Doubles anyone ?

[bigjoe]

Hello fellow IISers..

No its not Tennis.

Eugene(Bombardon) and myself(bigjoe) have come up with the idea of a Monthly Constellation Doubles observing report.

We'll tommorrow post the Doubles selected in the Constellation to be observed for that month...giving you plenty of time to observe and report due to weather.

We though we'd choose 6 of the many doubles in ORION to kick it off.

Suggestions for these Monthly Constellation doubles reports, selections etc are also welcome ..esp from Tinderboxsky(Steve) Mekon(John) , Steffen etc.

Though nothing too technical, such as stating position angles as mandatory...as this is for the uninitiated also.....So how to best go about it..PICK some say MAX of 6 Doubles per Constellation..and not always the obvious ones .

This will be for anyone interested in Starsplitting as part of their observing regime...Novice or Veteran.

Even if your not an avid doubles observer, we would like to hear of your observation .....even if you only get time to observe just one of those selected in your humble 60mm Tasco, let us know!

Resolution limits for your aperture, use either...

The DAWES LIMIT for YOUR scope ..116/Diameter in mm..barely will you see a hairline split.

RAYLEIGHS LIMIT 138/D mm a clear dark line will separate them in comparison.

These LIMITS ALL are based on components of equal magnitude; in practise most doubles are NOT Equal, and tougher.


Tell us about how HARD or EASY it was in your scope, at its RESOLUTION LIMIT e.g. Say 1.1 " in a 4 inch, in as good as seeing as you can..don't worry too much about transperancy..its really the seeing thats important... WHAT WHERE THE ...

Stars selected and observed..state their mags and separations when reporting.


Scope and Eyepiece(s) used .

Magnification(s) used.

Colour Contrasts seen .

SEEING ,Transperancy at the time.

LOCATION, Time, Altitude above horizon(can estimate).

Separation will be given, but is it as stated?.. this for the experienced ones.

PA... Is PA stated accurate..though this is NOT necessary, only for the expert .

Type of doubles observations....you'll need very good seeing at least for the first three.

1: Was it a figure eight..unsplit
2: Kissing and unsplit
3: A hairline split = split
4: Or best, a solid split .

Some doubles will be tough, some easy...the point is to have a go at some, and have fun testing your optics at the same time!

And remember no matter how inexpensive your scope, how cheap your Plossls, Kellners are ...we'd like to hear from you...NO Elitism or bagging scopes welcome .

Remember also SMALLER instruments produce LARGER AIRY DISKS at high magnifications, and can actually be BETTER in poorer seeing than LARGER instruments.. this Airy Disk size, or Diffraction Limit for aperture is inversely proportional to the increasing aperture.

Larger scopes...... some with central obstructions, and their resulting SMALLER Airy Disks, bright diffraction rings or spikes can obscure a faint secondary, long cooldowns, thermal currents crossing mirrors, heat plumes off baffles etc... these need more time to cool down.

Try to use 1 eps as a Standard eyepiece IF you want to judge separations..though this is NOT NECESSARY here, VIZ....

Know what say 10" arc looks like in your go to eyepieces for example as in Rigel.

Formula for this..... OCULAR FIELD STOP in mm X 57.3 / FOCAL LENGTH OF SCOPE IN mm.
EG: EP Has field stop* 3 mm, scope 1719 mm focal length

Then thats .. ( 3 x 57.3 )÷ 1719 = 1/10 degree true field of view or 6 mins of arc or 360" IN YOUR EP....So if a Double has a sep of 36" it will be one tenth of the field width of YOUR STANDARD EP, so you'll get an idea of separations and were the secondary will be in your scope!

You really only need a few EPS for this, a locator widefield , Zoom or some higher powers, and optionally a Standard EP for judging separations...all with a Flat Field.

PS: Remember also ...
MOST SCOPES ABOVE 4" ARE SEEING LIMITED AND NOT DIFFRACTION LIMITED most nights of the year...So be patient get a nice comfy chair, and wait for that moment of good seeing ...it will come...you have a month to report!

bigjoe.

[The Mekon]

OK Joe, off the top my head for Orion - 6 stars

1. Rigel - easy
2. Lambda - easy
3. Eta - fairly difficult
4. Psi & Struve 712 (in same field) - not easy!
5. Alnitak - not easy
6. 32 - quite difficult.

Could add another couple of dozen interesting stars - what is the next constellation?

[bigjoe]

These are all crackers John, and only 52 ORIONIS we had, not on your list..will consider all these for tommorrow.
PS: May have to make it a few more.

Cheers bigjoe.

[Suzy]

My head hurts :P:lol:

Seriously though, that's a great idea, I hope you get some decent interest.
Math does my head in so I really liked what you said with hair split, figure 8 etc. :D

The Astronomy 2018 book has a section for double stars also, I think each month.

For the more experienced observer, here's a challenge, if I may throw one your way?

Sirrius in Canis Major is good viewing at the moment. Split its white dwarf companion. This is easier to do in the evening before the sky gets too dark as Sirrius won't appear so bright, overpowering the dim dwarf. I've been successful at getting it using 120x mag (10mm ep) with a 10" scope.

[bigjoe]

Nice to hear from you Suzy...

Yes indeed Sirius; that should be the next one we do with Canis Major..then Gemini perhaps..

Sorry about the arithmetic Suzy... believe me theres much worse I could have included..

Hope you might have a shot at one we will include in tomorrows list ..everyone who wants gets a month to do so.

Cheers bigjoe.

[bigjoe]

John...
Suzys suggesting Canis Major... there, maybe also Lepus or Gemini next.
bigjoe.

