Sunday, July 12, 2020

check out the Skylights

Check out my buddy Chris's Skylights for this week. In addition to all his general what's up astronomy info, he has lots of info on the comet... Of course, Jupiter and Saturn are pretty amazing right now.

reviewed article, late

Proofread my Journal article... Down to the wire.

created a new plot

Comet C/2020 F3 is transitioning to the evening sky... soon. It is officially in Lynx now.

comet path for the next few days

You can see it's climbing. Normally a celestial object higher is easier to see.

And the comet is drawing closer to the Earth. Perihelion was on 3 July. Perigee is coming up soon. Wikipedia says, the "closest approach to Earth will occur July 23, 2020, at a distance of 0.69 AU (103 million km)."

But the comet is moving away from the Sun. So, it will be fading.

Hopefully, we'll experience a nice balancing effect...

good sources

Need more information on comets with visibility assessments? I regularly use Yoshida's aerith site and Crinklaw's comet chasing page.

Want to submit your observations, head over to COBS. This one is new to me.

Also, aerith and COBS have magnitude charts... Happy hunting!

where is C/2020 F3 now?

If you want official and detailed information for the C/2020 F3 (NEOWISE) comet, check out the SSD page by NASA. This is the Solar System Dynamics web site by the Jet Propulsion Laboratory.

C/2020 F3 path through inner solar system

A great feature of this site is the ability to show a 3D orbit diagram that you can pan and tilt.

Wednesday, July 08, 2020

made a comet video

Andrew thought we should help people with their comet questions so suggested Chris and I make a video. We quickly discussed what we should cover, while trying to keep it short and zippy, and put together a script. Watch it here. About 35 minutes.

Video produced by Betty and Andrew on the RASC Toronto YouTube channel. Hopefully the first of a series...

Tuesday, July 07, 2020

enjoyed the morning show (Bradford)

We headed to the water reservoir for 4:00 AM, taking in a bunch of planets to the south, Jupiter, Saturn, and Mars, with the Moon in between.

Venus was rising, orange-tinted. There were low clouds in the north-east and we wondered if they would scuttle our efforts. I blindly shot and found the comet, C/2020 F3 (NEOWISE) just above the cloud band. Yes!

Viewed it in the binoculars (cheapo Bushnells) and we were able to tag it naked eye (when blocking the silly bright, badly aimed street lights). Star-like core. Tail fanning upward, nearly vertical. Rhonda's first.

Canon 40D, tripod-mounted, RAW mode. Shot in tungsten white balance; corrected to daylight. Pre-processing in DPP.

comet C/2020 F3 over Bradford

4:18. Wide-field, 18-55 Canon kit lens at 18, ISO 1000, f/8, 30 seconds, auto-focused (then set to manual), 10 second timer. Dark-subtracted with GIMP.

Auriga, the comet, Venus. [ed: I was thrilled to discover the Pleiades in the shot! Did not know at the time it was included.]

Stoopid light pollution!

4:28. Rhonda saw it directly, I caught it out of the corner of my eye, and flicked over to see the end. A bright, fast, short meteor burnt up north-bound (an Aquarid). It left a smoke trail that persisted for many seconds. Freebie!

comet C/2020 F3 in the dawn sky

4:51. Long lens, Vivitar Series 1 zoom at about 100mm, f/16, 2 seconds, manually focused, 2 second timer.

Sunday, July 05, 2020

found the triangle (Bradford)

It occurred to me that the Moon would be between Jupiter and Saturn tonight. The planetarium app confirmed that. Oh. A near triangle, with the Moon below the ecliptic.

Jupiter and the Moon started poking through the big tree in the south-east corner of the yard but the ringed planet we could not tagged.

Out on the street, we were able to take in all three. A nearly perfect isosceles triangle.

All were very orange.

lights in the sky (Bradford)

From the porch we watched the sky darken, saw the bat start its orbits, warded off persistent mosquitoes, and watched the stars slowly appear.

Rhonda noted a bright star, high up, in the east. Vega, no doubt.

Took me a while to clue in that I was seeing the pincer stars of Scorpius, Graffias and Dschubba. Later, squinting, I think I tagged the third member, below. Antares bobbed and weaved behind the nut tree.

