21 replies to this topic

[Mel Bartels]

Bob Grossfield, Obs Dir Sunriver and Lynn Carroll, a highly experienced amateur, were with me. Bob also saw it immediately with the curve, it took Lynn two looks. There are no boundaries or edges: one must move the scope back and forth to 'shake it loose' then it can be studied. The M31 / M32 / M110 portion is drawn 'conceptually'.

 

Very exciting observation !!! Now, the race is on: how small of aperture is needed? BTW, M31 and M110 show nice detail in OIII - never thought to look before

 

[bphaneuf]

Saw this recently in a photograph.  Wasn't sure it was observable visually in amateur telescopes.  Should have know you'd see it Mel.   Off we go!

Well done as always, sir!  Clear skies and dry paper to you.

-b

[Astrojensen]

Hi Mel 

 

I believe you actually saw it before; at least part of it. There's quite a prominent brightening in approximately the right place in your sketch from 2021:

 

https://www.bbastrod...the 30 inch.jpg

 

I actually checked up on your drawings, the very moment I heard of the discovery of the O-III cloud, because I thought I recalled that you had made a drawing of it already. 

 

Herschel/ Hagen nebulae all over again.

 

 

Clear skies!

Thomas, Denmark

Edited by Astrojensen, 21 January 2023 - 02:51 PM.

[Daveatvt01]

Very cool!!

[Bob4BVM]

Hi Mel,

I agree with Thomas !  I also looked at that previous sketch (amazing work ! ) of yours and there it was, yes ?

So my question is- were you using the O-III for that drawing ??

 

For this observation i assume you tried popping the O-III in / out to compare and confirm it really is an O-III emission nebula ?   Pretty cool, thanks for pointing this out.  Can't wait to try it myself.

 

To close i would just say i am jealous of your clear sky on Jan.20...  down here in the valley it has been months of muck with the exception of the other day when we had a nice sunny afternoon, a clear sundown. Looked hopeful at long last with a good sky at sundown. So i rolled the binoscope out, did some tune-up, Went in for a quick bite, and came back out just in time for the clouds to roll in again.

... took the scope down under our typical light drizzle which continued rest of the night.  grrrr !    I really need to get over the mountains to your skies

 

Cheers

Bob

Edited by Bob4BVM, 21 January 2023 - 03:32 PM.

[j.gardavsky]

Hello Mel,

 

and congratulations on the Strottner-Drechsler-Sainty 1  OIII cloud, SE of M31 !

 

It is a big achievement,

JG

[Mel Bartels]

Yes, last night I tried with and without the OIII filter. The nebulous feature disappeared or became so faint that I didn't bother studying it when I removed the filter.

That I didn't do this earlier... conservatively I don't think I can say that I saw it back when. Maybe. 

I intend to study areas here and there for OIII clouds just as I do for IFN/galactic cirrus. Who knows?

Mel

[Special Ed]

Saw this recently in a photograph.  Wasn't sure it was observable visually in amateur telescopes.  Should have know you'd see it Mel.   

+1 on what Butch said.  When I saw the image with the Olll cloud, the first thing I thought was...I wonder if Mel has captured this.  

[Erik68]

"While it took six hours or more to photograph some of the .
Of [the nebulae], it only took six minutes .
to see them. "Johann Georg Hagen
(1847-1930) Director of the Specola Vaticana inRome,

 

.....It's been 100 years.....we have super-sensitive CCD sensors, but the saying is still current.....

 

[bphaneuf]

I’m going to try to see it tonight in the 24” if the clear skies and good transparency hold. Fingers crossed!!

[Mel Bartels]

Exceptional transparency! The view through the 16 inch was both easier (able to see the full extent in the 2 deg field) and harder (a little dimmer) compared to the 30 inch. I could see the cloud without the OIII filter - I've seen this a number of times before and showed it to others at the Oregon Star Party, calling it the Andromeda Shelf (not knowing that it is an OIII cloud though) The OIII filter made for a very nice view.

Zane says he saw this in his 14 inch f3 a couple of weeks ago.

 

 

While looking for OIII clouds near M33 (nothing seen), I came across more IFN/galactic cirrus.

 

 

Mel Bartels

[bphaneuf]

Hey Mel,

Tried last night with the 24, but wasn't able to see it, alas!  The transparency was good, but I wouldn't call it exceptional.  And Andromeda being pretty far NNW now it's moving toward the Charlotte light dome, so that may be a thing as well.  The sketches you just posted are very helpful.  It may be that I was too far out.  My impression was that the cloud sits well beyond 32 And, but you're showing it right between 32 & Nu.  I think I'll have to file that away for later in the year, though, as the target is just too far north now.  That's assuming, of course, that I'm capable of seeing it in terms of experience and capability.

Clear and exceptional skies to you!

-b

[Bob4BVM]

Exceptional transparency! The view through the 16 inch was both easier (able to see the full extent in the 2 deg field) and harder (a little dimmer) compared to the 30 inch. I could see the cloud without the OIII filter - I've seen this a number of times before and showed it to others at the Oregon Star Party, calling it the Andromeda Shelf (not knowing that it is an OIII cloud though) The OIII filter made for a very nice view.

Zane says he saw this in his 14 inch f3 a couple of weeks ago.

 

 

 

While looking for OIII clouds near M33 (nothing seen), I came across more IFN/galactic cirrus.

 

 

 

Mel Bartels

Thx for the additional sketch Mel.

Had the binos out last night , for the first clear night in months, hallelujah !

 

Tried for your OIII, but M31 was already too far NW and blocked by trees from where i set up.  Hoping for another good clear one tonight.  I will get out earlier before it gets too far NW. The sky here was also exceptional.

