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Steve Gottlieb
August 12th, 2014, 02:12 AM
I haven't heard of this object until Jimi gave me a copy of this year's TSP Advanced Observer's list "Seeing Red" and I noticed something called the "Serpens Object, SVS 2". Of course, my curiosity was piqued and I placed it high on my observing list the first night observing at Lassen National Park last month with Jimi and others (Mark Johnston, Mark Wagner, Carter Scholz). The "Serpens Object" is a very red (continuum) reflection nebula illuminated by the pre-main sequence star [SVS76] Ser 2 = HBC 672. It is located within the core of the Serpens Molecular Cloud, a dusty star-forming region that includes several HH objects -- HH 458/459/478.

First I tracked down the nearby reflection nebula vdB 123, which I had observed a couple of times previously in my 18-inch. This reflection nebula was easily picked up at 175x and involves mag 9.8 HD 170634. The glow extends mainly northwest of the star (not seen to the south) in an oval shape 2'x1'. HD 170634 is collinear with three equally spaced double stars to the southwest! The closest pair is ∑2321 = 8.5/9.6 at 6", which lies 7' SW. In addition, ∑2324 = 9.0/9.4 at 2.4" lies 13' NE. The Serpens Object lies ~7' WNW, just west of the line connecting the double star ∑ 2321 and a mag 10.5 star 9' to its NNE.

This unusual Red Reflection Nebula was seen at 175x, knowing the exact position. It appeared extremely faint, small, round, ~15"-20" diameter. Using averted vision the glow popped ~20% of time, and was only seen for brief glimpses, though confirmed with certainty. Visually, there wasn't much to see, but it was still exciting to pick up such an obscure object.

Here are the coordinates if anyone wants to take a look and report back -- 18 29 56 +01 14 48 -- and here is the SDSS image (better quality in my full report at Adventures in Deep Space (http://www.astronomy-mall.com/Adventures.In.Deep.Space/Lassen%20Volcanic%20National%20Park.html))

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akarsh
August 12th, 2014, 03:05 AM
Hi Steve

I observed this object while going after the "Seeing Red" list with my 18" at this year's TSP. I'm pretty bad at logging, so this is all I have:

"At the edge of visibility. Another reflection nebula is nearby." and a vague sketch of what I saw. (TSP; 29th May 2014)

Steve Gottlieb
August 12th, 2014, 03:41 AM
Thanks, Akarsh, that's an excellent observation with an 18-inch. vdB 123, the nearby reflection nebula, seemed blazing to me in comparison to the Serpens Object.

akarsh
August 12th, 2014, 04:36 AM
Thanks, Akarsh, that's an excellent observation with an 18-inch. vdB 123, the nearby reflection nebula, seemed blazing to me in comparison to the Serpens Object.

Thank you Steve. I agree with you on the reflection nebula, both by interpreting my meagre logs and some vague fading memory. I detected the reflection nebula without knowledge of its existence -- it had to be bright! I remember that Parsamyan 21, which was also on the Seeing Red list, which I saw subsequently, was much much much brighter and easier in comparison.

Jim Chandler
August 12th, 2014, 05:03 AM
I observed the Serpens Object on November 1, 2013. Larry Mitchell was in Fort Davis, and we were working on the Seeing Red list. I pointed the 30" to the coordinates, popped in a UHC filter, and promptly saw an irregular nebula. Thinking "gee, that was easy", I consulted the eyepiece fov chart and realized the nebula was in the wrong place--it was vdB 123. Nearby, with the precise location known due to the chart and ultimately without the filter, the Serpens Object appeared as a "very dim glow 4' north of HD 170545" at 226x.

Steve Gottlieb
August 12th, 2014, 07:12 AM
Thanks, Jim. I had a feeling you probably looked at it -- and were one of the first to have ever viewed it! -- while checking out the visibility of the objects on the "Seeing Red" list. As you noted, it's a toughie.

Paul Alsing
August 13th, 2014, 12:21 AM
Hi Steve,

I observed this guy 8 or 9 years ago on a very nice night at CalStar, but I have it designated as Herbig-Haro 478A.

Here is what happened. In March 2004 Jay McNeil posted on amastro (message 12079) a list he had compiled entitled ***Small or Peculiar Nebulous Objects Thought to be Associated with Regions of Recent Star-Formation*** This is a very long list of very obscure objects. I proceeded to copy/paste the coordinates of each into Megastar and/or SkyTools and look at the DSS overlay in search of new potentially observable objects, a mostly dreary project. I popped the coodinates for "Nebula of unknown nature HHL62=GGD29 18 30 03.3 +01 16 20" and found a tiny little guy (probably unobservable) on the DSS, but in an interesting field. It was about 6' northwest of VdB 123, which I had never observed. It was also about 2' northeast of a brighter anonymous nebula, meaning that is was not in the database of either Megastar or SkyTools. A coordinate search in Simbad told me this was HH 478A.

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So, I made one of my library documents for the area, and the opportunity to view it with my 25" came up on that night at CalStar in the fall of maybe 2005. I remember that the Serpen's Object, although faint, was held with direct vision, and I was thrilled to see another H-H object, as these guys aren't the easiest things to view. VdB 123 was much brighter, of course, and the double stars in the area were also nice.

Maybe Jimi could look for the original object on Jay's list (coordinates above) :)

Steve Gottlieb
August 13th, 2014, 01:51 AM
Hi Steve, ...snip/snip...I popped the coodinates for "Nebula of unknown nature HHL62=GGD29 18 30 03.3 +01 16 20" and found a tiny little guy (probably unobservable) on the DSS, but in an interesting field. It was about 6' northwest of VdB 123, which I had never observed. It was also about 2' northeast of a brighter anonymous nebula, meaning that is was not in the database of either Megastar or SkyTools. A coordinate search in Simbad told me this was HH 478A...

Thanks, Paul, for your observation and the comment about Jay McNeil's original object HHL 62 = GGD 29. I looked it up in SIMBAD and I see the full name for GGD 29 is Gyulbudaghian-Glushkov-Denisyuk 29 (try saying that a few times in a row). Now, we're talking some pretty obscure YSO's!

Jimi Lowrey
August 14th, 2014, 02:26 AM
Paul I will try for the small nebula next time I get a clear dark night. It should be a fun challenge I'll post what I see here.