Once I figured out the scorpion constellation, I realised the two obvious stars to the right were of my constellation, Libra. The phone app reminded me that Zubenelgenubi is not the lucida; that trait applies to Zubenelschemali, the upper star.

Later, I could see the bottom stars of Ophiuchus.

And we were visited by an inquisitive firefly! Yeh, apropos on International Firefly Day weekend!

Saturn, Jupiter, and Moon (Bradford)

Popped outside to close up things, batten down for the night, tidy, drop the umbrella... Spotted the bright Moon. Ugh. Oh. And two planets. Jupiter and Saturn. Moon was 150% of the J-S separation, the Moon was to the west of Jupiter. It'd be really something if the Moon was actually the J-S split but I don't think that will work, this time, in the northern hemisphere.

Thursday, July 02, 2020

posted July 2020 doubles

Sent out my double star "bulletin" for July 2020. It is a short list of suggested targets. I shared this on the RASC Toronto Centre forums. And I post here for everyone.


I hope you enjoy my periodic posts with interesting and fun double stars. I think they are impressive, colourful, and beautiful. I particularly like how they punch through light pollution.

Here's a short selection from my life list. I did not include terribly tight or faint targets.

staralso known asalternate catalogue(s)
HD 106799 CamΣ1625 (Struve)SAO 2009, HIP 59836
HD 150340 HerSTF 2079 (Struve)SAO 84521, HIP 81575
1 BooSTF 1772SAO 82942, HIP 66727
HR 5568 LibH N 28 and 33 LibSAO 183040, HIP 73184
HR 6681 Ser (Cauda)HJ 2814 or HD 163336SAO 160915, HIP 87813

Please consider adding doubles to your observing list. Often they are easy. Occasionally they present some challenges and might require repeat viewing.

I look forward to hearing how you did. Holler if you have any questions.

Blake Nancarrow
astronomy at computer-ease dot com

Wednesday, July 01, 2020

cut and sanded

Once again, with Rhonda's awesome 20-inch double parallel-link arm scroll saw, I did more cuttting for the Dobsonian base project. Printed my Visio diagram for notes.

Cut the semi-circles in the box side panels. Cut the handle in the box back panel. Cut the pieces away from the ground plate to form the legs. Cut the azimuth bearing in half. Cut the various reinforcement pieces for the box and cradle.

Used the surform to do a bit of shaping.

Fired up the new random orbit sander with 80 grit and had a go at most of the cut surfaces. Spent a bunch of time on the bearings to get rid of irregularities and make them uniform.

Dob base bits

Not shown: counter-top material from Clay. Neither did I grab the wood glue bottle.

A good Canada Day project, on a lovely day.

Wow. I think I'm ready to assemble...


Hockey pucks! Still need 3 of those!

It did occur to me that i'm not sure I picked up enough furniture glides. I bought a 4-pack and that will serve the altitude bearings. But I need three more for the base-ground plate.

And I also need to figure out the box-ground plate bearing.

Tuesday, June 30, 2020

spotted Canadian content

A Google alert directed me to an article at Vice magazine entitled How to Take Stunning Pictures of Space at Home. Apropos given the new normal. Certainly I've been enjoying some more astronomy from the backyard. As I read the article, I noted some people I know and have actually met, including Dr Parshati Patel. She actually took some lovely photos from my old stompin' grounds near and around St Thomas. Cool!

Monday, June 29, 2020

noted Stellarium 0.20.2 shortcuts

Performed testing with Stellarium 0.20.2 on Windows 10.

This is an update of my keyboard and mouse shortcuts listing. This reference is for Windows and Macintosh computers.

The "notes" column to the far right with numbers are keyed to the footnotes. For example, 1 is used to indicate newly added or recently changed items.

