DG 187

[Daniel_Sp]

Hello everybody!
Two month ago, a friend sent me an email with coordinates to DG 187 with his photo attached. In the Uranometria, no entry was set at the given position. Altough, I gave it a try in the same night. I observed at a power of 421x with a 24" dobson. I could simlpy see the bipolar structure of the reflection nebula. Here is my sketch:
1873

kind regards
Daniel

[Howard B]

Hi Daniel, can you pass on the coordinates of DG 187? Looks like a cool object.

Howard

[Steve Gottlieb]

Daniel, can you give us more information on this reflection nebula (also known as LBN 437)? Lynds gave a size of 75' x 20', but the SIMBAD position appears poor (~ 22 32.2 +40 35).

(I see Howard just posted the same question)

[Uwe Glahn]

Nice observation and sketch Daniel, on my list for next new moon.

I think Daniel mean the RN "GN 22.32.5". The DG number refers at a bigger object like Steve said. SIMBAD said RA 22 34 41, DEC +40 40 0. Should fit Daniel?

[Paul Alsing]

Daniel, can you give us more information on this reflection nebula (also known as LBN 437)? Lynds gave a size of 75' x 20', but the SIMBAD position appears poor (~ 22 32.2 +40 35).

(I see Howard just posted the same question)


The star pattern in Daniel's sketch matches exactly the reflcetion nebula around V375 Lacerta (LKHA 233) @ 22 34 41.014 +40 40 04.52, itself embedded in the much larger Sh 2-126. Simbad shows this to be an Herbig Ae/Be star, a pre-main-sequence star – a young (<10Myr) star of spectral types A or B (from Wiki). See this, from Simbad...

http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=V375+Lac&submit=SIMBAD+search

... and click on the supplied photo to get a larger FOV, which can be zoomed out to include the entire Sharpless object.. Note that Simbad gives several different designation for V375 Lac, but DG 187 isn't among them.

SkyTools does not have any designation for V375 Lac, but I have a doc for it, here...

https://docs.google.com/viewer?a=v&pid=sites&srcid=cG5hbHNpbmcuY29tfHd3d3xneDoxNzY2ZGRlMDY1ZjYz MWZh

There are a couple of double stars in the area, one easy and one not so easy.

[Jimi Lowrey]

Well I am now really confused. The object in Paul's Doc also is in a galaxy catalog as MRK 914?

[Daniel_Sp]

Hi,
yes - LBN 437 = GN 22.32.5 is only a bright reflection nebula within a large dark nebula complex. The coordinates were already given by Uwe.
@ Steve: I think, the size of 75' x 20' refers to the whole complex. LBN 437 is about 1' large.

CS, Daniel

[Clear Skies]

Daniel is correct, the size noted by Steve is for the larger complex: a curved lane of dark nebulosity with the reflection nebula on its SE edge.

Dorschner-Gurtler 187 = Lynds 437 = Bernes 35, also incorrectly designated as a galaxy and as such catalogued as PGC69208 = Markarian 914. Surrounding the variable star V375 Lacertae.

POSS2 Blue 75' here: http://archive.stsci.edu/cgi-bin/dss_search?v=poss2ukstu_blue&r=22+34+41.04&d=%2B40+40+03.6&e=J2000&h=75&w=75&f=gif&c=none&fov=NONE&v3=
30' here: http://archive.stsci.edu/cgi-bin/dss_search?v=poss2ukstu_blue&r=22+34+41.04&d=%2B40+40+03.6&e=J2000&h=30&w=30&f=gif&c=none&fov=NONE&v3=

SIMBAD links:
V375 Lac http://simbad.u-strasbg.fr/simbad/sim-id?Ident=v375+lac&NbIdent=1&Radius=2&Radius.unit=arcmin&submit=submit+id
DG 187 / LBN 437 http://simbad.u-strasbg.fr/simbad/sim-id?Ident=dg187&NbIdent=1&Radius=2&Radius.unit=arcmin&submit=submit+id
[B77] 35 http://simbad.u-strasbg.fr/simbad/sim-id?Ident=%5Bb77%5D+35&NbIdent=1&Radius=2&Radius.unit=arcmin&submit=submit+id
Mrk 914 http://simbad.u-strasbg.fr/simbad/sim-id?Ident=mrk+914&NbIdent=1&Radius=2&Radius.unit=arcmin&submit=submit+id

On NED:
http://ned.ipac.caltech.edu/cgi-bin/objsearch?objname=V0375+Lac&extend=no&hconst=73&omegam=0.27&omegav=0.73&corr_z=1&out_csys=Equatorial&out_equinox=J2000.0&obj_sort=RA+or+Longitude&of=pre_text&zv_breaker=30000.0&list_limit=5&img_stamp=YES

The reflection nebula is surprisingly bright and I could easily pick it up (using AV and my 12" SCT) as a small, very faint glow west of V375 Lacertae (179x / 27'). Both a UHC and H-Beta nebula blocked the light, OIII allowed it to pass but did not enhance the view. Rated 3/10 the first time I ran into it, 2/10 the night after.
6' NNW is the double star hj1786 / Couteau 1838 (WDS22345+4046).

Cheers,


Victor

[Uwe Glahn]

I revisited the object and thanks again Daniel for the tip. Absolutely cool object, also for a no so fan of galactic nebulae.

27", 419x, NELM 6m5+, Seeing III
1929

[Daniel_Sp]

Hey Uwe,
I saw your sketch already on your homepage. Great observation! You definetively have better conditions than I have in the "far north"...

Merry Christmas
Daniel