A surprise Planetary in Scorpius

While observing last night, I was searching for the bug nebula (PK 349+1.1)
and I chanced across a "mini ring nebula" about 2 degrees SW from Lesath.
The closest thing I can find on my chart is NGC 6337, but it is reported as
mag. 14 and I could see it easily in my 12.5" but one of my obeserving
partners also got it in his 6" scope. That should not be possible with a
mag. 14 object, right? Can anyone shed any light? Is this another surface
brightness issue?

Anyway, whatever it is, it looks great with a little power (I was using
180x) and an OIII filter. Oh, and I also found the bug nebula (just north of
halfway on the line between Shaula and Mu Scorpii), which has a very unusual
shape to it for a planetary.

Paul Lawler wrote:
While observing last night, I was searching for the bug nebula (PK 349+1.1)
and I chanced across a "mini ring nebula" about 2 degrees SW from Lesath.
The closest thing I can find on my chart is NGC 6337, but it is reported as
mag. 14 and I could see it easily in my 12.5" but one of my obeserving
partners also got it in his 6" scope. That should not be possible with a
mag. 14 object, right? Can anyone shed any light? Is this another surface
brightness issue?

I think it's NGC 6337. Mag 14 sounds like it might be a photographic
magnitude. Steinicke's revised NGC has it at magnitude 12.3.

Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.txt

Paul Lawler wrote:
While observing last night, I was searching for the bug nebula (PK 349+1.1)
and I chanced across a "mini ring nebula" about 2 degrees SW from Lesath.
The closest thing I can find on my chart is NGC 6337, but it is reported as
mag. 14 and I could see it easily in my 12.5" but one of my obeserving
partners also got it in his 6" scope. That should not be possible with a
mag. 14 object, right? Can anyone shed any light? Is this another surface
brightness issue?

I think it's NGC 6337. Mag 14 sounds like it might be a photographic
magnitude. Steinicke's revised NGC has it at magnitude 12.3.

Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.txt

"Paul Lawler" wrote in message
ink.net...
While observing last night, I was searching for the bug nebula (PK
349+1.1)
and I chanced across a "mini ring nebula" about 2 degrees SW from Lesath.
The closest thing I can find on my chart is NGC 6337, but it is reported
as
mag. 14 and I could see it easily in my 12.5" but one of my obeserving
partners also got it in his 6" scope. That should not be possible with a
mag. 14 object, right? Can anyone shed any light? Is this another surface
brightness issue?


It might be a photographic magnitude, not uncommon for NGC objects in my
experience. If this is the case, the it's highly likely that the visual
magnitude is brighter. This is because the old photographic plates were
most sensitive towards the red light, but most planetaries are brighter
towards the green light where our eyes are also most sensitive under low
light conditions.

I just displayed a digitized sky survey image of the region, and it only
shows that object within a 1-degree field of view around that object. If
your location is correct, it was NGC 6337
--
Sincerely,
--- Dave

----------------------------------------------------------------------
A man is a god in ruins.
--- Duke Ellington
----------------------------------------------------------------------

"Paul Lawler" wrote in message
ink.net...
While observing last night, I was searching for the bug nebula (PK
349+1.1)
and I chanced across a "mini ring nebula" about 2 degrees SW from Lesath.
The closest thing I can find on my chart is NGC 6337, but it is reported
as
mag. 14 and I could see it easily in my 12.5" but one of my obeserving
partners also got it in his 6" scope. That should not be possible with a
mag. 14 object, right? Can anyone shed any light? Is this another surface
brightness issue?


It might be a photographic magnitude, not uncommon for NGC objects in my
experience. If this is the case, the it's highly likely that the visual
magnitude is brighter. This is because the old photographic plates were
most sensitive towards the red light, but most planetaries are brighter
towards the green light where our eyes are also most sensitive under low
light conditions.

I just displayed a digitized sky survey image of the region, and it only
shows that object within a 1-degree field of view around that object. If
your location is correct, it was NGC 6337
--
Sincerely,
--- Dave

----------------------------------------------------------------------
A man is a god in ruins.
--- Duke Ellington
----------------------------------------------------------------------

I believe it is ngc6337. I observed this one last night myself for the first
time and also thought that it resembled a fainter Ring Nebula. I picked this
object to observe from Sky Atlas 2000, hit the Goto button on my 8" Nexstar
GPS, and saw the "mini-Ring" in the eyepiece. I'd say that ngc 6337 is almost
certainly the object that you observed.

