenses, binoculars, and telescope.

One more thought experiment. If you swap the Moon for the tan planet in the diagram above, put the Moon between the Sun and the Earth, and the alignment in 3D space is perfect, you get a solar eclipse

Then there's the sub-types of solar eclipses: partial, annular, and total. Some argue a total solar eclipse, where the Sun is completely blocked by the Moon, should be called an occultation.

An occultation is was one object blocks the view of another. The most common usage of this is when an asteroid occults a star or the Moon occults another celestial object, say a planet or a double star.


An appulse describes when two celestial objects are relatively close to one another from our perspective on the Earth.

infographic - appulse

The diagram above shows that the red planet is a bit to the right of the beige one. While they are not perfectly aligned, and not technically in conjunction, they may well be attractively close in the sky. That often makes for good photo opportunities.

I do not know if there's a strict definition of an appulse which specifies how close the objects need to be to one another. It seems that people perk up when objects are with 5 or 6 degrees, which is the approximately field of view for binoculars. When objects get to about 1 degree in separation, that means they are possibly viewed in a telescope at low power. Less than a degree? Every one loses their mind.

planetary conjunction

A conjunction of planets may occur when two planets line up well as viewed from the third rock from the Sun.

infographic - planetary conjunction

A planetary conjunction can occur with inner and outer planets. 

Venus-Jupiter conjunctions are arguably the easiest to observe with the naked eye as they are normally the two brightest planets in the sky.

Jupiter-Saturn conjunctions happen about every 20 years. Given Saturn moves 1/3rd of it's orbit in that time, the two planets will appear in different parts of the sky. That means sometimes the Sun will be in the way.

Technically, a conjunction in astronomy has a very strict definition. The objects are at the same Right Ascension or longitude along that ecliptic.

Again, you can get occultations happening where a large foreground object blocks or hides the background distant object. This can happen with planets, the Moon, and even moons of planets. But you need that perfect alignment in all three dimensions.

Hope all this helps.

See the RASC Observer's Handbook for more information on alignments, dates of oppositions and conjunctions, lunar and solar eclipses, and various occultations.


There are other alignments or arrangements that astronomers may refer to from time to time (e.g. quadranture) but I've highlighted key ones relevant now...

finally read a good teaser

Well! Look at that. A smart, respectful, appropriate, calm, factual teaser about the upcoming conjunction provided by the Sudbury news website.

Not sensational. Not outlandish.

a good teaser on the conjunction

I like the use of the word converge. The embedded location: "western sky." And the caution: "low." All without inflating it with untoward, meaningless significance. Plus an excellent photo!

Well done!


Photo by Gary Boyle, RASC member in Ottawa.

Tuesday, December 15, 2020

listened to Stürtzer

I am listening to Martin Stürtzer's album entitled Far Beyond The Stars tonight. Nice ambient music to write and work by. The song titles are all thematically appropriate such as Hydra, Pleiades, Third Planet, Jupiter Cyclone, and Pulsar.

tried to see the planets

Scuppered. Around 2:30 PM or so, it was looking like it was going to be clear at sunset. So I put the OTA outside to cool. I was keen to have a look at the planets in the C8—they should fit now, with the baader. I wanted to show Rhonda. A historic view. I could verify a good position for the mount in the yard. And do a quick camera test. But it was not to be. A front slowly shifted northward, crabbing over Bradford. Boo.

turned off the air

All visible. Did you know all the planets are visible right now?

To be clear, around 2 to 3 PM Eastern time, all the official planets are above the horizon, as viewed from Southwestern Ontario. Of course, the Sun turns our atmosphere blue so we can't see anything in outer space. But with Stellarium, I clicked the switch and turned the air off.

planets across the sky

Uranus, Mars, Neptune, Saturn, Jupiter, Mercury, and Venus.

Comet 11P is in the mix, not far from Mars.

Asteroids, minor planets, dwarf planets—I don't know what they're called now—are to the south, Ceres and Pallas.

Speaking of things not considered planets: Pluto is out there too, to the right of Saturn and Jupiter if I remember correctly... The Moon. Yuck.

Comet 141P is between Neptune and the gas giants.

Saturn and Jupiter are heading toward the amazing conjunction so appear, in this image, merged.