[xelasnave]

Hi Big Joe
I doubt my scopes are useful but I would love to have a go...if possible.
I have a 80 mm which is maybe too small I guess, an eight inch newt and a 150 ed refractor ...I am not sure if I still have a 12 inch it may be gone.
Am I under equiped?
Also the though popped into my head and I suppose its been done but do you know if any one has taken photo over time and made a little movie like the recent one of our closest star which was over five years from memory.
Alex

[bigjoe]

Yes Alex . What a GREAT IDEA...some pics through your and others scopes would be great with these reports ..most of the doubles selected would actually be viewable in your 80mm at 1.7" diffraction limit...and high diffraction power...one or two would need your excellent 6" Refractor for sure..will be posting a list for Orion morrow..and my attempts at some..Respect always.
bigjoe.

[xelasnave]

What was proposing was to take shots over a period of months or maybe years so strung together you may see a particulat double orbiting via an animation.
Alex

[bigjoe]

.
. Even better than just taking a shot...Yes why not I say...some have very slow orbits some quite rapid in only a few years..They use Keplers Laws from the PA and sep of stars over time to help calculate their Period, Masses, distance..etc .another great idea.
bigjoe.

[bigjoe]

What Alex is getting at, is that for example, orbits like at the bottom of this web page
http://stelledoppie.goaction.it/index2.php?iddoppia=60453
can be photographed or observed over time..thats how they calculate their Period,Masses ,distances between .... use the wonderful Stelledoppie website you'll see all info ,orbits etc
bigjoe.

[Tinderboxsky]

Well done Joe and Eugene for taking the initiative. I'll be a participant and contributor.
Looking forward to your first list. I like the way John has ordered his suggested list with each successive target getting more difficult.
Of course it is raining here!

[Tropo-Bob]

I like this idea as well.

I would suggest that U simply pick out a constellation or more each month n title it: Doubles in (Constellaton) and that way it would be more easly found than say: Doubles for February. Sorry to overstate it, if this was already the plan.

For Doubles in Orion, the doubles that immediately come to my mind are:
Rigel
Zeta
Eta
Lambda
Sigma.

Nevertheless, I will be interested in being informed of other fine double outside of my favourites.

Alex: I had the idea of tracking movement in Alpha Centauri, but only took one photo (yes, film) in the early 1990s, then gave up. Pity.

My computer is out ATM, this has been done on my mobile; so apologies in advance for any typos.

[bigjoe]

Looking forward to that Steve..

Yes first month no STFs etc, really till people get the hang of it just easier ones to locate first up for the Novice who may want to try.

bigjoe.

[bigjoe]

Great selection Bob ..

Thats what well be doing ..posting a Constellation for that Month.

With ORION first up, then probably Gemini , as Castor, Propus , Wasat, 38 etc are great...with some other selections from you and Steve as well.

PS: A centauri..wow what an effort to try.

bigjoe.

[gaseous]

Great idea Joe, if these Brisbane clouds ever clear, I'm in.

[bigjoe]

Looking forward to your report on some of those attempted Pat... how you go with them in your scopes and EPs..some will be tough some easy..its for all ..not many STFs etc will be included, to make them easier to find first up.

Cheers bigjoe.

[xelasnave]

Tropo-Bob

Hi Bob.
You would not believe I was thinking about such a project last nigh as my head was on the pillow.

Can you imagine what it would look like over time...I think it would be like an electron cloud, at least the way I imagine one.
I was thinking all about the various objects over time...
There may be globulars that have more movement than others that could be the object of such a project...but if I was younger and starting out I would be doing several...
Say you are twenty imagine the neat stuff you would have by my age...fifty years fifty projects...now theres a thread title if ever I saw one.
Alex

[bigjoe]

Well Folks....

EIGHT Stars have been selected for this months Constellation......... ORION.

Try all, or any in your scope and EPs, and tell us what you see...ALL NOVICE AND VETERAN Astronomers welcome to have a shot.
Remember....
PA is just the position angle, no need to worry about that here.

Some Stf and Herschel stars, will be included in next months Constellation . Most selected will be readily seen, and found in the screen shots off SKYSAFARI PRO below.

This months List for ORION is....

RIGEL(Beta Orionis): Separation 9.5". Magnitude of pair AB : 0.28, 6.8.
PA 202°. What do you see?
RA 05h 15m 24s DEC -08°11' 02".


31 ORIONIS: Separation of pair is 12.8". PA 88°. Mags of pair AB: 4.7, 9.7 ...An absolute GEM...Colours seen?
RA 05h 30m 38s. DEC -01°04' 52".


RHO ORIONIS (p ): Separation 6.9". PA 62°
AB: MAGS 4.5, 8.5.. a pretty double.
RA 5h 13.1m. DEC +02° 51' 40".


SIGMA ORIONIS: (σ Orionis).... Superb.
AB Combined at Mag 3.7, is too close to separate for anyone, star C at magnitude 8.7 at a Separation of 11.6 " away from the AB pair isnt....
with two magnitude 6.6 stars, Called D and E, at separations 12.7" and 41.50" respectively from the AB pair ......so you'll actually see four coloured stars.......
What colours do you see? Lovely Struve 761 a triple also in FOV.
RA 05h 38m 45s . DEC -02° 36' 00".



ZETA ORIONIS (ALNITAK): Actually a triple! A, B, C. Near the Horsehead on the charts below, and PART OF ORIONS BELT.
PA 167°.
Magnitudes A: 1.77 , B: 3.7 , C: 9.6
Separation AB: 2.18″..... Sep to BC: 58.0"
RA 05h 41m 39s DEC -01° 56' 10"

SAIF AL JABBAH (ETA ORIONIS): PA 77°..SEPARATION 1.8"..Looks like an n on the SS charts below.
AB: Magnitudes 3.39, 4.89.
RA 04h 24m 09s DEC -02° 23' 50".


