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Asbytec
Guy in a furry hat
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Reged: 08/08/07

Loc: La Union, PI
32 Orionis
      #5513827 - 11/10/12 11:33 PM Attachment (99 downloads)

Interesting that Orion has two tight, (nearly) equally bright doubles inside each shoulder: 52 and 32 Orionis. I believe 32 Ori is a bit tighter than 52, the companion lies exactly on the primary's first diffraction ring and a clean split noted only at higher power about 300x. Below 200x, there may have been a bit of elongation noted.

When I did this sketch last year (inspired by observing last night), seeing was so good I actually tried to see if the companion's rings could be seen crossing into and within the primary's first minimum. Not sure that's possible (due to the laws of diffraction), but seeing was calm enough to give it a look see. I failed to see it.

One thing that was interesting was the companion appeared to be "stretched," almost elliptical, along the primary's diffraction ring. The pair is not equally bright with the companion noticeably dimmer.

The thing that struck me about 32 Ori is it really gave the impression of a cosmic diamond ring. If it needs a moniker, it's "The Diamond Ring Double" for sure.

Edit: larger image.

Edited by Asbytec (11/11/12 08:23 AM)


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WRAK
Pooh-Bah


Reged: 02/18/12

Loc: Vienna, Austria, Europe
Re: 32 Orionis new [Re: Asbytec]
      #5513985 - 11/11/12 04:31 AM

Something is curious here: With 150mm aperture you have a radius of the Airy disk of about 0.92" and the radius of the first ring would then be about 1.5". According to WDS the current separation is 1.2" and the magnitude of the components is +4.4/5.8mag. So the companion should sit in between the spurious disk and the first diffraction ring of the primary giving an image rather of an hour glass instead of a diamond ring.
Wilfried


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Asbytec
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Reged: 08/08/07

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Re: 32 Orionis new [Re: WRAK]
      #5513989 - 11/11/12 04:40 AM

Wilfred, I trust your math, and so you should be correct. But, I do see it pretty much on the primary's first ring to within my ability to discern anything different.

I also sketched the companion;s first ring a little smaller. Not sure if that would be correct, either. I know color might have an affect, but it did not appear to be a very distinct color different from the companion. Maybe it was. But, It did appear smaller, if only an illusion. It requires another look.

Are you sure the radius of the first ring is that large? I thought it was closer to 1.2", but cannot remember (if I ever knew for sure.) Actually, this is the very star that prompted me to wonder about the diameter of my 6" Mak's first ring so I could better estimate separations.

Lemme look at the math for diffraction patterns and see if I can find the math that will give the proper radius. Thanks for pointing that out, I had not looked into it in a while.

Edited by Asbytec (11/11/12 05:32 AM)


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Asbytec
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Reged: 08/08/07

Loc: La Union, PI
Re: 32 Orionis new [Re: Asbytec]
      #5514036 - 11/11/12 07:05 AM

Indeed, if the first minimum is 1.22 lambda/D = .92", then the second maximum is 1.63 lambda/D ~ 1.2".

Rayleigh limit: 1.22 * 550 * 0.206/Dmm = resolution " arc, of course for the Airy disc.

Second maximum a = 1.63 Lambda/D
1.63 * 550 * 0.206 = 184.68/150mm = 1.23" arc

Edited by Asbytec (11/11/12 08:19 AM)


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Astrodj
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Reged: 08/24/11

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Re: 32 Orionis new [Re: Asbytec]
      #5525035 - 11/17/12 08:25 PM

Along with some other doubles, I observed this double for the first time last night with my 10" Dob.

I was able to see both components cleanly separated by a thin black line at 300X.

Flowery colors you say, Jim? I'll say gardinia white for the primary, pale white rose for the secondary.

Edited by Astrodj (11/17/12 08:25 PM)


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Astrodj
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Reged: 08/24/11

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Re: 32 Orionis new [Re: Astrodj]
      #5525038 - 11/17/12 08:27 PM

Nice skectch of the diamond ring effect, Norme. I don't often have good enough seeing to see diffraction rings but I saw a similar effect last night.

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Asbytec
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Reged: 08/08/07

Loc: La Union, PI
Re: 32 Orionis new [Re: Astrodj]
      #5525107 - 11/17/12 09:09 PM

DJ, again, well done. You got color! It eluded me.

Glancing back at the sketch, I realize for some reason the companion's rings are inside the primary's first minimum. That's a mistake, I thought I blacked them out.

But, you know, seeing was so good during that observation, I actually did try to see the companion's rings inside (as shown.) I failed, not even sure the laws of diffraction will permit it. The companion's ring just seemed to hover outside the primary's ring.


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Astrodj
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Re: 32 Orionis new [Re: Asbytec]
      #5525401 - 11/18/12 01:28 AM

Quote:


Glancing back at the sketch, I realize for some reason the companion's rings are inside the primary's first minimum. That's a mistake, I thought I blacked them out.

But, you know, seeing was so good during that observation, I actually did try to see the companion's rings inside (as shown.) I failed, not even sure the laws of diffraction will permit it. The companion's ring just seemed to hover outside the primary's ring.




Ah, I didn't pick up on that in your drawing until you pointed it out. I'm sure some here know if that is possible or not.


All I saw was one faint diffraction ring from the primary star, stabilizing for several seconds then dissolving for a few, then coming back. Great seeing for my locale, but far from perfect.

I envy your sketching abilities (along with all the other sketch contributors to this forum). I don't think I will ever be able to come close. My drawings look silly, even to me!


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Asbytec
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Reged: 08/08/07

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Re: 32 Orionis new [Re: Astrodj]
      #5525453 - 11/18/12 02:26 AM

Well, powerpoint can make nice dots and rings.