Mercury is awfully close the our star.

Venus is setting.

Monday, December 14, 2020

viewed Jupiter and Saturn (Bradford)

I popped outside as it seemed it was clear, according to the weather tools. Fifty percent cloudy to the north but surprisingly clear to the south. Jupiter was obvious. Startled the bunnies as I headed half-way down the yard. Ho ho, it fits in the notch. That was a good sign. Got it, spotted Saturn up and left, about a 45 degree angle, a pinkie fingernail away! Yes.

Sunday, December 13, 2020

received the first 2021 SkyNews

Received the latest SkyNews magazine today.
cover of the Jan/Feb SkyNews magazine

Looks like this issue is looking ahead to 2021 with a listing of the top 10 events.

Writings by Chris and Nicole. He talks about advanced deep sky campaigns; she talks about telescope shopping.

Nice cover. Too bad about the huge white address label box on my edition... Ugh.

I'm not in this issue but I'll return in the next.


Correction! One of my photos was featured! The Hubble Variable Nebula shot with BGO. I forgot... Page 21 for Chris's article on challenging deep sky objects.


See the online snippets for more info.

comparing meteors to stars

Noted a great remark by Phil Plait on his redux article in the Geminid meteor shower.

Meteors are generally not terribly bright.  A few can be blazing, but most are about as bright as your average star...

Well put. I often encourage people to view meteor showers from a dark site.

Plait's helpful statement underlines that if you can only see magnitude 2 or 3 stars from your home location in the city, then you're not going to see many meteors. 

I think that we're trying to say is that the average meteor is similar in brightness to mag 4 or 5 stars... So use that as your threshold for assessing your local light pollution.

Saturday, December 12, 2020

enjoyed Bate's videos

I stumbled across a great YouTube video by Professor Matthew Bate from the University of Exeter in the UK. It's about the December 2020 conjunction of Jupiter and Saturn.

Then I found a second one. He returns to talk about past conjunctions on the 400 year cycle as well as "triples."

They are both amazing. Informative, explained with clarity, backed by solid maths.

proofed a RASC TC video

Reviewed Arushi's video for Andrew. She is a young member of the Royal Astronomical Society of Canada - Toronto Centre. Her impassioned presentation on pursuing the RASC Explore the Universe certificate is a joy to watch.

See her first solo presentation on the RASC Toronto Centre YouTube channel.


shared conjunction stuff

My cousin's husband Blaine texted me a few days ago. Haven't seen him for a year. Was surprised to learn his interest in astronomy then...

If you capture any cool pics of the Jupiter Saturn dance, please share.  My plan was to buy my first real telescope last summer.  COVID kind of changed those plans.

Yesterday I replied, apologising for the delay. I shared my wide-field shot from 2 Dec, told him my plans to shoot prime focus. I also shared my quick info video.

He thanked me for the links.

I'm going to send down to my brother in South Carolina too.  He's been keeping an eye on this too.  I'm going to have some questions for you again this spring.  I want to buy a telescope and was hoping [for] a little guidance in that purchase.

Glad to help.

Wednesday, December 09, 2020

too cloudy

Popped outside again looking for aurora. Clouds. Again.

helped at last RAN

Rushed from work into the RASC Toronto Centre Recreational Astronomy Night meeting. Brutal commute! ;-) Tech issues (probably due to bad Rogers service) mucked up our live stream. Aside from that it went well behind the scenes. I was backstage, as general help. I was the questioner for the presenters.


Raw video recording available on YouTube. It's glitchy...

Pilot article corrected

I noted a sensational article on a couple of days ago. Lots of problems, ambiguity, some mistakes. No ability to comment or rebut.

But then I spotted that this was a repost. The original was on the Virginian Pilot web site, written by Joanne Kimberlin. Her phone and email was included with the article!

I reached out on Dec 8. I shared that I had identified some technical mistakes in Jup-Sat article. The main issue I commented on was her statement that "it’s been nearly 800 years — we’re talking Middle Ages — since they got this close."

The statement was wrong about the 800 years. I provided the separation values for 1226 and 1623 compared to this year and commented on the visibility. I suggested different wording like "... it’s been about 400 years since they got this close."

