10 replies to this topic

[The Ardent]

Below is an excerpt of my observing article about Canis Minor. In late 2020 I embarked on a months long project observing all the area within the constellation boundaries of the lesser dog constellation. I used Uranometria 2nd edition as my primary observing guide and SkySafari as a scopeside reference. I made 766 total observations, of which 291 were cataloged doubles. The rest were galaxies, open clusters, single stars, apparent stars, asterisms, star fields,  and orange/red stars. 

 

The pages of Uranometria are divided into a grid pattern of Right Ascension and Declination. Canis Minor has 219 grid areas , so to start I have 219 observations to make. All plotted doubles are observed to see if resolved. Fainter doubles not plotted are observed and checked in SkySafari. 

 

I did not know ahead of time what was visible. I observed first, asked questions later. 

 

Here's what I found. 

 

Washington Double Star Catalog Abbreviation  =  Catalog name  , # Observations

A  =  Aitken,   9
ADS =  Aitken Double Star Catalogue ,  2
AG  =  Astronomische Gesellschaft,  3
ARG  =  Argelander,   1
ARN =  Arnold,   1
Bal =  Baillaud,  137
BRT= Barton,   3
BU = Burnham,  3
DOB =  Doberck,  1
DOO = Doolittle,  1
GIC = Giclas, 1
GRV = Greaves,    2
HEI =  Heintz,  2
HJ  =  J Herschel,  27
J = Jonckheere,  30
KU  =   Kustner,  1
KUI =  Kuiper,  1
LAF =  Lafreniere,  0 
MLL=  Mitchell,  1
OL =  Olivier , 1
ROE =  Roe,  3
SCJ =  Schjellerup,  1
SKF = Skiff,  1
SLE = Soulie , 20
STF = Struve F , 21
STTA =  Struve O,  1
TDS = Tycho Double Star,  1
WDS = Washington Double Star Catalog,  7
WFC = Washington Fundamental Catalog,  1
WSI =  Washington Speckle Inferometer , 1
XMI = Miret,  5

 

The two best doubles were faint Jonckheere 44,  and then bright Eta Cmi (BU 21) 

 

Observing site and equipment
All of my observations were done in my driveway. I live in the far suburbs. The Milky Way is visible with the bright light dome from Richmond washing out the eastern sky. My driveway is on the western side of the house, blocking out the light dome.

My main telescope is an 18" f/3.5 Dobsonian made by Ryan Goodson at New Moon Telescopes. I’ve had an 18" since 2008, and this version since 2017. The main eyepiece is a Nikon 12.5mm giving 147x magnification. Navigation is by Telrad and 50mm right-angle, correct image finder. In 2019 I added a 12.5" f/4.5 NMT dob. With the 12.5 Nikon it gives 129x. Neither scope has Go-To or DSC’s.

I have a small table to hold the Uranometria, iPad with Sky Safari, notebook, flashlight and pens. I use a simple notebook and write down observations as made. I have trouble writing in cold weather with gloves, and later trying to decipher my writing. Each entry is verified later in Sky Safari. One digit off and a star is in a completely different constellation.

 

Images of Uranometria courtesy of the American Astronomical Society and Willmann-Bell
Object information courtesy of SkySafari

 

Doubles in the spreadsheet can be referenced in https://www.stelledoppie.it/

 

Note about using non WDS identifiers: on the attached spreadsheet I have included HD, HR, TYC or other star catalog designations as a check on the main WDS identifier. According to Wikipedia "HD numbers are widely used today for stars which have no Bayer or Flamsteed designation"

and "and its catalogue numbers are commonly used as a way of identifying stars"

 

Most alternate star designations can be investigated here http://www.wikisky.org/

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•  Canis Minor Doubles.ods   32.7KB   35 downloads
•  Canis Minor RA and DEC graphical chart.ods   18.32KB   24 downloads

[tdfwds]

Very impressive and very nice.