32 ORIONIS: PA 44°... Separation 1.3". Brightest star just inside Orion near Bellatrix. MAGS AB: 4.23, 5.75 .
RA 05h 30m 47s DEC +05°56' 53" .
Use DAWES LIMIT for your scope as equal enough..Sep given in Eaglecreek observatory and elsewhere is wrong..not 0 .7".


52 ORIONIS: SEPARATION 1.0" PA 220°.
Mags AB: 5.99, 6.03 ............Very, very, TOUGH, at or near 120mm aperture; needs very good seeing with aforementioned aperture...at least they are equal pairs, making it easier than otherwise using Dawes limit for your scope.
RA 05h 48m 58s DEC +06° 27' 27".

Remember were not twisting anyones arm here, were aware of many peoples Double Star Inertia....No obligation to try them all; a few sentances will do, on what you've seen, equipment used, EVEN high power Binos that some have , and magnification used will do, when you have the free time for this months Constellation, observe then post.

PS: As usual any amendments, or suggestions for next months Constellation welcome.

Cheers and goodluck bigjoe.

[Wavytone]

Righto you’re on. I’ll be set up by 9:30.

[bigjoe]

Myself a few later around 1030pm ..who else is game for a few tonight !
bigjoe.

[Wavytone]

I skipped straight to 32 Orionis... a nice one and easily split despite poor seeing. 52 was harder but glimpsed as double at 450X, two little Airy disks touching (Dawes limit for this scope is 0.5 arc sec). Should be straightforward in decent seeing.

First decent look at the moon too through this beastie... awesome. Might have a go at rigging up a camera sometime given the planets in a few months time.

Didn’t hang around though as it’s a horrible night 30 degrees and 90% humidity.

[bigjoe]

Im going to report morrow perhaps Wavy.. quickly split all except 52 tonight; you got 52 kissing with some black between sometimes? If so thats very good....pretty ordinary night for splitting anyhow...So need to retry.

TOUGH 52 Orionis in Skysafari Pro screenshot below.

bigjoe.

[The Mekon]

I was set up by 2030 last night, first quarter moon below Orion.
Using my 106mm refractor (easiest set up) as I was unsure how long I would get going on the forecast.
Well I got a great two hours and the seeing was quite steady, bagging the first six on Joe's list before moving into Canis Major. I avoided 32 & 52 as I have large trees to the north and west and stars at this declination just graze the top leaves of those trees.

Amazing that I could observe at all, since it promised rain in the afternoon and now has delivered down here in the Highlands.

[Tinderboxsky]

Cloudy. Say no more. :sadeyes:

[rrussell1962]

Utterly clouded out in Brisbane, but have dug out some observations of Orion doubles from the past 12 months with varying equipment. These are what I wrote down at the time except the magnifications which I have added. The notes were never intended for public consumption so are very brief, but I didn't want to start adding things with hindsight. I will make better notes in future! Quite often I set up 2 telescopes for comparison purposes, I hope I have not mixed up which one I was using. If you think I may have done, please point it out.

30/1/17 Seeing good 8/10 Vixen ED80 F9
Rigel 5LVW Good view, well split, secondary v.clear x144
Pi3 Ori 5LVW Primary yellowish, secondary v. faint x144
Rho Ori 8LVW Primary yellowish, secondary blue speck x90
Struve 667 8LVW, orange hue, secondary off white. x90
23 Ori 8LVW both blue / white. x90
Wnc2 8 LVW, close but easy split, equal brightness. x90
Eta Ori 5LVW, very elongated, split at times. x144
33 Ori, 5 LVW, clear split x144
Lambda Ori, 8 LVW, split, easier with 5 LVW x90 x144
Iota Ori, 8 Ethos, secondary lovely faint speck x90

1/2/17 Vixen VC200L, seeing OK 7/10 with better moments
Wnc2 13LVW and 10 Delos, clear split x138 x180
Eta Ori, 13LVW, 10Delos, 8LVW split at moments, 5LVW pushing too far with seeing x138 x180 x225 x360
33Ori 10Delos, clear glimpses, 8Ethos same x138 x180
32 Ori 8Ethos, just split at times x225
31 Ori, 8Ethos gold and faint blue x225

4/2/17 Vixen ED80 F9 Seeing good
Alnitak, clear split 3.5LVW pushing it! x206
Eta Ori, split 5LVW, better 3.5LVW when seeing steady, just split x144 x206
Eta Ori, old Vixen 0.965 5mm Ortho and diagonal, just split but V CLEAR c/w LVW x144

17/2/17 Nexstar 8SE 7/10 seeing
14 Ori Elongated but can’t say good split 8LVW x254
Alnitak 8LVW clear x254
32 Ori 10 Delos 8LVW both close but clear x203 x254
Trapezium 13 LVW E and F visible.

8/2/18 Obsession 18 F4.5 P/Corr Trans 6/10 Seeing 7/10
Rigel mostly steady, Capella Some twinkling @ 1 sec intervals
8Ethos Orion doubles x291
Iota, lovely triple!
Sigma, nice splits, good!
Struve 761, 3rd star wide
Lambda (Meissa) Clear, nice
52 Ori, easy split tonight, equal and f.bright tried 8LVW - split but not as good
Alnitak, nice, clear
42 Ori,
32 Ori
Eta Ori nice split

[bigjoe]

Poor seeing, and humid here in Sydney last night John bagged all except 52.

