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Old 25-05-2008, 11:17 AM
你B
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Obs report 25/5

The main objective last night was to view Jupiter, hoping for a view that I got the night before. It didn't take long for me to realise, that the seeing, despite every scenario being as good as freaking possible, was completely and utterly crap. Only in Melbourne. Infact, it is typical of this area to have crud seeing in perfect setups. Just another fantastic trait of our desirable climate, ontop of the 180 annual cloudy days. I knew the seeing was crap just by observing stars as they were flaring, jumping and were being smeared everywhere. Every clear night this winter so far, seeing seems to be horrendous. My best viewings were in summer. I know many like to say that best seeing occurs in winter. A big fat LOL to that. Not in Melbourne. It is not by accident that everyone bags our climate.

Not only that, at one point I was also interrupted by (unforcasted - typical) Melbourne cloud, but luckily that cleared after around 45 minutes.

Anyway, to the point. I set up the 12" dob at around 8.30pm and waited 2 hours for cool down while watching Wife Swap and Everybody Loves Raymond. Set up was a bit late and 2 hours wouldn't be enough for a dinner plate sized, 1.5 inch thick chunk of glass. The plan was to observe some open clusters and globulars while Jupiter rises, that'll also give the mirror a chance to cool down properly. Just a random selection of objects.

Scope: 12" F4.65 truss dob
Time: 10:30pm-1:45am
Seeing: 2-3/10
Temp: 6慢

Harvard 6
Plotted as an open cluster in Musca in the HB atlas. Not alot could be seen at its plotted location. At 172x I could see 6 faint stars arranged in a cross with few others sprinkled about.

Harvard 8
Another alleged open cluster in Musca. All that could be seen at the supposed location is a diamond of 4 faint stars. There's nothing here to differentiate a would-be cluster from the background field. However, a short distance (2 FOVs at 172x) north lies a tiny trapezium of 4 stars with a further 6 arranged in a flattened "v" shape nearby. Maybe this is the real Harvard 8? Plotting error in the HB atlas perhaps?

LOD 757
Near the border of Musca and Centaurus lies this loose gathering. At 83x, I could see a line of 4 bright stars with a compact but sparse group of approx 15 fainter members located just to the north. Doesn't really stand out from the background field.

Rup 107
172x - same area of LOD 757, just a small faint loosely spread group of around 20 faint stars.

M20 - Trifid nebula
At 83x with the UHC filter I could just see the lanes, not bad considering the moon was just spitting distance away.

M8-Lagoon nebula
Again at 83x with the UHC, looked washed out for obvious reasons but could see a nice dark ribbon cutting across the nebula which made for quite a nice looking object. The brighter portion containing the Hourglass Nebula stood out well.

NGC 6153
This is a Planetary nebula located west of Zeta Scorpii. Crap seeing meant I couldn't use high mags. At 217x with UHC, it appeared as an egg-shaped patch of light, quite large aswell and I suspected annularity - which appears to be confirmed on photos. Showed up quite well despite moon glare. Forms a diamond with 3 adjacent bright stars.

NGC 6388
Globular cluster in Scorpius. At 217x (max possible on this night) there was no resolution although I could see 3 stars in its outer extremities, not sure if these were forground stars or actual cluster members.

NGC 6541
Another Scorpius globular. At 217x, it was largely resolved, perhaps 6/8th of the way in with 3 stars shining through the hazy, mottled core. Doesn't appear to have a tight condensed core. Very nice cluster, stood up well to the seeing. Infact it is one of the best globulars I've seen, after 47Tuc, Omega Cen, M22, the one in Pavo and the other one in Ara. Very nice and the background starfield makes it all the more nice!!! Kicks the crap out of many M clusters Set in a nice rich field. Only need some good seeing to enjoy it fully.

M5
217x - seems to go suddenly from tenious outer regions to dense inner region. Almost fully resolved, innermost region appearing granular with a stellar core. I'd actually say that this cluster is no better than NGC 6541, although is perhaps a bit larger.

NGC 6210
Planetary nebula in Hercules. Very low down, but had it at 172x, with UHC. Appeared as a blue orb, but seeing really was crud and couldnt make out any features.

Jupiter
Long awaited, unfortunately seeing sucked majorly. At 172x, no fine detail at all could be seen. Just the 2 main belts and 2 others. WHen I defocused the planet slightly, I marvelled at just how severe the 'boiling' was.

Last edited by 你B; 25-05-2008 at 12:56 PM.
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Old 25-05-2008, 01:04 PM
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goober (Doug)
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Some nice stuff there, SAB, shame about the seeing. I've been done with the flu for a week, which kills any interest in getting the scope out. I did step out last night to admire Jupiter and the moon a couple of degrees apart. Seeing looked steady to the naked eye - couldn't see any twinkle in Crux or Carina overhead. Berwick must be a local hot spot of turbulence!
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Old 25-05-2008, 01:18 PM
Karlsson
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Good report - always enjoy reading them

I checked the position of Harvard 8 (=Collinder 268) in various sources against your description: you may well be right... The correct position of the cluster is about 7' NNW of the one commonly listed - but the trapezium is not part of it, that's a tad too far North...
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Old 25-05-2008, 01:22 PM
你B
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I couldn't percieve much twinkling either but don't let that fool you! There's no explanation for near the ground turbulance, seeing as it was perfectly still. It was almost certainly high level turbulance.
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Old 25-05-2008, 05:09 PM
你B
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Quote:
Originally Posted by Karlsson View Post
Good report - always enjoy reading them

I checked the position of Harvard 8 (=Collinder 268) in various sources against your description: you may well be right... The correct position of the cluster is about 7' NNW of the one commonly listed - but the trapezium is not part of it, that's a tad too far North...
Thanks Karlsson. That's an interesting find, does confirm my thoery in a way Then, could Harvard 8 be that flat V shaped group I saw? That is located south of the trapezium, so it matches the position you describe.
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Old 25-05-2008, 07:06 PM
Karlsson
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Sab,

Attached is a DSS image of 40x40 arcminutes superimposed in CdC - North is up. The image is centered on the DSS (and Lyng) position of Harvard 8 (208, the lower red circle), but as you can see the actual cluster is in the upper red circle: the corrected position for Harvard 8/Collinder 268 as listed in Wilton Dias' database. If I read your report correctly your 'trapezium' is visible NNW of there - so you can check for yourself.

In general I have found Dias' data the most reliable when it comes to finding obscure OC's, and I use a CdC catalogue based on his list to prepare my maps.
Attached Thumbnails
Click for full-size image (Harvard 8.jpg)
189.5 KB13 views

Last edited by Karlsson; 25-05-2008 at 08:13 PM.
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Old 25-05-2008, 08:38 PM
你B
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Thanks for the link karlsson that does clear it up a lot. You can see the diamond I reported on the left edge of the '208' circle.

The Collinder 268 Circle contains the trapezium and the flat 'V' I saw. So that is the actual Harvard 8 then. When I was at the eyepiece, I noted that these features were "more impressive" than the stuff at the plotted position of the cluster so I figured something was amiss.
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Old 26-05-2008, 10:42 AM
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I've been finding Jupiter by far the best in the early mornings (6:30-7am). The atmosphere has settled right down by then, & there is less glare from the planet against the brighter morning sky. And of course, if the scope has been out all night then it is right on ambient..
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Old 26-05-2008, 10:58 AM
你B
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problem is that by then, Jupiter will be right over my roof, which will no doubt ruin the view and the 8-9 hours of dew would've swept the telescope away.
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