When Ms Kimberlin replied a short time later I was astonished. She thanked me and explained how she and her university planetarium director had arrived at the dates. She wondered if it was in the exact wording - as in "visible in the night sky." Bingo. She said she would investigate the matter and thanked me again. Huh.

I thanked her for the quick response. Then I raised the matter of the 2080 event. I explained it would be very good but in a mere 20 years, the next conjunction would be very impressive. It sounded like we were on the same page about the dangers of writing quickly and the importance of helping people understand astronomical phenomena with clarity.

That said, I was not feeling terribly hopeful. So it amazed to receive a follow-up a day later.

I've spoken with local planetarium director who says, yep, they were one arc minute closer in 1623 but not visible to the naked eye - so the devil is, as usual, in the details.  I've written a correction for tomorrow's paper and tweaked/corrected the story online.  Planning to address it again in a Dec. 20 reminder story.  Thank you for pointing out the error, though.  I really do hate it when we get things wrong.

Very impressive. Good to see some news media people caring about their content.

I refer to the corrected article online at The Pilot. It's still emblazoned with the 800 years phrase in the title but the close conjunction in 1623 is noted per the "For The Record" footnote.

Tuesday, December 08, 2020

double checked 20 years from now

I'm not crazy.

I checked in SkyTools...

Jupiter, Saturn, Mercury, Spica, and the Moon 20 years from now

Snapshot from SkyTools 4 Visual Professional. The orange circle is a binocular view. The time is circa 7:00 AM. You can see Jupiter is about 9 degrees above the horizon.

There's the view on the morning of 2 Nov 2040 from Toronto.

I'd say that's gonna be a pretty spectacular conjunction!

20 years from now... Hello!

checked a log page

Richard W sent over his log sheet for 66 Ceti. What a treat. It's exciting, fulfilling? I'm not finding the right word. It's deeply satisfying seeing people start to work on the RASC double star observing program.

I closely examined his information and sketch as he sounded a little unclear about the target. He also noted he hadn't see the third star as shown in Stellarium. I checked my log notes, SkyTools, and Stellarium which revealed a catalogue error in Stellarium: some random faint star beside the A and B stars. I explained he had been caught in the cross-fire.

We also talked about cardinal point markings for sketches. I give some tips for temporarily turning off the sidereal tracking for his mount.

another sensational article

Maybe I should not follow this referrals as the Google skynet bot AI keeps sending them to me...

Spotted the headline In their closest alignment in 800 years, Jupiter and Saturn will create a wonder: A Christmas Star.

Oh boy. 

Published on 7 Dec by No comments feature available, no direct connection to the author. No easy way to comment or correct.

I've seen a few headlines from of late that I would describe as sensational or flamboyant. I tried to learn about this site. It says it is "powered by Science X Network." They go on to say "Science X™ is a leading web-based science, research and technology news service which covers a full range of topics." So a news service.

Wikipedia has this to say: " is a UK-based science, research and technology news aggregator offering briefs." Ah. They collate information from press releases, news agencies, and journal reports. They also produce their own science journalism. OK, that sounds good overall.

Some where along the way I noticed the article actually came from other site. Clearly this Jupiter-Saturn article was relayed via the aggregator process.

A Google search with the word "reliable" showed this at the top of the results.

"Overall, we rate a credible Pro-Science source based on the publication of scientific information from credible universities and peer-reviewed publications as well as properly sourced original content." That is from, whoever they are.

The wikipedia article had an interesting reference to Ars Technica piece by John Timmer from a few years ago but that seems timely. It is entitled PR or science journalism? It's getting harder to tell. They point out that many establishments have shut down their science departments and have asked journalists with no science experience to fill in. In the mix are private organisations wanting exclusive access, i.e. a slice of the action.

So, as Katrina says, question everything...

Monday, December 07, 2020

views in the telescopes

It occurred to me little MCT might show Jupiter and Saturn before the big 'scope. Fired up SkyTools and configured an eyepiece view for the Meade ETX-90 with the Celestron 26mm.

view in ETX-90

Then I set it to the Celestron 8 with the baader 36mm.

view in C8

I was a little surprised but it makes sense. The wide view baader ocular will show more sky.