31 Orionis..A very attractive pair..easily split at near any magnification even in 20mm Vixen NLV ...big Orange Primary and small Blue fainter secondary, a real treat and highlight so far for me in the 130mm Triplet with Tak 9mm Abbe Ortho.
Had a quick crack at 52 Orionis with the Tak TOE Ortho at 275x , but unsuccessful so far...still got the month to try.

bigjoe.

[bigjoe]

Been ordinary here too Steve..still got near a month for us to try crack all of them.

I think some of next months selections we have planned will be a bit tougher even.

bigjoe.

[bigjoe]

Thanks for this Rus ..I'll sift through them and have a look at my reports.
bigjoe.

[Tinderboxsky]

Yes, still some time left. However, with the very long and later twilights down here it will not be long before Orion is too low to chase the closer doubles.

Just a thought as you prepare the next list of double star targets; would it be worthwhile starting a new thread for each new list. It may make following members reports and comments a bit easier.

[rrussell1962]

It was interesting going over my notes for the past year. What stands out, to me at least, is that aperture does make a difference. What typically happens with my Obsession in Brisbane is that I take it out to around the same temperature as the house where it is stored shortly before sunset and it performs well for an hour. Then the temperature drops and it all goes to S*&t for an hour or so. Then is slowly comes up to speed and after 4 hours or so it is seeing limited and will basically do anything I want it to do. Oddly enough the Nexstar 8SE, despite the corrector plate, cools quicker than the VC200L - when cooled there is not a lot to choose between them, despite what "You Know Who" on Cloudy Nights might say. I have just acquired an ED100 and am looking forward to using it on doubles in the coming year. A lot of my double observations are part of my, incessant ongoing attempts to collimate my VC200L. I have the feeling that it is a very nice telescope, but a bit more fiddling with the Primary / Secondary spacing is needed, it does not "snap" into focus just yet. When it gets to that time of the year I will have a crack at Beta Muscae again.

[Bombardon]

Great effort, Joe and all who have taken up the challenge on what is rapidly becoming the Southern Star Splitters! I think Joe has not only come up with a great introductory list for Orion but he has even sent many of us back to our notes from past viewing sessions.
Joe has covered all important aims and objectives in the group, especially making sure that the size of optics and experience don't matter and so long as we all get out to our favourite viewing spot and surprise ourselves with doubles visited for the first time or the tenth, and share our notes, we will all benefit. Personally, most of my splittings have been on easy separations, being a Dobson fan for many years and suffering from skies that are often disturbed by my closeness to a river and the evening fog and moisture that results. I promise to attempt the closer 'Oysters' from now on.
Ki9nd regards and good splitting to all, Eugene

[Bombardon]

I missed an early start on what a viewing buddy down here tells me was a bottler last night but I am adding a report on five from January in 2017.
These five In January 2017 using 10” F5, 13 mm Hyperion Eyepiece .
Zeta Ori (Alnitak);RA 05hrs. 40.7mins; Dec -01° 57’; c) 2.6”; d) 166 e) m 1.9; 3.7. This is a challenging double but worth the effort. I needed my highest power eyepiece x250 to separate, yielding a stunning Yellowish and White close pair that will need a 4” lens and good seeing to prise apart. I found an aperture reducing mask helped.
31 Ori; b) RA 05hrs 29.7 mins; c) 12.8”; d) 87°; e) m 4.7; 9.7
This one barely rates a mention in the annals and lies neglected near Orion’s Belt(see map below). However, though seen for the first time this season, I found the contrasting brightness and colour on medium power x180 made this a classic already in my collection. Primary orange with a faint blue companion in a rich field.
Rho Ori; b) RA 05hrs 13.1 mins; c) 7.1”; d) 64° ; e) m 4.6; 8.5
Rho(ρ) looks a little off the beaten track, but it is well worth the search. Again, a stunning contrast: primary, orange and its faint companion a light blue which seems well separated at medium power.
contd

[Bombardon]

Sigma Ori; b) RA 05hrs 18.7mins; c)11.5”; d) 238°; e) m 3.7; 8.8.

I have left the best till last. Sigma (σ) is familiar to Horsehead hunters, sitting as it does just outside the field but often passed over. All double hunters are in awe of this one. First observed 250 years ago, it was found to be two separate star systems forming a wedge-shaped grouping in the field. My drawing made at the eyepiece suggests two groups of three stars with the sixth star some distance east (front to back of ‘wedge’ is approx. 8’). Under high power the brightest of the seven, stf 3135 I have split to make 8 stars in the field. It looks like a planetary system in a moderate eyepiece with white and blue stars whose formation is reminiscent of the close packed Saturn satellites when the rings are edge-on.



Rigel.B Ori. This is a challenge to me and split with my 9mm Meade HD60 on about one night in 4. High cirrus often helps or early evening stillness.



Kind regards and good viewing to all star splitters everywhere.
Eugene

[bigjoe]

Absolutely Steve.

Next will be posted as a New thread ..No sense in dragging an old full thread out, and trying to look for information etc.

Next posts selection list will attend to our more southerly members...and We'll be putting up a list, and invite you and others for that months input and suggestions.

Will do in 2 weeks or so ,to prepare early.

Cheers bigjoe.

[bigjoe]

Heard that the VC200L has a special coated and figured mirror that can only be redone at the factory if needed, but has very flat, sharp field and is not that easy to collimate... heard the VMC 260s virtually arrive out of collimation most times.
The C8 has smaller obstruction, no diffraction spikes, no open tube currents too, and should have better contrast on Planets...though not the build quality of Vixens.
Finding myself the refractors and Maksutovs , generally are ready quicker than an SCT or big Dobs or variations of...

If seeing good, aperture and quality still rules of course.
PS:Beta Muscae..now thats tough.

bigjoe.

