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Old 21-05-2010, 07:38 PM
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Paddy (Patrick)
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Dear all,

Here are some notes from last night. Whilst waiting for the glow of the recently set moon to fade, I visited some galaxies near Eta Arae (as recommended by Sab) and then some DSOs around Theta Ohiuchi. There is so much to see here that I never made it to the northern galaxies I'd planned to observe. But it was very good fun. Thanks for reading.

Seeing 5/5
Transparency 7/7

NGC 6221 GX in Ara
Mag 9.9v

250X Face on spiral with distinct nucleus and NW-SE bar. 2 spiral arms, - one to NE and one to SW. The contrast is diminished due to observing though Milky Way stars. With averted vision, the dark space between the northern arm and the bar is clear. The southern arm is less distinct.

NGC 6215 GX in Ara
Mag 11.5v

250 X About 20’ away from NGC 6221, this one is both smaller and fainter with foreground star superimposed. Slightly irregular circle of haze. I have the impression of 2 spiral arms.

ESO 138-1 is also very close to 6221, but is hard to pick out from the little knots of Milky Way stars that abound here.

Messier 9/NGC 6333 GC in Ophiuchus
Mag 7.6v

250X GC with no central core, but a N-S spattering of stars across the centre and a few resolvable stars in small clumps that seem to float in front of the haze. These seem oriented N-S one to the east and one to the west of the centre of the GC. I have the impression that the cluster is somewhat triangular with its apex pointing north.

Messier 19/NGC6273 GC in Ophiuchus
Mag 6.7v

175X A distinctly oval shaped cluster, the long axis roughly N-S with a small central core. I note a dark band across the southern end of the cluster, single at the eastern end and splitting into 2 bands as it crossed to the west. Strands of haze and stars emerge from the main body of the cluster to the west and east, both curving to the north and looking a bit like the horns of Thor’s Helmet. Quite a number of resolvable stars across the oval haze of the GC. 250X shows the dark patches to be much more complex in shape. A very interesting GC. The central concentration seems more obvious at lower power.

NGC 6284 GC in Ophiuchus
Mag 8.9v

250X A short hop from Messier 19, this is much smaller, about 5’ some central concentration. No resolvable stars, but I have the impression of some darker patches in the cluster. Quite compact, but with some strands of haze emerging from the main body of the cluster.

NGC 6293 GC in Ophiuchus
Mag 8.2v

175X About the same size as 6284, with a more distinct core, but the core is somewhat triangular with its apex pointing south. A fainter haze surrounds this. I estimate 7’ dia. With averted vision, the outer parts of the GC seem a little square. It looks a little like looking down at a square pyramid.

NGC 6355 GC in Ophiuchus
Mag 9.7v

175X A fainter GC, looks more distant, few resolvable stars, which may well be foreground stars. Looks little more concentrated towards the southern end. I have the impression that it is slightly elongated NW-SE. Looks about 3’ across.

NGC 6369 PN in Ophiuchus “the Little Ghost”
Mag 11.4v

175X Beautiful round PN with distinct outer ring and dark centre, slightly reminiscent of a red blood cell. Slight bluish tinge. No central star. The rim seems to be slightly iridescent. 250X with UHC filter enhances the appearance of the rim and the bright grains that give it the iridescent appearance are also brighter. Seems to respond better to UHC than OIII.
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Old 21-05-2010, 08:31 PM
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Great Report Paddy! Sweet 5/5 seeing, lucky you, although transparency has been superior in recent times. Guess one can't have both, its one or the other. Did you notice a knot in NGC 6221 just north of the core? There appears to be something there within the northern arm, Steve Gottleib's NGC notes support this but it's not clear on images whether it's a HII region or simply a faint foreground star(s).

Nice and clear here tonight, just preparing the scope for a 1-2am start. Finally got the secondary collimation nailed not 5 minutes ago
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Old 22-05-2010, 05:47 PM
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Paddy (Patrick)
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Thanks Sab, I found NGC 6221 quite complex to look at, I think because its amongst a bit of foreground activity. I want to have a bit more of a look at this one and perhaps do some sketching, I'll get back to you on the knot.

Hope you have a good night - if you get your scope any better collimated, who knows what you'll be able to see. I'm going to try your trick with a dark headcloth for my next exploration of faint galaxies. I already use a towel over my head for solar observing, so it's just one more small step into the lunatic world of the obsessed observer. I already look like some kind of hybrid of a brown bear, a pile of washing and a red-eyed dalek on most observing nights.
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Old 23-05-2010, 12:43 PM
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Hi Paddy,

Great observing report -- very enjoyable. Yep M19 is quite oval elongated N-S and well resolved. Apparently this ellipticity is due to tidal interction with the core of the Milky Way that it passed recently (in context).

M9 is probably the least of the Messier Clusters in Ophiuchus but in a true dark sky with a large 'scope it is a rewarding object at moderate powers. Here's an observation I made of it in 2005 up at Mudgee on a night that was absolutely freezing in late June (it was minus 3 at the time) that includes LDN 173 that is adjacent.

x185 27' TF

One of the lesser Messier clusters in Ophiuchus, but none the less a splendid object which is well resolved. Seems to have lower CC -- perhaps 8-9 with a broad moderate concentration of stars toward the centre. It is partially to well resolved at x185 with perhaps over 100 mag 13 to threshold stars peppered over the face of the cluster which has a hazy grainy background. Appears perhaps 8-9' diameter. The two brightest resolved stars are 1/2 way out on the S side of the halo and in an apparent pair with a clump of fainter stars surrounding them. Overall seems round. There is a conspicuous large void of stars to the W and SW of the cluster which shows up better with low power -- this is B 64 or LDN 173.B 64

LDN 173Dark Nebula
RA: 17h 17m 19.2sDec: -18° 31' 03"
Mag: ---Size: 12.0'x8.0'Class: Co
Appears 20' to the W and SW as an irregular shaped large 15' x 15' void with almost no faint stars within it.