In addition, of course, the C8 has better light grasp. So more stars.


Sorry, forgot to include the date data: 10 Dec at 5:00 PM EST.


My new editor contacted me this morning to remind me of the deadline. What deadline? Immediately she sent a follow-up realising she had changed her timeline but not let me know. Good thing I got a jump on my research... I was able to throw together a first draft quickly.

Sunday, December 06, 2020

noted some glaring errors

An article by meteorologist/science writer Scott Sutherland on The Weather Network caught my eye.

The title: Start off your winter with the greatest Great Conjunction in nearly 800 years.

You know, I appreciate articles on astronomical events. Let's get more people into astronomy. But don't distort things and please get your facts right.

Oh boy. I thought that headline a little bit sensational so I read the entire article. Some of the content is good but it also contains errors or ambiguous or convoluted explanations. Time for myth-busting. Here we go.

headline hoopla

I've a minor issue with the headline. I think that banner might be over-hyping the event. That said, the 800 year reference is clarified within the article. Still, I think 400 years would be fair. The historical references are important, don't get me wrong. Why not just emphasise the 20 year cycle?

How about a headline: Check out the cool conjunction of Jupiter and Saturn this winter.

quick list issues

Near the top of the article is a "quick list" highlighting interesting events. It's pretty good overall. But the author notes to Jan 24 for the "Alignment of Earth, Sun and Saturn." And then the 29th for Jupiter.

What he does not say is that there are "conjunction" events where Saturn is in conjunction with the Sun and 5 days later Jupiter is in conjunction with the Sun. Personally, I consider solar conjunctions as non-events. A thrust of this article is stuff you can see and enjoy. Solar conjunctions? There's nothing to see.

The planet is question is behind or beyond the Sun. In some cases, truly behind it, directly, such that you couldn't possibly see it. If the planet is inclined above or below the Sun, theortically it could be viewed, as nothing is blocking it. But the problem is that the Sun is right beside the planet and viewing the planet would be extremely difficult in a brilliant sky. More importantly, it is extremely dangerous.

My point is, Jan 24 and Jan 29 are moments when you know you cannot see Saturn or Jupiter. If somebody said to me, "Can we view Saturn in your telescope?" I'd say, "No, unfortunately, it's behind the Sun or very close to the Sun. It's the wrong time to look at this planet."

It is significant astronomically in another way: it tells us that the planet is transitioning from the evening to the morning sky. Astronomers know they cannot view it but they also know where to start looking for it in a few weeks or months...

So, while there's a big section on conjunctions and alignments in this article, none of this is clearly explained, sadly.

winter air

OK. I might be on thin ice on this matter...

Sutherland says that "stars, planets and the Moon appear crisper and cleaner" in the winter. Now, this is interesting because we have a weather expert, a professional meteorologist commenting on this but I really do not think this is an entirely fair comparison. 

He says the humidity is lower in the winter. Really? I pulled up some historical data for Toronto, Ontario and it seems the average humidity varies between high-70% and high-90% with an overall average of 81%. Most importantly, September was the most humid month whereas May was the least. January and February were below 80 with a sharp drop in March. Curiously, since he's alluding to the official start of winter... 

Geography is going to be a big factor, of course, so looking at one city is not appropriate. But I struggle with his remark that the "air overhead tends to be drier." Drier in the winter? Not by much. OK. Let's leave that as arguable or contested. 

In the same sentence, he says the air is "more stable." This I really have a problem with. Astronomers, of course, use more complex or distinct measures, notably transparency and "seeing." The seeing or steadiness of the air is important for planetary and double star observing and imaging. And I believe astronomers widely argue that seeing conditions are best in the "shoulder" seasons, spring and autumn. I think the jet-stream is a major factor affecting seeing and of course that is constantly in flux. A weather expert commenting on stability should be very conversant with atmospheric seeing. Ironically, a Canadian meteorologist should be extremely familiar with it as it is a very unique product of Environment Canada.

Back a bit, to a point within that previous paragraph. Given that Canadians live across a broad range of latitudes, one's geographic location becomes a significant factor. The jet-stream effect for your location will drive the seeing conditions. I would hope a meteorologist would be cautious about local weather effects.