[bigjoe]

Yes Eugene.....

RHO ORIONIS (p ) 6.9"*** PA 62°
AB:* MAGS 4.5/ 8.5* ...... I see Golden Orange Primary*, tiny deep blue secondary....absolute Gem visually RA 5HRS 13.1m DEC +02 51
40...FIND OF THE NIGHT.....

Detected in 20mm Vixen NLV and split easliy with 8mm DUAL ED OR TAK 6mm Abbe at 150x in the 910mm Triplet.


32 ORIONIS* PA 44° SEP* 1.3" Brightest star just inside Orion near bellatrix MAGS* 4.44, 5.75 .......used 3.3mm Tak Toe Ortho at 276x .... 1big* white , 1tiny yellow orb hugging the bright primary* kissing to split at times.* RA 05h 30m 47s DEC +05°56m 53s

Sep given in Eaglecreek obeservatory IS WRONG* not 0 .7".


SAIF AL JABBAH (ETA
ORIONIS)* PA 77°SEP 1.8"..
AB:* Magnitudes 3.63, 4.89** RA 04 24 09* DEC -02 23 50
I see a* big blue white primary and dimmer secondary whitish green.
Used 3.3 TAK TOE ORTHO AND 3.3mm DUEL ED..some lateral colour in this EP though easily did the split

ZETA ORIONIS Alnitak:* Actually a triple A, B, C.
PA* 164°Magnitudes A: 1.77 , B: 3.7 , C: 9.6
Separation AB: 2.18″***** BC: 58.0″.

1big brilliant white with fainter small blue white secondary separated cleanly,* fainter* tiny white C nearby . ..A B split with DUAL ED 3.2mm at 284x* or Tak* TOE 3.3mm* ortho cleaner at 275x.

RIGEL.....* sep 9.5"** Mags AB: 0.28, 6.8 .....** PA 202°** Brilliant big Blue white Primary , small greenish white companion well clear .... and easily split in the TS refractor and* 6mm Abbe151x or 5mm Dual ED easy at 170x in* about* 2" to 3"* seeing** what do you see?***** RA 05H 14M 32S**** DEC -08d 12m 06s.

SIGMA ORIONIS.... σ Orionis .... Superb
Multiple Star... AB Combined at* Mag* 3.7 too close to separate for anyone,*** and star C at mag 8.7* at Sep 11.6 "* away from AB...with 2 magnitude 6.6 stars* Called D and E at sep 12.7"* and 41.50" respectively from the AB pair.......RA 05h 38m 45s* DEC -02° 36m 00s

BEAUTIFUL at any mag I tried ..A JEWEL of the sky like Beta Monocerotis.
Primary AB combo, creamy white, D and E appeared blue and faint purple respectivley. Faint C a white colour on the other side of AB.


31 ORIONIS.... SEP 12.8"* PA 87°.. mags 6.0 ,11.1 ......with 130mm Refractor* at 91x using a 9mm Tak Ortho....Another absolute GEM.* RA 05h 29m 44s* DEC -01°05m 32s
Using 20mm vixen NLV beautiful Orange Star much fainter blue companion..dont use too much power on this...as secondary could dissapear.


Attempted 52 but not much time ordinary seeing and will report back.

bigjoe

[rrussell1962]

I think I have some notes about Beta Muscae somewhere, probably signalling a lack of success! 52 Ori - can't find any reference to splitting it cleanly and consistently other than in the Obsession on a good night when the mirror had cooled. But my observing notes are somewhat haphazardly organised. It would be nice to go through them all and organise by constellation and object type. Effectively they are in season order so it would be possible.

[bigjoe]

Beta Muscae, Rus....
Some sources quote it at 0.7".. others 1.0" or near that......its tough for sure ..luckily the components are near equal magnitude.

I did it once in a SW BD 7.1" maksutov ..Have yet to retry.

bigjoe.

[Suzy]

Thank you Joe for the warm welcome.
That's a nice list, nicely followed by the maps. You've done such great work here. There's a fantastic book I have, which you may be interested in looking up, it's called Sky & Telescope - Stargazing Series - Double Stars for Small Telescopes, by Sissy Hass. It tells you all the info incl. what they look like (lots of Hartung's obs notes!). I just looked up Orion and wow 5 pages!

Hey, you forgot the showcase of them all!
Theta Ori - The Trapezium.

I used to do some of our monthly observing challenges and I can respect & understand how much work goes into these challenges, so good on ya! I used to break mine down into easy, medium & difficult. I found it more fun doing a challenge per constellation, you get to have a more personal experience with it, it's very rewarding. I used to take ideas on one thread (such as this) and then post the actual challenge on a separate thread so it can be easily searched for in the future.

I've been wanting to get into double star observing for a long time, uptil now it's only been the odd one here and there.
It's been enjoyable reading people reports on here.

I should give this a shout out on our fb page :), hopefully give it a bit more publicity to attract more observers. I'll do it when the list is ready, I presume it'll be a March challenge :question:.

[Bombardon]

Thanks for the reminder of the Sissy Haas book, Suzy. I think Joe and I left out the Trapezium as it is perhaps everybody's goto when warming up in Orion. Where I live I can rarely get beyond five but a friend with sharper eyes and better gear reaches the six revularly. Other books I get my doub les from are "The Cambridge Double Star Atlas" by Bruce MacvEvoy and Wil Tirion. Similar to Sissy but good maps. Also check Vol 3 of "The Night Sky Observers Guide" Volume 3 -The Southern Skies by Ian Cooper, Jenn7 Kay and eorge Robert Kepple. On the net Eagle Creek Observatory has great lists of doubles in each constellation and Joe has mentioned -also on the net- StellerDoppie(Sp?) which even shows orbits for many binaries.
Regards, Eugene

[bigjoe]

Once again, thanks for your input Suzy.