 

As I couldn't be bothered to reboot into my linux usb stick and use libreoffice I tried a couple of online converters, and for those also wishing to do so, .ods converted best in this https://www.aconvert...ent/ods-to-doc/ , although I believe later version of .doc and .docx using machines can convert .ods cleanly, so maybe irrelevant.  EDIT .ods is a spreadsheet format!!!  So I was an idiot there!  If you can't read it for whatever reason use an online .ods .xls or .xlsx converter.

 

NOW, it's Schwarze Freitag or Vendredi Noir or whatever where you live, research yourself some cheap modern dictaphone that can run off (a) rechargeable(s), or just use your smartphone, I think most of them have a record option.  If you're drawing at times as well you'll still have pencil and paper but won't need it so much.  Pick one with an easy to use by feel on off switch and an 3.5mm jack audio out.  You're apparently transcribing your rough notes anyway.  It does make all the difference, unless are in danger of annoying someone at 3am in the morning, but you can whisper.

 

Keep them finger tips warm as long as possible, mine used to give out afore the big toe tip, which was the worst offender no matter how coddled.  I starhop too, and t'other night the tube, despite being a synthetic plastic, got more damp than cold at first, so hands can be an issue.

 

You'll wonder why you never did it afore!  From the look of the kit you can afford you can't be short of a bob or two (idiom).

 

I used to use an old handheld job with microcassette, which was a bit bulky albeit hand sized, and the batteries added a bit of weight, but don't get one too small.  You've to balance between cost, likelihood of dropping it when taking it in and out of a pocket or somesuch, or not rolling when on a surface if you use a desk or such, not too small, not too light, not too cold or too sweaty hand making a surface, but just right (but don't feed it porridge), with an easy to use handfeel on/off switch.  Maybe even a lanyard (an around your neck thing).  Most digital ones likely have a decent mike, and as I say with a standard 3.5mm jack audio out ear buds or just oldstyle headphones for transcription.  Non-fiddly rewind would be nice too for during transcription, however that's a learn the hardway thing.  Although the freeware audacity allows you to take such stuff via your computer's audio line-in (every computer going, usually) and you get a sonogram so you can click along where you want to start, for barely a few seconds launch and load for small files.

 

Just a thought.  If I was doing long observing sessions, especially of new stuff, I'd certainly get one.  Unfortunately what little chances I get is refamiliarising myself with old pals due to the suburban glow nowadays.

 

Things will come back to you as you hear, just as they do when you transcribe writing, and if you can partway type or are a fast hunt and pecker, you can key your logs into the computer pretty fast without having to keep glancing around, should that be where you log stuff.

 

WARNING maybe not use the smartphone, even if it has audio editing app, they tend not to bounce well don't most smartphones, and appear readily droppable.  And if it only records in oldstyle .amr, definitely don't bother!

 

 

PS Likely it didn't matter to you whether the doubles were optical or not, but just fyi, GRV 742 is purely optical [JDSO 16 362 Table 1] whilst GRV 747 is physical [JDSO 15 59 Table 1]

Edited by tdfwds, 26 November 2021 - 01:43 PM.

[tdfwds]

Now, just in case, this is in no way meant to be critical, this is just an FYI for some of the doubles you didn't have a discovery code for.  You've noted one of them as problematic in your own spreadsheet :-

 

WDS 07428+0404 = AMS 3  -  A. AMOSSE, sometimes alone, sometimes with co-authors, something called Obs. et Travaux (French) and also the odd IAU DSC*

 

WDS 07477+0244  =  DAM 1223 AD  -  F. Damm, no refs other than pers. comm. at WDS.

 

WDS 07155+1313  =  probably a typo?  Not in WDS.  WDS 07155+0313 is OL 195. and not the HD star mentioned, there is no HD designation.  OL is C. P. Olivier.

 

WDS 07226+0620  =  AHD 37  -  A. Ahad.  As you say, the third star is apparent, not physical, and not logged in WDS

 

WDS 07452+0726  =  AHD 38  -  A. Ahad.  Tyc 0192-0267-1.  Your Tyc star is the one half an arcmin Northish, and is optical.