There are quite a few faint but interesting galaxies in Ara and you've really only scratched the surface. Unfortunately, very few have NGC designations and can be a bit daunting. NGC 6300 is a bright barred-spiral well worth a look. But personally, though it is not spectacular visually (barely visible in 12") the pair of ESO 138-29 & -30 that is sometimes known as the "Toadstool Galaxy" a fantastic interacting pair of galaxies where a ring-form spiral has been created by a small dwarf plunging through the heart of the other. One to see just so you can say you've seen it ...


Best,

Les D
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Old 23-05-2010, 05:43 PM
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Quote:
Originally Posted by Paddy View Post
Thanks Sab, I found NGC 6221 quite complex to look at, I think because its amongst a bit of foreground activity. I want to have a bit more of a look at this one and perhaps do some sketching, I'll get back to you on the knot.
It is a bit weird to find a nice bright galaxy among the milky way star fields of Ara. I was looking for something else the first time I swept it up..by accident..darn thing almost gave me a heart attack! But definately an excellent galaxy IMO. I should've investigated this knot last night when seeing permitted magnifications close to 800x, some reckless magnification would've revealed on the spot if its a foreground star or a diffuse HII region.


Quote:
Hope you have a good night - if you get your scope any better collimated, who knows what you'll be able to see. I'm going to try your trick with a dark headcloth for my next exploration of faint galaxies. I already use a towel over my head for solar observing, so it's just one more small step into the lunatic world of the obsessed observer. I already look like some kind of hybrid of a brown bear, a pile of washing and a red-eyed dalek on most observing nights.
lol reminds me of one story I read somewhere about a couple of guys observing on a hill near Brisbane with their dobs and using towels to block stray light. Apparently the cops pulled up as a member of the public called them to report a group of Taliban extremists aiming rocket launchers at the city
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Old 23-05-2010, 08:49 PM
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Paddy (Patrick)
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Quote:
Originally Posted by pgc hunter View Post
It is a bit weird to find a nice bright galaxy among the milky way star fields of Ara. I was looking for something else the first time I swept it up..by accident..darn thing almost gave me a heart attack! But definately an excellent galaxy IMO. I should've investigated this knot last night when seeing permitted magnifications close to 800x, some reckless magnification would've revealed on the spot if its a foreground star or a diffuse HII region.


lol reminds me of one story I read somewhere about a couple of guys observing on a hill near Brisbane with their dobs and using towels to block stray light. Apparently the cops pulled up as a member of the public called them to report a group of Taliban extremists aiming rocket launchers at the city
I had another look at NGC 6221 this morning. I reckon I could see a brighter area on the northern part of the galaxy. I'm not sure that I'd call it a knot - it looked more diffuse than that. But curious.

I'll clearly have to be careful what kind of cloth I use, although we don't get many passers by here and Newstead would be an unlikely target for rocket launchers.

Quote:
Originally Posted by ngcles View Post
Hi Paddy,

Great observing report -- very enjoyable. Yep M19 is quite oval elongated N-S and well resolved. Apparently this ellipticity is due to tidal interction with the core of the Milky Way that it passed recently (in context).

M9 is probably the least of the Messier Clusters in Ophiuchus but in a true dark sky with a large 'scope it is a rewarding object at moderate powers. Here's an observation I made of it in 2005 up at Mudgee on a night that was absolutely freezing in late June (it was minus 3 at the time) that includes LDN 173 that is adjacent.

x185 27' TF

One of the lesser Messier clusters in Ophiuchus, but none the less a splendid object which is well resolved. Seems to have lower CC -- perhaps 8-9 with a broad moderate concentration of stars toward the centre. It is partially to well resolved at x185 with perhaps over 100 mag 13 to threshold stars peppered over the face of the cluster which has a hazy grainy background. Appears perhaps 8-9' diameter. The two brightest resolved stars are 1/2 way out on the S side of the halo and in an apparent pair with a clump of fainter stars surrounding them. Overall seems round. There is a conspicuous large void of stars to the W and SW of the cluster which shows up better with low power -- this is B 64 or LDN 173.B 64

LDN 173Dark Nebula
RA: 17h 17m 19.2sDec: -18° 31' 03"
Mag: ---Size: 12.0'x8.0'Class: Co
Appears 20' to the W and SW as an irregular shaped large 15' x 15' void with almost no faint stars within it.

There are quite a few faint but interesting galaxies in Ara and you've really only scratched the surface. Unfortunately, very few have NGC designations and can be a bit daunting. NGC 6300 is a bright barred-spiral well worth a look. But personally, though it is not spectacular visually (barely visible in 12") the pair of ESO 138-29 & -30 that is sometimes known as the "Toadstool Galaxy" a fantastic interacting pair of galaxies where a ring-form spiral has been created by a small dwarf plunging through the heart of the other. One to see just so you can say you've seen it ...


Best,

Les D
Thanks, Les. I'll definitely chase those ones up.
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Old 24-05-2010, 08:03 AM
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kustard (Simon)
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Mmmmm, more to view and compare
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