Yes I'm well aware of Sissy Haas and her wonderful DOUBLES publication.

And as Eugene mentions Bruce MacEvoys wonderful publications and work on Doubles.

Certainly thats what we plan to do with our next list..VIZ ..
Post list here ,then actually start reports in the proper Report section...some jumped the gun before we did this..so left all for now, as is.

Trapezium ..reluctantly left out!

Looking forward to your possible participation in this endevour..and of course some suggestions by yourself and all, when we post next months list to be ultimately amended .

With thanks bigjoe.

[rrussell1962]

Found my notes on Beta Muscae - complete lack of success. Not a hint of it being a double. It does not help that I do most of my observing from my garden and South is above the roof with associated warm air rising! Great thread Joe, thank you for your effort and I hope to contribute from time to time when my trawling through the Herschel 400 allows. It is actually really nice to see another active visual observing thread on here and gaining traction. Sirius continues to elude me.

[bigjoe]

Its indeed tough..going to put up some tips now.
bigjoe.

[michaellxv]

I had a go at the doubles challenge on Sunday night, although by the time a started looking at doubles it was actually Monday.

Observing with a C8 and 15mm Plossl at 135X. I tried a few different EP but found this gave me the best view on the night. My notes were very brief but here they are.

RIGEL(Beta Orionis): Clear separation.

31 ORIONIS: Clear separation. A appeared yellow and B was blueish.

RHO ORIONIS (p ): Clear separation.

SIGMA ORIONIS: This field is Superb as promised. I didn't record colours but did draw myself a rough sketch of the FOV. I will have to go back to this one.

ZETA ORIONIS (ALNITAK): A & B very close but there was separation, C was difficult to see with 73% Moon nearby. this one prompted me to try a higher Mag but it didn't help.

SAIF AL JABBAH (ETA ORIONIS): I did get separation on this one but clearly affected by seeing.

32 ORIONIS: Only very brief moments of separation, required patience to keep looking. I will need to return to this to confirm.

52 ORIONIS: Could not separate this pair.

Michael.

[bigjoe]

Glad to hear you had a go Michael..

52 IS notoriously tough!
31 and Rho.. very attractive doubles.

Even I need to return to 52 .... thats when the weather clears!
bigjoe.

[MattT]

I’ll join in too Joe.
Last night was sort of OK here in Melbourne...E star in the trap visible but not the F in my 6”f12 Acho and piggybacked 3.5” f11.1 acrho.

I had a go at Altinak which was an easy split with both scopes mounted on my 2” ATM pillow block EQ mount I built a couple of years back.

Sirius was split by both but the 3.5” with 6mm UOVT Ortho showed less scatter than the 6”f12 with Morpheus 6.5mm....swapping them around showed the Ortho has the ‘better’ view...not by much though.I have a TEC turret on the 3.5” with 18 12.5 9 7 and 6mm Orthos in, so it is easy to swap around....better than a zoom IMO.

Rigel....dead easy in both. That was it.

Tonight I’ll try a few less easy ones. Haven’t had the scope out since October last year...it’s been a while.

Matt

[bigjoe]

Great to hear your Report Matt.
Thats what Im finding too .. Less glass less scatter...as good as the Morpheus and the equally good Deloi are... near nothing beats a Good Orthoscopic in near perfect seeing.

The Tak Orthos are ridiculously good Im finding..though the great Deloi , and Morpheus have their place esp in a Dob.

You Bagged Sirius ..great news.
bigjoe.

Tec turret....love those...I envy you.
bigjoe.

[xelasnave]

Hi Bigjoe.
I havent lost interest there is just no lasting sky here and the conditions even between clouds probably not good for doubles.
But its a grest thing you got started...congrstulations.
Alex

[bigjoe]

Thank you Alex for your kind words..
Indeed the skies have been mostly lousy here in Sydney and a bit West as well...need to re- attempt 52 Orionis.

If you get a chance to try one or two thats great.. let us know how you went...your 80mm FPL 53 Triplet alone, should do well on nearly all of these.

Problem I have, is selecting a Constellation thats not too far North for people in Melbourne and Tassie say...its too low, and they have to deal with a thick atmosphere, its refraction effects and turbulance etc

Also, just getting people with a lot of mental Inertia to Doubles, to see how nice some of these doubles actually are...is a task!

Cheers bigjoe.

[xelasnave]

Well it is finally clear here.
And the Moon is absolutely beautiful.
I dont have anything here for the 80 mm to observe with so I am going to see what I can sort out with auto guiding maybe and try some snaps and see what I can do with a bright Moon.
I wish I gad brought another mount so I could image and shot all at once.
I just know if I set up the eight inch it will cloud over so I may just go for a long take on eta..
Ordinarily I would not bother with the Moon but it seems clear so I will try...Anyways it looks great now so I hope it stays nice...I would even be happy shooting the Moon given been here two weeks and nothing like it seems like tonight.
Hopefully a Moonlite night here is better than a dark night in Sydney but matbe short exposures.
Alex

[xelasnave]

Well I am running at the good old 30 seconds on eta at 800 and somehow I dont think with the Moon can get a longer exposure. Anywaysset up has worn me out my legs are on fire and the mozzies are deadly so I will let it run as I recover and maybe hook up auto guide later.
I sprayed this insect spray and it seems to have attacked the plastic in my new little head lamp and its gone all sticky.
Seem to have got the star alignment sortted but I like moving it by hand so its hard to get used to lettingvit slew to an object but it will be good to find doubles easily when I get to them...its all happening.
Alex

[bigjoe]

Good to hear alls coming along Alex.