Clear, dark skies,
Jeff McAdams

I believe it is ngc6337. I observed this one last night myself for the first
time and also thought that it resembled a fainter Ring Nebula. I picked this
object to observe from Sky Atlas 2000, hit the Goto button on my 8" Nexstar
GPS, and saw the "mini-Ring" in the eyepiece. I'd say that ngc 6337 is almost
certainly the object that you observed.

Clear, dark skies,
Jeff McAdams

While observing last night, I was searching for the bug nebula (PK 349+1.1)
and I chanced across a "mini ring nebula" about 2 degrees SW from Lesath.
The closest thing I can find on my chart is NGC 6337, but it is reported as
mag. 14 and I could see it easily in my 12.5" but one of my obeserving
partners also got it in his 6" scope. That should not be possible with a
mag. 14 object, right? Can anyone shed any light? Is this another surface
brightness issue?

Based on your description of the object's position and appearance, NGC 6337 is
the best candidate. Megastar lists NGC 6337 with a photographic magnitude of
11.9. The NGC/IC Project site lists a Vmag. of 12.3. The central star is listed
as 14.9 magnitude in Megastar. NGC 6337 was discovered by John Herschel. The
Herschel objects (both Wm. and John) are typically visible in a 12.5-inch
aperture under reasonably dark skies.

Anyway, whatever it is, it looks great with a little power (I was using
180x) and an OIII filter. Oh, and I also found the bug nebula (just north of
halfway on the line between Shaula and Mu Scorpii), which has a very unusual
shape to it for a planetary.

There's a 12th magnitude star positioned just north of center in the nebula.
This is a foreground star that's sometimes mistaken for the central star of the
planetary. NGC 6337 is a fine object for moderate apertu
http://members.aol.com/billferris/n6337.html

Regards,

Bill Ferris
"Cosmic Voyage: The Online Resource for Amateur Astronomers"
URL: http://www.cosmic-voyage.net
=============
Email: Remove "ic" from .comic above to respond

While observing last night, I was searching for the bug nebula (PK 349+1.1)
and I chanced across a "mini ring nebula" about 2 degrees SW from Lesath.
The closest thing I can find on my chart is NGC 6337, but it is reported as
mag. 14 and I could see it easily in my 12.5" but one of my obeserving
partners also got it in his 6" scope. That should not be possible with a
mag. 14 object, right? Can anyone shed any light? Is this another surface
brightness issue?

Based on your description of the object's position and appearance, NGC 6337 is
the best candidate. Megastar lists NGC 6337 with a photographic magnitude of
11.9. The NGC/IC Project site lists a Vmag. of 12.3. The central star is listed
as 14.9 magnitude in Megastar. NGC 6337 was discovered by John Herschel. The
Herschel objects (both Wm. and John) are typically visible in a 12.5-inch
aperture under reasonably dark skies.

Anyway, whatever it is, it looks great with a little power (I was using
180x) and an OIII filter. Oh, and I also found the bug nebula (just north of
halfway on the line between Shaula and Mu Scorpii), which has a very unusual
shape to it for a planetary.

There's a 12th magnitude star positioned just north of center in the nebula.
This is a foreground star that's sometimes mistaken for the central star of the
planetary. NGC 6337 is a fine object for moderate apertu
http://members.aol.com/billferris/n6337.html

Regards,

Bill Ferris
"Cosmic Voyage: The Online Resource for Amateur Astronomers"
URL: http://www.cosmic-voyage.net
=============
Email: Remove "ic" from .comic above to respond

"Bill Ferris" wrote in message
...


There's a 12th magnitude star positioned just north of center in the
nebula.
This is a foreground star that's sometimes mistaken for the central star
of the
planetary. NGC 6337 is a fine object for moderate apertu
http://members.aol.com/billferris/n6337.html

Thanks Bill, after reading the replies to my post and looking at your
drawing, I'm very confident that NGC 6337 is what I observed.