controlling the surroundings


show Location window


Fn F6


toggle cardinal compass points




toggle ground and buildings



toggle ground fog



toggle atmosphere or air



toggle sky glow/building lights

Shift g

Shift g

ground (mountain) labels

Ctrl Shift g

⌘ Shift g

return to "home" (start-up) view

Ctrl h



controlling the sky - deep sky

toggle stars



toggle star labels

Alt s

Option s

toggle constellation lines



toggle constellation boundaries



toggle constellation labels



toggle constellation artwork



toggle asterism lines

Alt a

Option a

toggle asterism labels

Alt v

Option v

toggle ray helpers

Alt r

Option r

toggle DSO/nebula labels

n or d

n or d

nebula background images



toggle quasars

Ctrl Alt q

⌘ Option q

3, 5

toggle zodiacal light

Ctrl Shift z

⌘ Shift z

toggle Milky Way



toggle digital sky survey

Ctrl Alt d

⌘ Option d


exoplanet labels, indicators

Ctrl Alt e

⌘ Option e


show Sky and Viewing Options


Fn F4

single constellation mode

remove previous constellations




show all constellations

Alt w

Option w


the sky - solar system

toggle planets and Moon



toggle planet and Moon labels

Alt p

Option p

toggle planet markers

Ctrl p

⌘ p

toggle planet orbits



toggle star-lore planet names

Ctrl Shift n

⌘ Shift n

toggle planet trails

Shift t

Shift t

toggle planet surface labels

Alt n

Option n


toggle meteor radiants

Ctrl Shift m

⌘ Shift m

toggle meteor radiant labels

Shift m

Shift m

controlling lines

toggle altitude/azimuth grid



toggle equatorial grid



toggle ecliptic line

, (comma)


toggle celestial equator

. (period)


toggle meridian line



toggle horizon line



changing image presentation

flip horizontally

Ctrl Shift h

⌘ Shift h

flip vertically

Ctrl Shift v

⌘ Shift v

equatorial or azimuthal mode

Ctrl m

⌘ m

look to east (or n, w, s)

Shift e

Shift e

look up to zenith

Shift z

Shift z

look to NCP

Alt Shift n

Option Shift n

look to SCP

Alt Shift s

Option Shift s


zoom in

PgUp or

Ctrl Up Arrow

Fn Up Arrow

zoom out

PgDn or

Ctrl Dn Arrow

Fn Down Arrow

zoom in or out slowly

Shift with keys

Shift with keys

quickly zoom in/out

mouse wheel

mouse wheel

zoom close to selected object

/ (slash)


zoom out fully

\ (backslash)


zoom very close to planet

/ twice

/ twice

set field of view (FOV) to 180°

Ctrl Alt 1


set FOV to 90°

Ctrl Alt 2


... through ...



set FOV to 2°

Ctrl Alt 8


set to 1°

Ctrl Alt 9


to ½°

Ctrl Alt 0



quickly pan celestial sphere



pan right

Right Arrow

Right Arrow

pan left

Left Arrow

Left Arrow

pan up

Up Arrow

Up Arrow

pan down

Down Arrow

Down Arrow

pan a small amount

Shift Arrow-key 

Shift Arrow-key

controlling time flow

set date/time to now



set time rate to zero



increase time flow

l (lower case L)


decrease time flow



run time at normal rate



increase time flow a little

Shift l (that's L)

Shift l

decrease time flow a little

Shift j

Shift j

drag for time

Ctrl drag

Control drag


flip time direction

0 (zero)

0 (zero)


time with mouse wheel

increase/decrease by minutes


increase/decrease by hours

Ctrl Shift

⌘ Shift

increase/decrease by days

Ctrl Alt

⌘ Option

increase/decrease by years

Ctrl Alt Shift


controlling "regular" time

show date/time window


Fn F5

forward 1 hour solar

Ctrl = (equal)

⌘ =

backward 1 hour

Ctrl - (hyphen)

⌘ -

forward 1 day solar

= (equal)


backward 1 day

- (hyphen)


forward 1 week solar



backward 1 week



controlling sidereal time

forward 1 day sidereal

Alt = (equal)

Option =

backward 1 day

Alt - (hyphen)

Option -

forward 1 year sidereal

Ctrl Alt Shift ]

⌘ Option Shift ]

backward 1 year

Ctrl Alt Shift [

⌘ Option Shift [

working with objects

select an object



centre on selected object



toggle tracking of object



deselect object

right-click or
Ctrl Spacebar

⌘-click or 
⌘ Spacebar


display search dialogue box

Ctrl f or F3

⌘ f or Fn F3

go, i.e. travel, to a planet

Ctrl g

⌘ g

toggle angular measurement

Ctrl a

⌘ a


copy object info to clipboard

Ctrl Shift c

⌘ Shift c


add custom marker

Shift click

Shift click

remove custom marker

Shift right-click

Control Shift click

remove all custom markers

Alt Shift right-click

Opt. Ctrl. Sh. click

working with satellites


configure artificial satellites

Alt z

Option z

toggle satellite display or "hints"

