Thursday, October 18, 2018

double take on Mars (Bradford)

Noted the Moon and Mars about 5° apart during the walk home from the GO station. Gibbous Moon. Mars to the right (east). In fact, it was fairly clear. Lots of stars visible.

Monday, October 15, 2018

imaged the amazing Pisces Cloud (Halifax)

It's filled with galaxies.

For fun, I commanded the BGO to aim at the Pisces Cloud, a galaxy group also known as Arp 331, centring on New General Catalogue object 383. Wow.

the centre of the Pisces Cloud galaxy group in luminanance

Luminance only, 60 seconds subexposures, 10 stacked shots. FITS Liberator, Paint. North is up; east is left.

There are so many galaxies in this shot. I can see many in my long exposure... But only a few are identified in Aladin/SIMBAD and my SkyTools 3 Pro software.

ST3P calls NGC 383 the Pisces Cloud. That's a little odd. It also shows NGC 383 may be referred to as MCG 5-3-53 or PGC 3982.

The bright elliptical galaxy north-north-west of NGC 383 is NGC 380. 380 is also known as Arp 331, MCG 5-3-51, and PGC 3969.

Due north of 383 and due east of 380 is the tiny nearly-round LEDA 1998992 galaxy.

Between 380 and 1998992 is LEDA 1999066, a small smudge. Dimmer than 1998992 but about the same size.

North of 380 is NGC 379. This looks like a canted spiral galaxy. Or maybe a lenticular. ST3P says aka Arp 331, MCG 5-3-50, and PGC 3966.

There's a flattened triangle of bright stars north of 379. Above or north of the brightest star is the elongated smudge of 2MFGC 815. SkyTools calls it LEDA 2003479.

It sure looks like there are a bunch of faint galaxies here... oriented horizontally.

West of this same triangle is a very dim shape, small. 2MASX J01065374+3234434. Also called LEDA 2003331 according to ST3P.

North-west of 383, nearby, is medium-sized oval fuzzy. That's 2MASX J01071798+3225281. ST3P calls this LEDA 197570.

Nearly due west of the 383, well away, below the tight triangle of stars is the stretched smudge of LEDA 1995971.

Between but a bit south is the edge-on spiral galaxy UGC 679. ST3P also notes this as MCG 5-3-49 and PGC 3950.

LEDA 1993906 is the small non-round blotch south-west of 679.

Further along, further south-west is another similarly sized oval: LEDA 1992085.

NGC 382 is the round small but bright galaxy near 383 to the south-south-west. ST3P: Arp 331, MCG 5-3-52, and PGC 3981.

Further out is 2MASX J01071026+3220485, a soft blob. It's to the west of the right-angle triangle of stars. Known as LEDA 1992625 in ST3P.

West of the aforementioned galaxy is a bright fuzzy, round, but still quite small: NGC 375 aka PGC 3953.

And further still is another round small elliptical: NGC 373. Or PGC 3946.

Nearly due south of NGC 383 are two more ellipticals, practically the same size, but at slightly different angles. NGC 385 (Arp 331, MCG 5-3-56, and PGC 3984) is to the north and NGC 384 (Arp 331, MCG 5-3-55, and PGC 3983) is to the south.

NGC 386 is about half the distance of 385 but slightly east. Smaller and dimmer. SkyTools also calls this Arp 331, MCG 5-3-57, and PGC 3989.

2MASX J01075199+3215217 is much further away but inline with 386. Very dim. Round. SkyTools says it is LEDA 197572.

Aladin notes 2MASX J01073307+3223282 to the south-east of NGC 383. It is dimmer than 386. Smaller. But the core is slightly dimmer. SkyTools calls this NGC 387 or PGC 3987.

NGC 388 looks like a spiral galaxy, canted at an angle, due east of 385 and 384. aka Arp 331, MCG 5-3-59, and PGC 4005.

East-north-east of 383 is NGC 390. Another galaxy disc tilted. SkyTools called this PGC 4021.

North of 390 is 2MASX J01081590+3229567. It looks like a clone of 390 but smaller and dimmer. Maybe further away. ST3P also notes LEDA 1999738.

The curving string, from north to south, of NGC 379, 380, 383, 382, 387, 386, 385, and 384, is really neat, pearls on an necklace.

Ten total NGCs in one shot. Wow.

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Wikipedia links: NGC 383 and Arp 331 (en Français).

Saturday, October 13, 2018

fluffy dark matter

Watched Dr Laura Parker's talk on the dark universe recorded at the 26 Sep RASC meeting. She's an excellent speaker. I was most impressed at her answers in the Q&A after. Parker clearly has a very deep knowledge of this incredible domain.

Chris asked an interesting question (around the 44 minute mark). He noted an inverse relationship between the luminous and dark matter in the rotational speed graphic. He asked if dark matter doesn't like regular matter or doesn't want to occupy the same space.