I believe our author is caught up in some mythology and has not done proper research. Astronomers would not universally say that the air overhead is better or more stable in the winter. In fact, I suspect many will argue it is worse. This may be anecdotal but a good number of astronomers use and quote Clear Sky Charts which is based on Environment Canada weather data! And many astronomers, pro and amateur, have Sky Quality Meters so actively measure and assess the sky. We're good at it!

I also think the author is caught up in the "stars are brighter in the winter" not considering the Sirius is in fact the number one brightest star in the night sky, a star visible in winter time! It's not a better sky; it's a very bright star. There are lots of bright stars in the winter constellations. That does not equate to better viewing. Personally, I often note significant twinkling or scintillation of stars in the winter. i.e. bad seeing.

In the end, I believe astronomers often say that winter offers poor seeing but good transparency whereas the summer can make for good seeing and less than ideal transparency.

Also, astronomers know or learn that the worst seeing is usually when the transparency is best—right after a cold front has come through. Something a meteorologist would fully appreciate. While there are always exceptions, the coldest, windiest nights usually have bad seeing.

Finally, the "darker" nights I also think could be clarified as it has to do with astronomical twilight. The winter skies may seem darker perhaps because they are longer. There is a longer period of time between astronomical twilight starting after sunset and ending before sunrise. In general, astro-twilight is about one hour from the set-rise time. In south-western Ontario, at the summer solstice, June 20 or 21, total darkness can only be about 3 hours. Travel north, that time reduces. Far enough north, of course, the sky does not get fully dark. So, again, one's observing location is a big factor. I think our author is based in south-western Ontario, at the lowest latitude in Canada.

alignment cycles

The author says:

As Earth, Jupiter, and Saturn orbit the Sun, roughly every 20 years, the timing works out to bring the two bright gas giant planets into alignment in our sky.

This is a mistake, arguably rather significant. 

Jupiter orbits every 9 years; Saturn about 29. I'm assuming everyone knows the orbital period for their home planet. Sorry, a bit facetious of me. 

Given Jupiter's faster inner track, it "catches" Saturn about every 20 years. That's the resonance of the Jupiter-Saturn crossings. Sutherland does toss out that later elsewhere in the article. Regardless, the wording of the aforementioned paragraph is wrong and hopefully will give any reader pause.

Running simulations in Stellarium, I checked the other numbers (some of which the author did not share) for the Jupiter-Saturn "great conjunctions."

date separation
the Sun
4 Mar 1226 2' 49°
16 Jul 1623 5' 12°
21 Dec 2020 6' 30°

where ' = arc-minutes.

He suggests the 1623 conjunction couldn't been seen. Perhaps. Certainly, they were close to the Sun. But it might have been handy to mention Galilei beginning to use a telescope 'round that time.


When Sutherland tries to help people know where to look, he says "Jupiter and Saturn are nearly on the other side of the Sun from Earth on December 21."


I think he's referring to the planets being on the far side of the solar system. And this speaks to the quick list matter with the alignment of Saturn and Jupiter. But it's all poorly worded. One could take the sentence above to reference opposition events. He does talk about opposition events at other times in the piece and does say this happened in the summer. Good. But again, I have a feeling he's referring to the solar conjunction events. But even then, they do not happen on December 21! That's over 1 month later...

He goes on, "Thus, they will be very close to the horizon after sunset."

I think he's trying to explain where the planets are in the solar system. There are diagrams in the article but they are very small. It's a good effort but muddled.

For this section, he'd be better off just saying, "Jupiter and Saturn are left of the Sun, about 30 degrees away, on December 21." There. Done. Clear and indicates where to look.

While I'm wired this way, I think explain where bodies are in the solar system is going to be challenging, particularly for audience members who might have some trouble with three dimensional viewpoints for an observing point high above the solar system. It's admirable to try to explain it but one most be spot-on with terms and the visuals should very easy to interpret.

Also, he talks about about having a clear view. 

This means a tall building or another high vantage point, or a wide-open field, with nothing obscuring the horizon.

He should say, "This means getting to the top of a tall building..." You do not want a tall building in your way obviously.