Ctrl z

⌘ z

toggle satellite labels

Alt Shift z

Alt Shift z

controlling the screen

toggle night (red light) mode

Ctrl n

⌘ n

toggle full-screen mode




toggle toolbars/menus, i.e. GUI

Ctrl t

⌘ t

save screenshot to disk

Ctrl s

⌘ s

toggle planet selection marker

Ctrl Shift p

⌘ Shift p

close a window/dialogue box



controlling the application

show configuration window


Fn F2

show help/about window


Fn F1

show script console window



keyboard shortcuts window


Fn F7

show Astro. Calc. window


Fn F10

show Bookmarks window

Alt b

Option b

show Exoplanets config window

Alt e

Option e


show meteor settings window

Ctrl Alt Shift m

⌘ Option Shift m


show meteor search window

Ctrl Alt m

⌘ Option m


quit from Stellarium

Ctrl q

⌘ q


  1. Recently added or changed shortcuts.
  2. On the Mac, the shortcut ⌘ h hides the app. This is an operating system shortcut.
  3. On the Mac, the shortcut ⌘ Shift q causes Stellarium to quit. 
  4. The operation of function keys on both Windows and Mac computers may require the use of a function or Fn key.
  5. Keyboard shortcuts associated with a plug-in. They may not function if the plug-in is not active.
  6. The digital sky survey layering feature refers to the display as a "hierarchical progressive" sky survey.
  7. The "remove" constellation shortcut applies when "single constellation mode" is active, as triggered in Configuration, Tools.
  8. The F11 does not work on iMac 21.5 and 2011 wireless keyboard.
  9. Referred to as surface "nomenclature" labels. This marks detailed surface features on planets, for example, Olympus Mons on Mars.
  10. On the Mac, only works when mouse is dragged horizontally. Only changes seconds.

Some shortcuts were omitted. Notably those for the oculars plug-in. And those to do with scripting.

Finally, of course, Mac documentation and keyboard labelling is inconsistent. We note the symbols below:

⌘ (cloverleaf) is the Command key,

      with the apple symbol on very old systems

⌃ (carat) is the Control key

⌥ is the Option (alt) or alternate key

⇧ (up arrow) is the Shift key

⇪ (up arrow with segments) indicates that the Caps Lock is used

fn or Fn is the Function key

Please report errors in the comments below...


See my "top" list for a very short collection of most frequently used, most helpful, techniques. Handy if heading into a presentation.

tried Stellarium 0.20.2

Downloaded and installed Stellarium 0.20.2, the latest version, 64-bit, to the Windows laptop.

255 MB. It's not a small app anymore.

I like the camera sensor option in oculars. In particular, I like that you can see the sky surrounding the rectangle. They still mask the sky when using an ocular proper. Never liked that. The icons in the toolbar were refreshed. More consistent with the rest of the interface controls.

Had to change the celestial object information. Sometimes there's enough rows so to fill the display vertically. That's too much. Quickly set to "short" which shows but two lines. I'll need to spend some time customising 'cause something in between is practical.

Searching is enhanced. I like the Lists tab.

Sounds like they updated the user manual. Wow.

read Rod's shocking findings

I read Unk Rod (Mollise's) blog post (in June batch) about the major problem he had with his new-ish SCT telescope. Thinking grease was coming off the central shaft, he opened it up. The strange colour and pattern on the inside of the OTA was in fact the paint coming off! Wow. And apparently other users are experiencing this. A surprising mistake, which it seems the manufacturer is not owning up to. The other bizarre thing he discovered is that the applied glue to the corrector plate complicating removal. I immediately thought conspiratorial thoughts... He hammered things out (do not take that literally) thank the Universe but it is just another disappointment from Celestron.

Sunday, June 28, 2020

finished FNGC gallery

Woo! I suddenly remembered I had an image to add to my Finest NGC gallery! After adjusting for image scale, I updated the online image gallery. With my new image of the open cluster NGC 6520, I have captured every item! Very satisfying to see every RASC Finest object there.

Saturday, June 27, 2020

broke 1600

My double star count passed 1600, including the objects seen and imaged last week. That's kinda wild. The doubles attempted count now is over 1720.