 

WDS 07469+1136  =  DAM 804  -  F. Damm

 

WDS 07500+0241  =  unclear - the BD identifier is for Jonckheere (J) 2046 but that is WDS 07501+0239, which you have as +0236 in its own J entry.  BD +03 1807 is J 2046.  WDS 07500+0241 however is J 2044.  You have separate entries for both of those, they are 4' apart.  SIMBAD is telling me that J 2044 is part of a new Galactic Open Cluster Herschel 1, a massive 80 arcminutes across.  It was claimed new from a GAIA dr2 - Tycho2 study in 2018.  However, there is also a 2005 reference to a paper on 109 New Open Clusters.  Very common when lots of new surveys come out.  There's also a 2011 paper asking "open clusters or asterisms" using 2MASS near infrared colour magnitude diagrams to analyse said question.  Open Clusters can be considered effectively equidistant, so you can use apparent magnitudes instead of absolute ones when you don't know a cluster's distance.

 

* IAU Double Star Circulars www.usc.gal/astro/circularing.html

 

NB on your chart image, the unlabelled double star nearest and a little below UGC 4010 is HDS 1102, 0.4" and delta_mag of 2 and a bit.  The one nearish the +04 degree line is STF 1137 which you've observed, and your apparent double is exactly that, apparent.  Finally, and a bit sideways, W UMi is a carbon star so should have given a good shade of red.

Edited by tdfwds, 26 November 2021 - 03:09 PM.

[The Ardent]

I posted about issues with identifying some of these earlier this year. It appears that a nearby unrelated star is caught up in the double star designations. 
 

My guess is  star may be used an “anchor” star for the large observatory , either to confirm the position of a faint double, or as an easy way to repeat the observation if the faint double isn’t in the mount’s database. I don’t know. 

The faint and obscure doubles probably aren’t verified for accuracy very often. 

 

https://www.cloudyni...50313-hd-56035/

 

In any case, I saw something noticeable and logged it. 
 

Thanks for taking the time to post your analysis. 
Ray

[tdfwds]

I posted about issues with identifying some of these earlier this year. It appears that a nearby unrelated star is caught up in the double star designations. 
 

...

 

https://www.cloudyni...50313-hd-56035/

 

Aha!  That likely means that the only reason they were right in my two week old update of WDS was because either you or someone on your behalf had sent those corrections off to WDS!  Makes sense.  There is a way to submit corrections to SIMBAD, or was.  You get a registration, then you can log in and leave a comment.  Can't remember the details, or for that matter my login, as I haven't used it in years, so things may also have changed.  They eventually get around to checking the comments and I think they add them if it fits, complete with your wording.  Maybe.  I can't actually remember, I haven't done it in ages, and it was primarily related to some stuff I was doing which coincided with the onset of the service, which is quite old now.  There's one for VizieR too, but you've really got to know what you're doing on that one if you don't want to really embarrass yourself, so I don't think I ever touched it.  Tons of objects in VizieR anyway, so you would be commenting more on the catalogue as a whole rather than an entry, which is a whole different barrel of kettles.

 

Remember the HD and HDE catalogues were never astrometric.  Coordinates were only added later, and these old files have been sometimes used in more modern further cross identifications, such as HD-HIP.  I think it's called propogation of error, or something, when this happens.  I know when I GOTO HD numbers in Guide 8/9 it rarely lands on the actual star, and it uses an ADC (astronomical data centre) file.  Strangely though when you do click on the object it is correctly in the list of cross identifications.  WDS used to have a cross identification file according to my memory, it may have dissappeared when the 1996.0 CD version or the slightly later one that used 2MASS to tie down the J2000 coordinates better were released.  I think I ditched most if not all of my old ADC CDROMS from the early 90s years ago, so can't be sure.