Parker shared that there's a good relationship with matter distribution. But at large radii the dark matter becomes more prevalent than the visible matter. And there's good physics to explain this. The regular matter collapses and sinks to the middle of the galactic region so to form the galaxy and in the process radiates energy. Meanwhile the big ball of dark matter does not collapse, in can't shrink, it cannot give off radiation, so the dark matter remains fluffy and big.

I took lots of questions from Rhonda hopefully clarifying things about dark matter and dark energy.

captured Keid (Halifax)

I was a little surprised to see a couple of emails from the BGO robot this morning. There must have been a break in the clouds. Or better conditions than predicted.

I had had a request for ο (omicron) Eridani aka Keid, the multi-star system. The SMU observatory gathered good data, after aiming at GSC 05313 00997. Looks like a lovely triple!

multi-star Keid in luminance

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

The part of the reason for imaging this system (Struve 518) was because I wanted to double-check positions. When I last viewed this target on 19 Mar '18 from the backyard, I had noted the B star in a very different position than it was noted in SkyTools 3 Professional. ST3P shows B at a position angle of 65°. At the time I thought it approx. 60° different from that, counterclockwise in my SCT, therefore an increase in the PA, perhaps 125°. It is obvious in the image above that B (and C) are to the east-south-east. That's a PA of roughly 100°. Curiously, ST3P states in the Object Information box that the AB angle is 104° as of 2002. Here's an instance where the visual chart is very different than the OI data and it threw me off back in March.

Also, SkyTools notes another pair: Aa. With a PA of 97 and separation of 77.9. But it seems, early in 2018, I did not see this companion either.

The Washington Double Star database shows the Keid is a 5-star system with the following data:

pair first last PA1 PA2 sep1 sep2
A,BC 1783 2016 108 102 89.2 83.7
AC 1987 2011 117 97 79.4 77.3
AD 1850 1998 197 38 128.3 481.4
AE 1850 1998 279 24 99.4 569.9
BC 1851 2017 160 331 3.0 8.3
BD 1922 1999 196 28 147.0 457.0
BE 1922 1999 356 16 279.5 563.7

SkyTools lists the A, B, and C stars. The D and E stars from the WDS are mag 12-13 stars well away. They are visible to the north-north-east in the image. I'm curious why the bright, closer star beyond BC is not included.

The BC, BD, and BE alternate measures are support the main entries.

plot of Keid stars for 2018

A plot, using the current or most recent positions, from my Excel mapper tool. Good correspondence to the image.

It looks like for the A-to-B data, there's been little movement. It seems the C is moving about B. SkyTools and other sources quote the B-C orbital period around 250 years.

But the D and E values are kinda crazy. I'll consider that this is not real motion but errors in the original observations.

The SkyTools Aa entry looks suspiciously like the WDS AC datum. I think therefore I should discard it.

By the way, Wikipedia says 40 Eri is a triple.

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Wikipedia link: 40 Eridani.

Wednesday, October 10, 2018

delivered BGO talk

Delivered my presentation on using the robotic Burke-Gaffney Observatory. I think the delivery went fairly well and people seemed to enjoy it.

I made a quick information page on the RASC Toronto Centre web site. Many hyperlinks are provided. I also shared a PDF download file with general information.

The rough copy of the video streamed during the evening is available on our YouTube channel. My talk starts at the 1 hour 23 minute mark and continues to 2:10.

I was very pleased to learn that Dave Lane was on the line, in the chat room, during my presentation. Keeping me honest.

I grabbed the log:

Claudio Oriani: Hi everyone
Eric Briggs: Hi Claudio
Ward LeGrow: hey Claudio
Charles Darrow: hi Claudio
WLG: that was a picture of [a Terminator robot from the James Cameron movie]... in case you were wondering. sorry.. we werent quick enough. ;)
EB: Woo @Smubgobs
EB: Nice shirt too
Astro_yyz: it's very simple to use - and very satisfying when you see the image you requested - many thanks to Dave Lane for setting it up

