ASTRO: Sharpless 2-235

After Arp 157 I'm taking a short break from Arp galaxies to process some
other things I took last winter. Here are Sharpless 2-235 and PK
173.7+02.7. The first is an emission nebula while the latter is a
planetary nebula, at least it is so classified. They are located in the
constellation of Auriga, just north of M36 so you know I took them some
time ago and am just getting around to processing them. There's some
major confusion as to the identities of these objects. Even the
normally accurate SIMBAD seems to have some problems here. Best I can
determine SH2-235 is the large brilliant object that dominates the
center of my image. The planetary is the orange object below it.
However both SIMBAD and NED seem to think the planetary is SH2-235 and
give the odd name of [KC97c] G173.6+02.8 to the Sharpless object. Yet
Sharpless' description of 2-235 definitely identifies the big object as
being the right one. The planetary is also identified in some catalogs
as an HII emission nebula rather than a planetary. SIMBAD shows the
location of the planetary as a molecular cloud full of masers which are
microwave lasers often found in regions of star birth. This argues for
the HII classification though the odd orange color is rare in HII
regions but not unheard of. Also there are a lot of Herbig Haro objects
in the area. Again these are new stars not dying ones that a planetary
signifies. Looking for a Ph.D. thesis? Straightening this mess out
might be one.

SH2-234 is considered to be caused by the collision of two vast
molecular clouds. The collision has triggered a great amount of star
formation that is only seen in deep dust penetrating infra red light.
It is about 1800 parsecs (5900 light years) away by some estimates I
found. It is part of a much larger complex consisting of several far
larger Sharpless objects. All too big for my system. The faint H alpha
seen in the upper left corner is a very small part of SH2-232. Even
fainter tendrils from SH2-231 can be seen coming in from the right.
They, along with SH2-233 way off to the right of my image are all part
of the same complex. SH-2-235 is caused to glow by the brilliant 09
star near it core.

There's an asteroid in the image. It appears to be two lines on either
side of a star just of the NE (upper left) edge of SH-235 as if I'm
trying to point out the star. That's because I took 40 minutes of
luminosity data, then 60 minutes of color data followed by 40 more
minutes of luminosity and 30 more minutes of color data. Since the
color data made a mess of the star's color it was subtracted out during
processing. This makes the gap in the trail, which by coincidence
jumped the star. The asteroid is (51850) 2001 OJ92 at magnitude 18.5.

14" LX200R @ f/10, L=8x10' binned 2x2 RGB=3x10' binned 3x3, STL=11000XM,
Paramount ME

Rick
--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".

Beautiful image Rick. I did not know there was a blue reflection nebula
nearby.
I also doubt that the PN is really a PN as it appears to be too faint in
OIII to be one...

Stefan

"Rick Johnson" schrieb im Newsbeitrag
ster.com...
After Arp 157 I'm taking a short break from Arp galaxies to process some
other things I took last winter. Here are Sharpless 2-235 and PK
173.7+02.7. The first is an emission nebula while the latter is a
planetary nebula, at least it is so classified. They are located in the
constellation of Auriga, just north of M36 so you know I took them some
time ago and am just getting around to processing them. There's some
major confusion as to the identities of these objects. Even the
normally accurate SIMBAD seems to have some problems here. Best I can
determine SH2-235 is the large brilliant object that dominates the
center of my image. The planetary is the orange object below it.
However both SIMBAD and NED seem to think the planetary is SH2-235 and
give the odd name of [KC97c] G173.6+02.8 to the Sharpless object. Yet
Sharpless' description of 2-235 definitely identifies the big object as
being the right one. The planetary is also identified in some catalogs
as an HII emission nebula rather than a planetary. SIMBAD shows the
location of the planetary as a molecular cloud full of masers which are
microwave lasers often found in regions of star birth. This argues for
the HII classification though the odd orange color is rare in HII
regions but not unheard of. Also there are a lot of Herbig Haro objects
in the area. Again these are new stars not dying ones that a planetary
signifies. Looking for a Ph.D. thesis? Straightening this mess out
might be one.

SH2-234 is considered to be caused by the collision of two vast
molecular clouds. The collision has triggered a great amount of star
formation that is only seen in deep dust penetrating infra red light.
It is about 1800 parsecs (5900 light years) away by some estimates I
found. It is part of a much larger complex consisting of several far
larger Sharpless objects. All too big for my system. The faint H alpha
seen in the upper left corner is a very small part of SH2-232. Even
fainter tendrils from SH2-231 can be seen coming in from the right.
They, along with SH2-233 way off to the right of my image are all part
of the same complex. SH-2-235 is caused to glow by the brilliant 09
star near it core.

There's an asteroid in the image. It appears to be two lines on either
side of a star just of the NE (upper left) edge of SH-235 as if I'm
trying to point out the star. That's because I took 40 minutes of
luminosity data, then 60 minutes of color data followed by 40 more
minutes of luminosity and 30 more minutes of color data. Since the
color data made a mess of the star's color it was subtracted out during
processing. This makes the gap in the trail, which by coincidence
jumped the star. The asteroid is (51850) 2001 OJ92 at magnitude 18.5.

14" LX200R @ f/10, L=8x10' binned 2x2 RGB=3x10' binned 3x3, STL=11000XM,
Paramount ME

Rick
--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".