True, the Moon will stuff up your endeavors...Dam mozzies have sent me packing for tonight too !

We live to fight another day!

bigjoe.

[Wilso]

Quote- They mostly come at night, mostly.
Newt (Aliens)
Haven't had a chance to try your list yet, too much work.
Hopefully this weekend
Cheers

[gaseous]

The clouds finally buggered off from Brisbane last night so I could test these fine doubles prepared by Bigjoe.



Scope and Eyepiece(s) used: Skywatcher 8" goto dob, Baader 8-24 zoom, Celestron Luminos 7mm, ES 82° 4.7mm

Magnification(s) used: 150x (Baader Zoom), 171x (celestron), 255x (ES 82°)

Seeing was pretty reasonable south of Brisbane last night, despite the glow of a very fullish moon right in my face. Stars were sharp up to 150x, but got a little grainy at higher mags.


RIGEL(Beta Orionis): Separation 9.5". Magnitude of pair AB : 0.28, 6.8.
PA 202°. What do you see?
RA 05h 15m 24s DEC -08°11' 02".


Easily split, with a the tiny faint companion at about 5 o'clock (still got to brush up on my PA skills through the dob).

31 ORIONIS: Separation of pair is 12.8". PA 88°. Mags of pair AB: 4.7, 9.7 ...An absolute GEM...Colours seen?
RA 05h 30m 38s. DEC -01°04' 52".

Easily split, with the main star appearing a golden orange and the secondary star appearing a dim blue.

RHO ORIONIS (p ): Separation 6.9". PA 62°
AB: MAGS 4.5, 8.5.. a pretty double.
RA 5h 13.1m. DEC +02° 51' 40".


Easily split, with a main golden yellow star and pale yellow companion.

SIGMA ORIONIS: (σ Orionis).... Superb.
AB Combined at Mag 3.7, is too close to separate for anyone, star C at magnitude 8.7 at a Separation of 11.6 " away from the AB pair isnt....
with two magnitude 6.6 stars, Called D and E, at separations 12.7" and 41.50" respectively from the AB pair ......so you'll actually see four coloured stars.......
What colours do you see? Lovely Struve 761 a triple also in FOV.
RA 05h 38m 45s . DEC -02° 36' 00".


AB appears to be pale yellow-white. C appears to my eyes a faint dusky red-purple colour, or it could have been grey, it was that dim. D appears to be a pale bluey-white, and E seemed to be a yellow-white.


Rough diagram hopefully attached.



ZETA ORIONIS (ALNITAK): Actually a triple! A, B, C. Near the Horsehead on the charts below, and PART OF ORIONS BELT.
PA 167°.
Magnitudes A: 1.77 , B: 3.7 , C: 9.6
Separation AB: 2.18″..... Sep to BC: 58.0"
RA 05h 41m 39s DEC -01° 56' 10"


Relatively easy split, no discernible colour that I could see.

SAIF AL JABBAH (ETA ORIONIS): PA 77°..SEPARATION 1.8"..Looks like an n on the SS charts below.
AB: Magnitudes 3.39, 4.89.
RA 04h 24m 09s DEC -02° 23' 50".


Just able to separate them at 150x, but slightly better division (if a bit softer) at 171x and 255x

32 ORIONIS: PA 44°... Separation 1.3". Brightest star just inside Orion near Bellatrix. MAGS AB: 4.23, 5.75 .
RA 05h 30m 47s DEC +05°56' 53" .
Use DAWES LIMIT for your scope as equal enough..Sep given in Eaglecreek observatory and elsewhere is wrong..not 0 .7".


Jeepers that's a tight one. Just managed a hairline split (maybe) or kissing/unsplit, with a fair bit of imagination at high mag, but if you weren't looking for it as a double you'd pass right by it. Both appeared golden from memory.

52 ORIONIS: SEPARATION 1.0" PA 220°.
Mags AB: 5.99, 6.03 ............Very, very, TOUGH, at or near 120mm aperture; needs very good seeing with aforementioned aperture...at least they are equal pairs, making it easier than otherwise using Dawes limit for your scope.
RA 05h 48m 58s DEC +06° 27' 27".


Not a chance Lance, not in a million years. Not with my gear, eyes, and seeing conditions.

[Steffen]

52 Ori should be quite possible with an 8" tracking Dob, but you'll need way more magnification. My observing notes from 20th January up at the club site in the Blue Mountains say: "Nice close, even looking double, best at 450x. No colour seen". IIRC, I could clearly see it split from 360x onwards. I used a 6" Mak and the 3-6mm TV zoom. Seeing was very good that night.

[gaseous]

Thanks Steffen, I'll give it another crack with the Barlow. It was just starting to look like a pile of golden mashed potato at 255x so I didn't try anything higher, but you've spurred me on to try again. I'd imagine the seeing in the Blue Mountains is considerably better than 1km from the Logan Hyperdome!

[Steffen]

Actually, the seeing is often better down from the suburbs. Try those murky, grey sky nights, they can bring surprisingly good seeing. Most people don't bother because you can't see any DSOs, but for double stars they can be perfect. Also, light pollution doesn't matter, unless you're chasing very uneven pairs with faint companions.

[bigjoe]

Quote "Not a chance Lance, not in a million years. Not with my gear, eyes, and seeing conditions"

Pat.. 52 Orionis, as Steffen suggests..needs a lot of power..even I was unable to go further one ordinary night at about 300x.........Using a Barlowed 6mm Tak Abbe in a 130mm TS APO , due to seeing...YOUR Collimated scope should do it at around 350 x.