 

Worked on stuff to the east and south.  Couldn't resist it, i kept coming back to M42 area. The bino view of that was out of this world, so to speak. I cannot find the right words...

 

Maybe i can come up one of these nights

 

CS

Bob

Edited by Bob4BVM, 24 January 2023 - 02:05 PM.

[Erik68]

bphaneuf

 

In the case of such very large objects, it is the Etendue of the telescope, not its aperture, that plays the key role. This follows directly from Mel's last report.

 

 

On a recent clear night I observed M81 with a Lumicon Olll 3 gen. filter (refractor-152/760) power 25x, FOV 3.2*.I think I observed something there that could not be seen without the Olll.
Unfortunately, because of the rapid clouding, I was not able to do a precise revision, perhaps it was my imagination or some artefacts....
I am now waiting unsuccessfully for the weather.....
 

Edited by Erik68, 25 January 2023 - 04:44 AM.

[Mel Bartels]

--- I've experimented: these structures become largely invisible to me with exit pupils smaller than 5mm. I use exit pupils from 5-8mm (oversized pupils are effective - they do not waste light as the eye is filled with as much light as it can possibly take in given the eyepiece though not all the aperture contributes to the image, but then countless wasted photons litter the observing field).

 

--- Not true that these faint structures (OIII cloud, galactic cirrus) only show on very long digital images. Searching online, I find shorter exposure digital images that are not overly processed. Re-processing them reveals hints of these structures. Of course the images are grainy, not aesthetically pleasing and can be mistaken for optical and camera background effects.

 

--- My explanation of etendue:  https://www.bbastrod...er.html#etendue

--- How I use etendue in designing my telescopes: https://www.bbastrod...signer.html#HET

 

Mel Bartels

[Robin]

I'm very very impressed!! And I must confess that right after I learned about the discovery of this object I took a look at your website, Mel, because I remembered that you had an M31 + galactic cirrus sketch there.

 

How would you rate its difficulty compared to galactic cirrus such as the Mandel-Wilson objects?

 

Since you mentioned "nice OIII detail in M 31", did you observe the OIII jet emerging from somewhere near the galactic center of M 31? Such OIII jets can be seen on images of other galaxies, too, and I've wondered about their observability.

 

 

Clear skies,

Robin

[Mel Bartels]

Speaking of 'etendue', apparently a telescope is not needed at all. Jerry Oltion, editor at Sky and Telescope, Robert Assumendi, binocular telescope maker extraordinaire along with other club members were able to see the OIII cloud in filtered 80mm binocs at a dark sky site with exceptional transparency in Oregon.

 

The brightness is similar to the Mandel-Wilson IFN clouds. If you haven't seen the IFN yet, think of the Horsehead cloud. The OIII cloud is maybe a fraction, say, 1/4 to 1/2 as bright.

 

I saw unexpected OIII detail in M31 and M110. I aim to go back and nail it all down by sketching. I don't recall a jet emanating from the galaxy center, but will look for one.

 

Mel Bartels

Edited by Mel Bartels, 25 January 2023 - 05:30 PM.

[robertasumendi]

Here's my beautiful sketch lol. I think Jerry and I basically agreed about boundaries. We were fairly limited because I left my newer oiii filters at home so had to use one oiii and one uhc.

Attached Thumbnails

• 

Edited by robertasumendi, 25 January 2023 - 05:58 PM.

[Mel Bartels]

I find that a beautiful sketch, Robert. What a journey: to go from detecting in a 30 inch to 80mm binos within a few days. Deflating and exciting at the same time. I'd love to see this structure in a bigger binoscope for sure! Mel.

[robertasumendi]

Thanks Mel, no need to feel deflated. There's a really good article I found years ago that explains how this works: https://tinyurl.com/aww33prx Check out the colorful circle chart.

 

I think it's really interesting the way you clearly saw the two graceful long arcs as separate in the 30" but by 16" it has condensed in your sketch into a solid wedge shape, which is what I saw as well. I didn't really feel two separate arcs at all. One interesting thing (I intentionally didn't sketch) about having a UHC in one eye and an OIII in the other was seeing a bridge of hydrogen nebulosity from the galaxy to the OIII arc. 

 

Aside from the filter problem, the Moon was still out, plus the red sketching flashlight kept killing my night vision, plus this is just kind of the wrong time of year for M31 since it's so low. Looking forward to taking another whack at it. Would love to see a sketch from your 6".

 

Big sounds good!  

[Bob4BVM]

I find that a beautiful sketch, Robert. What a journey: to go from detecting in a 30 inch to 80mm binos within a few days. Deflating and exciting at the same time. I'd love to see this structure in a bigger binoscope for sure! Mel.

This is all so darn exciting !  Aside from two nights ago (which was beautiful, but i was late to catch M31 in a good position), I am still suffering in valley muck.

 

I skied at Hoodoo today til dark, sky was nice. Coming down the west slope to valley, it got all mucked up at around 2500 FASL.   Mel, Robert, is there a chance we can do a run this weekend ? Have large binoscope, will travel

 

... i suppose in another couple days Luna will put the kibosh on any attempts at the O-III region

 

Bob

Edited by Bob4BVM, 25 January 2023 - 11:24 PM.

[uwe_glahn]

Stunning result Mel.

 

I tried the cloud with my new 6" f/5 some days ago under very good transparency.
Unfortunately M 31 was low in the sky and I only could use my mid size EP (4,2mm) with filters.

 

Finally I could not clearly see the cloud. I tried 6nm and 12nm [OIII] filters.
With larger EP (6mm), field (4°) and without any filters I could spot a larger glow 0,5°-1,0° SW of nu And, but I classify it seeing the washed out denser star group in the area.