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azure1961p
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Reged: 01/17/09

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Re: 32 Orionis new [Re: Asbytec]
      #5533909 - 11/22/12 12:49 PM

I saw plain white for both last night with the 8. They showed best at 243x though 200x was good too. The six/ten Pickering made the diffraction rings often a garbled muddle but the spurious discs were seen frequently with a definite size difference and distinct, if delicate, line between them. I missed 72 Pegasus due to the late hour but after seeing how the seeing messed with 1.3" I knew 0.5" would've been for naught.

A side note that kinda shows how the seeing was for Jupiter last night is that E And F of the trap were both seen even at 140x though F would make long hiatuses in the shifting seeing and peaked out maybe 25% of the time. For giggled I out in 450x via the 4mm Abbe but it did nothing but highlight the disruption of the rings.

I'm off obviously and will be going out again tonight.

Pete


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Asbytec
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Reged: 08/08/07

Loc: La Union, PI
Re: 32 Orionis new [Re: azure1961p]
      #5533914 - 11/22/12 12:53 PM

Great, Pete, good to see your doing it.

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Sasa
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Reged: 11/03/10

Loc: Ricany, Czech Republic
Re: 32 Orionis new [Re: Asbytec]
      #5534141 - 11/22/12 04:04 PM

Norman, nice observation! I tried this double twice last year. One night I was successful in ED100 at 350x. Of course no dark space was visible between the components but the two stars were quite distinct. Without prior knowledge, I estimated PA~30deg and difference in brightness about 1 magnitude. The other night, I could not even glimpse it in 250mm Newton at 200x and 310x.

Funny enough, the very same nights, I was also observing 52 Ori. I could see it in ED100 only as undistinguished prolonged star while in N250 I could clearly separate the two components at 310x even with dark space between the componenst.


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Asbytec
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Reged: 08/08/07

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Re: 32 Orionis new [Re: Sasa]
      #5534378 - 11/22/12 07:52 PM

Sasa, it's nice to know you're enjoying these doubles, too. Thank you for reporting it.

That you noticed a magnitude difference in 32 Ori prompts me to look again. 52 Ori was like a diamond ring under 9/10 seeing. Both beautiful.


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azure1961p
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Re: 32 Orionis new [Re: azure1961p]
      #5536224 - 11/23/12 08:36 PM

Quote:

For giggled I out in 450x via the 4mm Abbe




Leave it to an Android autocorrect. Ill translate that: "For giggles I put in 450x via the 4mm Abbe"

Its special when I cant understand my own post.

Pete


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WRAK
Pooh-Bah


Reged: 02/18/12

Loc: Vienna, Austria, Europe
Re: 32 Orionis new [Re: azure1961p]
      #5536776 - 11/24/12 08:18 AM

If I ever get my current project (observing all doubles in my field of view over the year and within the reach of my 140mm refractor - will take several years) finished I too will start with sketching open clusters and doubles but I will do it the classic way means only by hand during observation.
Wilfried


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Asbytec
Guy in a furry hat
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Reged: 08/08/07

Loc: La Union, PI
Re: 32 Orionis new [Re: WRAK]
      #5537462 - 11/24/12 04:10 PM

Nice project, Wilfred. Right now, Jupiter is my passion and project, but always looking for something to do after a session with Jove. A nice double star project, maybe.

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Rutilus
Carpal Tunnel


Reged: 12/17/10

Re: 32 Orionis new [Re: Asbytec]
      #5539060 - 11/25/12 04:33 PM Attachment (30 downloads)

This is my sketch from 4 years ago. Scope used was 102mm f/8
refractor.


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azure1961p
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Reged: 01/17/09

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Re: 32 Orionis new [Re: Rutilus]
      #5539431 - 11/25/12 09:17 PM

That's very very nice Rut! Clean subtle gradient nicely done.

Pete


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Asbytec
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Reged: 08/08/07

Loc: La Union, PI
Re: 32 Orionis new [Re: Rutilus]
      #5539436 - 11/25/12 09:20 PM

Nice observation, looks beautiful. Does your sketch hint of a blue hue? It avoided me. Well done.

On the night above, Rut, the seeing was so dead calm, I tried to see if the companion's first ring could be seen inside the primary's first minimum (kind of like the sketch above, which is in error.) I failed to see it, and believe it's not possible, anyway. But, the seeing was so calm and I was so new to doubles, it was interesting to try.


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ziridava
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Reged: 08/17/12

Loc: Arad,Romania,Eastern Europe
Re: 32 Orionis new [Re: Asbytec]
      #5562022 - 12/09/12 08:59 AM

Last Monday ,at about 11 p.m.,I was trying to split 32 Ori with my 125mm F/7 Dobsonian.
The sky was foggy,a grey persistent veil covered all the sky,additionaly my observation was made through sucker holes.
I used 52 Ori to calibrate the focus.It was not a clean split of this fine double at 236x/7.5mm Celestron Plossl +2x Japanese ,,no name'' Balow lens.
Only at times I saw,for brief moments 52 Ori split ,,ala carte''.
At 32Ori,at 144x/Radian 6mm , ,,it was something'' in the image,but I coudn't tell to see a companion.
Moving to 236x magnification,I saw the stars as an ,,eight'' shape ,the companion well visible but no black space between them.The companion seemed to be ,,glued'' to the main star, being also considerably smaller and dimmer.
I estimated a position angle PA=30-40 degree,no colors were discernable.
At Eta Ori no significant result,apart the failure.
At the end of my session,I was trying to observe the Trapezium (hoping to see a Pentagono or maybe even an Exagoni) ,but no chance.
Actualy,this is the way as my Winter sky look most... of the rare occasions when there is some sort of clear sky.

Regards,Mircea


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