That's just a minor grammar issue.

next event

When Sutherland mentions the next occurrence, he says:

It's definitely worth making plans to see this event if you can.  We won't see another one like it for another 60 years.

Wrong. Again, these Jupiter-Saturn events happen roughly every 20 years. During the next event, Jupiter and Saturn will be just over 1 degree apart. That will still fit in a low power telescopic view. It will still be awesome to the eye, in photos, and in binoculars. Also the Moon will be attractively close! Mercury will be in the mix too! This will occur in the morning, around 7 AM-ish for Ontario residents, on 2 November 2040. The planets will be 25 degrees from the Sun (to the right).

That's actually gonna be an amazing event (if you're a morning person; if it's clear)!

Now, some appulses will be better than others.

I think he says "like it" meaning so close but if you're trying to genuinely increase knowledge of interesting astronomical phenomena (and not sell website ads), you should list the dates of the next couple, and make reference to the distance from the Sun. 

The facts are: super-tight conjunctions are rare, yes. But conjunctions of these two planets do not happen once every 800 years... That's my issue with this whole piece, really. 

Sutherland includes an image with a telescopic view but did not reference the orientation or inversion or flipping. Nor is there a specific time indicator. That's a big deal for people trying to identify moons.

At this point the discussion on the "great conjunction" concludes. The article continues delving into other astronomical events... There are more problems.


I believe Sutherland's words for the perihelion topic are fair but I was disappointed to not see a stronger stance and more facts. 

For example, the furthest distance was not quoted. That would emphasise that the Earth is 1 million km closer to the Sun this time of year. I love sharing that fact with people.

More importantly, I feel this is a key opportunity to do some myth-busting. While we're closer to our star, it's winter in the northern hemisphere. That will strike some people are odd. Then a meteorologist/science writer could explain/remind that seasons are determined by the axial tilt of the planet, not the Earth-Sun distance.

conjunction function

In the CONJUNCTIONS AND ALIGNMENTS section, readers are told that events like the upcoming Jupiter-Saturn clustering "astronomers refer to... as conjunctions."

There's a subtle terminology issue here. Technically, when objects are close together it is an "appulse." Scientists will use appulse for celestial objects being close together in any orientation. You need a specific event or circumstance for a conjunction. The technical term conjunction means that the objects have the same right ascension (RA) value or have the same longitude value along the ecliptic.

As previously mentioned, Sutherland really muddies the waters with conjunctions of the planets themselves and the Sun. They're all conjunctions, generally, but solar conjunctions are a subclass. And he mucked things up with oppositions too. The whole alignment section was an opportunity to clarify the interesting alignments that happen in the solar system.

If he wanted to do this right, some good diagrams would help. He should have top-down diagrams for planetary opposition events, solar conjunctions. He should avoid getting into inferior and superior conjunction events with the inner planets in the interest of brevity.

the faint pyramid

I was heartened to see that Scott Sutherland referred to the RASC and the Observer's Handbook and Roy Bishop's article on zodiacal light. And Sutherland does caution the reader that that light pollution can spoil the view. But I think it is fair to say that extremely dark skies are required, nah, mandatory. He might give city dwellers the impression they can see this. Nope. It is very faint. You're going to have to drive out of town for this one. Or check it while at the cottage. 

Also, I don't like the suggestion to "look to the western horizon." It will appear, if at all, in the south-western horizon. Be precise. This might sound like nit-picking but if there's a town due west, observers will mistake that light pollution as zodiacal light.

If I may be so bold, this is a target for an advanced astronomer. Not to sound exclusive. What I mean is: this is a challenge target for an accomplished astronomer. It was years before I saw it (in the country). Good luck but you're gonna have to work at it. Or shoot a long exposure. And don't get tricked by the light dome or a distant town or city.

The most amusing thing here is the photo. Um, that's taken from a mountain top from a remote observatory location!


I feel strongly (obviously) about this. News writers should do their due diligence and proper research. Writers providing science information are compelled to get their facts right, clarify, and illuminate. And if you don't know, reach out. Get a technical editor.

I filled out the Contact Us form again on the Weather Network website.

When I did this before, they never responded to me, while it is hinted that they will, though they receive a lot of responses.

I doubt I'll hear anything about this article.

I wanted to fact-check and correct and clarify.