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morsie
June 19th, 2020, 07:23 PM
I've put this on my "to do" list. Not discovered until 2005 the Necklace Planetary Nebula in Sagitta is a relatively bright (10.6) apparent magnitude. Its size is approx 13". I'm amazed that this escaped discovery until 2005.... but space is a big place(:> I've included a location map. Start with star Beta Sagettae as your begin point.

Matt391939203921

Steve Gottlieb
June 20th, 2020, 03:25 AM
I viewed this object back in 2011 with Jimi Lowrey through his 48-inch soon after it was announced as a new planetary nebula (https://watermark.silverchair.com/mnras0410-1349.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_ 9Cf3qfKAc485ysgAAAqkwggKlBgkqhkiG9w0BBwagggKWMIICk gIBADCCAosGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMoRE OORrIdgmeXPK-AgEQgIICXC4ARmqN1OIKPz08Nt-zOzMMD1bCXjMCkOhzYk3ejqTEWtojO9Zu5GUKm_DMCxEVL5BG8 QUu9ZlAjaynVPHZOaklzIj2weaUFlmRfTNj0GI2AuHzMDwx9xQ Gzp3w2j2Yx3H_c_hFGP_7gpUgwY8PjFc_MfSs8_mVHPLwuKUaT c5BvR8TWIxsvjBx8IIsBBBVkETxTjIRq5854BxAyQAe5BuM3aO oOEEZqNIdJBiGXJAmrIr0wzRmrXJFBMV3ZVSStUGWbBLY4Eve3 WVFDxDAtda4CMHP5gbPv_K2SyRNnVTAmsl3IiQ7qy-cPkz_ZhVxF5BuQhq7exysfzIZKv8h-y6ObonKilacR2BgDuy-n6gFbXxu4kP4otiR81viD8zs-4S2eWum0fEgSr48MK0n1jF5MoXBiasc9dh_rayg2BiGmWUX9zc baA0bZIx5_H4wJ_Fk3O-UgoDreB8bdIJX1u11mX3jPIa0_BVsbuABwJkONBYLQkbacLgBh JaPHp3ENK-7eSmUDefw4NQ4CEj46OfDdfLojGBEUOHrPN-VPLfp_3uVxBVmIaVdoMs2n57veIBSjrAaI07FogIoFLTOxwdvT b-k2rdX0ieMSTwCtCAHyzec88RajHVpWSFRVGcHl86rFPA4Qx-nKvUUk-SskCNZU0vV93qNJ-8chd7Zzwzo7DdDO8XmDDUPzRwsuVoa4YnFg4dpDrf48LVbrv4D BCwwsSB0CCfsBTfz1p-B9WEaRyDH_EJCq8bUS6O2YkKZsCWwHnMZhXU6L9gHzMI9UBsyy ve46GwtuZwza80).

48" (10/22/11): I was surprised this new planetary was easily picked up with direct vision at 488x as a faint, fairly small, oval glow with an irregular surface brightness. The outline was slightly elongated WNW-ESE, ~20"x15", and a mag 14.5 star is close off the SE end. The nebula was mottled in spots and brighter along the north to west portion of the rim. With careful viewing the NW end of the planetary resolved into a couple of faint, extremely small knots with one directly at the NW end that was easily seen.

Here's the position if others want to give a try. It's certainly one of the brightest IPHAS (Isaac Newton Telescope Photometric H-alpha Survey) planetaries, though is much fainter than mag 10.6.

RA: 19 43 59.5
Dec: +17 09 01

Jimi Lowrey
June 20th, 2020, 12:36 PM
I have observed The Necklace many time since its announcement. I distinctly remember one observation on a night with excellent seeing at 813X the ring of knots was resolved and the nebula looked like a oblong diamond necklace. The knots on this night were direct vision. This observation is burned into my memory.

Uwe Glahn
June 20th, 2020, 01:58 PM
Spectacular object indeed. I could also resolve some knots with my 27-inch under very good seeing. Always worth a visit.

sketch: 27", 977x, NELM 6m5+, Seeing II
3922
Necklace Nebula (http://www.deepsky-visuell.de/Zeichnungen/IPHASXJ194359.5+170901.htm)

Mark SW
June 20th, 2020, 02:50 PM
Steve,
I tried your link but it does not work for me.
Thank you
Mark

This might be the one.
https://academic.oup.com/mnras/article/410/2/1349/1032856#86161346

I realize I probably wont be able to see it. I am going to try Abell 62(PK 47-4.1) NGC 6804 and 6803 tonight so might just try.

morsie
June 20th, 2020, 05:45 PM
Steve,
What is the apparent mag then? Is that published somewhere? Thanks in advance. I may not be able to see it with a 22" in eastern seaboard skies but I'm going to try.

Steve Gottlieb
June 20th, 2020, 06:52 PM
Yes, that's the correct link. The arXiv preprint is here (https://arxiv.org/pdf/1009.1043.pdf).

Steve Gottlieb
June 20th, 2020, 07:25 PM
Unfortunately, it's very unlikely there's a published apparent magnitude. You might find a photographic estimate, but that's a very poor guide to the visual appearance.

Because the light is emitted at discrete wavelengths, computing a reasonably accurate magnitude (for any planetary) involves integrating (summing) the published flux measurements at its various emission lines. This has been done for bright PNe, but not for many obscure ones like the Necklace.

So, the best technique is simply to take a look and see if it's visible!

morsie
June 20th, 2020, 08:34 PM
Great sketch Uwe! Do you print the star field and then sketch the object? Or, do you sketch everything? Ether way, the end result is top notch.

morsie
October 20th, 2020, 09:21 PM
I finally saw the Necklace from home in eastern West Virginia in SQM 20.8 skies a couple of weeks ago. Very small oval and mottled at 450x. I did see a few of the gas knots. This was with a 22" scope. Thanks to all who commented on this object.

akarsh
October 27th, 2020, 06:32 AM
This is very exciting. I "discovered" the Necklace recently and added it to my observing list, but it's a bit late in the season now (right?), so I never got to go after it. Hopefully, in the spring!

Clear Skies!

akarsh
June 14th, 2021, 07:29 PM
I finally got around to seeing the Necklace. In my 18" telescope on a night of good seeing, the nebula was very faint and slightly elongated. It responded strongly to an OIII filter. I could not see any detail with the OIII.