 

 

UPDATE : I've read the above link, suddenly remembered my simbad login, and sent an error correction.  Sorry, I haven't been able to credit it to anyone as I don't know the full names.  I sent it as a correction, so likely it won't get annotated, as there are now two separate team notification options, i) report an error, ii) post a note.  You just get one of those little webform feedback little message box things that are very popular nowadays.  We'll see if SIMBAD corrects itself as a consequence, as I haven't mentioned all the background info in order to avoid confusing the issue even further!  Also, I've no idea what email address I had in those days when I registered (which was mostly for sending cross ID corrections stumbled across during variable star tasks), so if they ask for clarification via email it is going to bounce because it will be long gone, and that is never considered good by anyone.

 

EDIT : I got that wrong, you can view the annotation even on errors, just scroll to the bottom of the HD 56035 SIMBAD page and you'll see a link to view it.  That'll teach me.  Remember, people can register themselves, you just have to try and send a concise and authoritative bunch of current catalogue or data evidence in support (don't get bogged down on the history of it, or as longwinded as me).  Remember that the staff there may well get flooded with these and no doubt no matter how hard they try to be objective certain 'bad penny' names are bound to stick in their craw.  Actually, I don't remember having to give a real name, just a username and authentic email address for authentication, like the usual thing.  Probably a no robots ddos protection in there nowadays too, at a guess.

Edited by tdfwds, 26 November 2021 - 05:38 PM.

[c2m2t]

Hi Ray!

What a great project and a thorough approach to the task at hand. Sooo...did you hold yourself to a month?? How many nights of observing were involved??

 

After going through your spread sheets and checking my own processed images, I really need to ask why you felt that these two obscure compact doubles so captivated your visual sense. There are some very interesting star fields throughout the constellation. Looking at the SDDS image for J 44 and surroundings, the brighter stars in the field have a Sagitta thing going on. The arrowhead is pointed north with A 2870 at the tip. Your other double of special note, BU 21, dominates a fairly empty field...at least for the 4 and 5 inch refractors. I suspect that 18 incher tells a different story.

 

One final question for the doubles summary...I see some red highlighting in some cells...does this mean anything??

 

Well done!!

 

Cheers, Chris.

[The Ardent]

Chris 

The red cells are where I weeded out duplicate observations. I forgot to remove the formatting. 

 

It took almost twenty sessions from December to April. 
 

All I can say is when viewing , if I noticed it I wrote it down. 
 

I will get around to posting the other things. 

[tdfwds]

Just had a check of SIMBAD and they appear to have fixed the OL 195 / HD 56035 mix up all already.

 

HD 56035 has been de-doubled and the cross IDs removed

 

http://simbad.u-stra...ius.unit=arcmin

 

And for OL 195 itself, instead of ignoring it (as they don't have all double stars in SIMBAD linked to their main catalogues, they have created 3 entirely new entires.  Why they've chosen WISE to denote the double star, I know not, probably so they can free up the other two identifiers.  The Tyc identifier is an entry for the A star and the UCAC4 one is for the B star, and they've all been linked via their relatively new (been around a while actually, but didn't used to exist) parent, child, sibling hierarchy linkage.

 

http://simbad.u-stra...ius.unit=arcmin

 

So there shouldn't be any future confusion in SIMBAD at least.  OL 195 is in the right place in current WDS but I haven't really checked the full WDS entry. for it.

 

Any other database or software suite still having the old info is their author's problem, though ones purely using WDS for OL 195 should be fine.

[Bigzmey]

Great project and execution Ray!  

[The Ardent]

Not that anyone is keeping score, but I found a straggler that I had entered on the wrong spreadsheet by mistake. 

 

Name  14 Cmi = SHJ 87 

Date 04/02/21

Scope 18 NMT  12.5 Nikon

conditions : clear, cold, slight breeze start 20:25 pm

Note: bright star with several wide companions

 

https://www.stelledo...?iddoppia=36767

[c2m2t]

Hi Ray!

I felt compelled to add some visuals for at least, one system, in Canis Minor.  And since you highlighted SHJ 87, it made sense to add it here. A rather nice system if I don't say so myself. CMi has many interesting doubles but being a winter constellation for us north of the equator, for many, a road less traveled. Enjoy!!

 

Cheers, Chris.

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