Dave Lane: (that would be me)
CD: I know that Dave Lane
Astro_yyz: 👏 @Dave Lane
WLG: I will have to try it out! :)
CD: I have a TESS account
WLG: thanks Dave
EB: I've used it before, but in my secret @Dunlap_Obs identity
Astro_yyz: @Ward LeGrow it's fun 😃 No frustrating imaging issues either. Just a few simple steps to get set up
EB: I think @smubgobs was offline for a while this summer because summer
WLG: sounds great!
DL: It was off line only because the #human was away on vacation. Only down when I am not within 100km in case of bad weather.
Astro_yyz: It was cool at the last GA in Calgary. I was showing it to Nicole and Cathy Carr - sent instructions/received confirmation from robot live to my phone, showed them the image later
DL: The #human is working on the Facebook issue. It's open season on app developers these days.
WLG: no doubt.
EB: How about Instagram? Facebook is a bit old-timey.
DL: Instagram, will not let app developers post images/messages! You can read/view messages but not post!!! So it is out of the question until they open up the API.
Astro_yyz: got to scoot - have a great evening all
WLG: tks. you too Katrina!
EB: @smubgobs confirmed the new supernova 2015ai at and during the RASC General Assembly in Halifax in 2015
DL: One new observer - welcome David Quinn
WLG: I will be signing up!
EB: Is the system of astronomical telegrams still relatively solid? I know the supernova naming convention has been changed to deal with the asymptotic curve
DL: ARO has been open to RASC for a while. It is a C14 [telescope].
EB: Geometric curve, maybe I should say. Anyways I think the business model for the astronomical telegrams from Harvard has been facing rapid changes due to technology.
DL: and its a C14!
Ward LeGrow: oh.. thanks. missed that. thanks!
DL: About 120 nights per year of some data. Basic [user] is 3 [jobs in the queue max.]
WLG: thanks also for that too
DL: Calibrations are done automatically. Updated periodically automatically. The subframes all exist - just not on the website.
WLG: wow.. wish you were here!
DL: Fantastic talk

Benoit Brame: Thank you !

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It was fun sharing information about BGO. I think a bunch of people will try it.

next council meeting

Tom announced that the next RASC Toronto Centre council meeting is scheduled for Thu 17 Oct up at York U. All members welcome.

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Katrina pointed out that 17 Oct is a Wednesday. Tom corrected his note: the meeting in Thu 18 Oct.

Tuesday, October 09, 2018

gauged sky darkness

It was clear so I decided to do an assessment. Medium seeing conditions. The neighbour upstairs had their porch light on illuminating some of the trees. Not truly dark in the backyard unfortunately.

Submitted my data to the Globe At Night site (record 14350).

sketch of Pegasus and the faintest stars I could see

Sketch of Great Square and Pegasus. Could see between magnitude 4.5 and 5.5. I.e. a handful more stars than the "less than" 4.5 chart. SkyTools says some of the stars I spotted are mag 4.7 and 4.8.

I also spotted Mars down low, mingling with the trees. But still bright, orange, sparkling.

I was surprised to see meteors. Three Draconids. All short and fast. The third was extremely bright, blue white in colour.

Sunday, October 07, 2018

to present on BGO

This coming Wednesday, I will be one of the speakers at the RASC Toronto Centre meeting at the Ontario Science Centre. I'll be talking about accessing and using the Burke-Gaffney Observatory robotic telescope. Check out the live stream if you cannot attend in person.

Saturday, October 06, 2018

received SkyNews Nov/Dec

cover of the Nov/Dec '18 SkyNews
I received the SkyNews magazine from November/December 2018.

Lovely photography as usual. There's a piece on shooting with a long camera lens.

The main article is on the "greatest voyage," the Apollo 8 mission to the Moon.

I am also interested in the article on Oumuamua.

I left it with Rhonda for her to read.

Friday, October 05, 2018

imaged zeta Sge (Halifax)

When the Clear Sky Alarm Clock notification arrived for the Burke-Gaffney Observatory, I was not surprised. The clear weather over Ontario last evening was due at the east coast. Average transparency but poor seeing. Still I opened up Danko's weather resource for Halifax. Later I opened the Twitter feed. Looked like the St Mary's University robot was up and running. There were some clouds but the imaging system pressed on.

I captured the multi-star system ζ (zeta) Sagittae aka AGC 11 and/or Σ2585 (aiming at TYC 01623-2382 1) . SkyTools 3 Professional shows it has 4 elements.

This request was to resolve a couple of issues with this previously logged item. My life list entry going back to 2008 appears to have a typographical error for the separation. Also I have never noted the easy D element.

zeta Sagittae in luminance

Luminance only, ½ second subexposure, 20 stacked shots. FITS Liberator, Paint.NET. North is up; east is left.

The A and C stars are obvious with bright C touching A at the 2 o'clock position or to the north-west. ST3P quotes the angular separation at 8.3" with a position angle of 310°. The D element, happily, is visible is this image. That said, it is remarkably faint when compared to A and C. It is the next brightest star well away to the west-south-west. Perhaps 10 or a dozen times the AC split distance (77.4"). ST3P says it is magnitude 11.8. zeta Sge is in a lovely field.

By the way, the B star, a rapid binary with a 23 year period, was at a calculated separation of 0.2".

I took red, green, and blue data as well, at three times the duration of the clear exposure. It will be interesting to see the results when the colour channels are applied.

First viewed this target on 5 Jul '08 quickly noting the colours. I believe when I placed the entry in my life list, I copied from the row above, and forgot to edit the separation value from 1.6 (from lambda Oph). Sissy Haas notes the split as 8.3 seconds of arc. My 10 Jul '10 observation added nothing. It is nice to tidy this up.

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Wikipedia link: zeta Sagittae.

Monday, October 01, 2018

received markup

Rhonda graciously proofread my next article for the RASC Journal.