Will need to retry myself !


bigjoe.

[bigjoe]

Great to see your much needed input here Steffen...indeed as you state, ultra high magnifications are needed to split some of these tight doubles, esp if the seeing is very good.. then go for it..and yes 450x plus , may be needed.

TV Zoom is by all accounts, a fantastic 5 element EP for this task , with its sharpness, contrast, very low scatter, and ability to dial in the right magnification for the conditions..IDEAL!

Im finding more and more, with EPs and their elements, LESS IS MORE.

Even a good Japanese Kellner, or RKE can surprise on some tight Doubles and Planets...NO NEED for ultra expensive widefields, and their usually increased scatter and discernible contrast drops.

With good Plossls, UO and Fujiyama Orthos,Tak Abbes and LEs, TV Zoom 6mm to 3mm, and even Vixen, Baader, or Bintels Deluxe Orion Zoom, doing outstanding work on these objects.....a GSO 9mm Plossl, and 8mm , 3.2mm TS Dual EDs used, proved up to the task also .

And yes..the City light pollution , Full Moon, and ordinary transperancy has little or no effect on your doubles observing..just one more reason to include some in one's observing regime.

Seeing and Optics RULE here.

bigjoe.

[gaseous]

Thanks gents, cloud permitting I will make 52 Ori my b!tch tonight.

[bigjoe]

I was going to Re attempt 52 Orionis also Patrick..but guess what ..not enough offerings to the Cloud Gods this week ..once again thwarted.
You'd think plenty of squashed blood sucking Mozzies would be enough of an offering, really you would.

bigjoe.

[Tinderboxsky]

At last, a clear night here south of Hobart so tackled Orion doubles despite the bright near full Moon.
Scope: Vixen NA140SS refractor with LVW eyepieces: 8mm-100X, 5mm-160X and 3.5mm-229X.
Transparency looked good - difficult to tell with only one day to a full Moon. Seeing was good, say 9 out of 10. The more difficult targets were at just over 30 degrees elevation unfortunately, which I thought might be a problem.

Rigel @ 100X - straight forward and demonstrated that seeing was looking okay. It is a fine sight; bright Rigel and the companion a brilliant spot. The Vixen throws up some false blue on such bright star, so I won’t try to report a colour.

31 Orionis @ 100X - Primary a yellow/orange with the companion a faint speck.

Rho Orionis @ 100X - Primary a light yellow and the companion a clear very distinct pin point.

Sigma Orionis @ 100X - this is one of my favourite FOV's. The bright primary dominates the grouping, appearing whitish with a hint of yellow. Companion C was faint but clear. The brighter companions D & E appeared pale white with a greenish/blue tinge. The nearby Struve 761 close double in the same FOV was clear. A number of other stars completed the field.

Zeta (Alnitak) @ 100X - appeared elongated with hints of a figure “8” with regular moments of better seeing. Colour appeared white-blue. The faint wide companion C was clear. There was a clear, steady split at 160X A & B.

32 Orionis @ 160X - appeared as definite figure “8” with regular clear splits in moments of better seeing, colour pale blue-white. Clear, steady split at 229X.

52 Orionis @ 160X - appeared as a tight figure “8”, colour pale yellow-white. Difficult but clear, steady split @ 229X.

So, a successful night. Despite my earlier concerns that the elevations might be too low, I was able to split all of the targets. Thanks for the list Joe.

[gaseous]

Those cloud gods are hard to placate...

I've got to thank you and Steffen for the good advice Joe - I've never really hunted tight doubles (tight by my standards at any rate), and have never really pushed the 8" dob past about 250x except for planets, but the 2x Barlow with the 7mm Celestron you sold me did the trick. 52 Ori was split with moderate comfort at 343x, and was still OK at 400x with a cheap 6mm skywatcher plossl. I found turning off the goto tracking and let it drift across the field allowed for more stable moments of seeing. Thanks again - looking forward to next month's list! :thumbsup:

[bigjoe]

Cheers Steve..I see that green tinge also in Sigma's D......stars arent supposed to be greenish ,but thats the contrast I see also.
C is faint on the other side of the rest...52 yet to be cracked...all in a lovely field with Struve 761 and nebulae nearby.
Rho Orionis, an easy gem when viewed high up.

bigjoe.

[bigjoe]

Pat...
Thats a good trick what you did with the tracking....and a good Plossl of 6mm or 9mm and Barlow, is all you need in most scopes for all the DOUBLES here ...my next attempt at 52, Im going to really crank up the power , probably well over 350x!

bigjoe.

[Merlin66]

You may also be interested in the Journal Of Double Star Observers

http://www.jdso.org/

Lots of interesting observations and comparison data.

[bigjoe]

Thanks for this Ken..interesting article on students observation of Delta Orionis for all here too.

bigjoe.

[Stonius]

I'm curious about the theory behind this. How does the tracking of the scope deliver a less detailed view?

Best,

Markus

[gaseous]

Hi Markus,

I've found the GOTO tracking at very high magnifications on doubles and to a lesser extent planets can tend to make the view a little "jerky" as the gears adjust/track, so turning it off removes this jerkiness, and seems to allow for better seeing as the target drifts across the field of view. I then just use the direction arrows on the hand controller to pull it back across every so often. Don't take this as a slight on the goto - I wouldn't be without it and any alleged jerkiness is non-existing on DSOs and other lower-mag/wide field targets.

[Stonius]

That's interesting. Sometimes if Im trying to resolve very small details on a planet I feel like it helps to turn off the cooling fans on my scope momentarily. Maybe its the same sort of thing?

[gaseous]

Quite possibly - anything that causes even the slightest vibration can screw with the view I reckon.