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Old 24-06-2009, 10:14 AM
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Observing Report - Saturday 20th June 2009;

Observing Report for Observing conducted Saturday 20th June 2009;

http://southernsentinel.co.nz/Observ...B-09-06-20.htm

Enjoy.
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Old 24-06-2009, 03:29 PM
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Toooooo fast

Hi Paul,

A great report as usual. I still think you observe tooooo fast. 56 objects in 150 minutes? Do you drive a car like that too?

Re NGC 5846, yes there are superimposed galaxies. Here is my observations of the field with 31cm at x186 almost 10 years ago:

x186 26' TF. NGC 5850, NGC 5846, NGC 5846A (PGC 53930), NGC 5845, NGC 5839, NGC 5838 and NGC 5831, appear in the same or adjacent fields.

NGC 5850 Mag 10.7 Size 4.3' x 4'. I will attempt to attack this group from E-W. The two major eg'sare -50 and -46. -50 this is a quite LSB obejct for magnitude 10. There are a couple of mag 13 *s just off the N edge of the halo. Perhaps 3' diameter, round LSB moderately bright much smaller round 30" diameter core which is not clearly detached from the halo rising further to an indefinite faint *ar type spot in the centre.

NGC 5846 Mag 10.0 Size 3.5' x 3.5'.About 10' WNW of -50, considerably higher S.B, about the same size 2.75' diameter rising in the outer halo slightly to the centre. Round. Nearer the centre a little more strongly. Substantially brighter round core/nucleus. NGC -5846A is superimposed 2/3 of the way out of the halo on the S.

NGC 5846A (PGC 53930) Mag 13.8 Size 0.4' x 0.3'. 2/3rds of the way out in the halo of NGC 5846 is this eg, appears as a seperate condensation within the halo of the above, perhaps 15" diameter rising strongly to the centre.

NGC 5845 Mag 12.5 Size 0.8' x 0.5'. A fairly LSB object, not large 30" diameter with a probable superimposition * dead centre or a *ar nucleus of mag 13. W by 10' further is -39.

NGC 5839 Mag 13.7v Size 1.3' x 1.1'. Just N of a mag 13*, 10' W of -45. Slightly elongated in PA 135, 30" x 20", fairly dim rises slightly to the centre without apparent core or nucleus.

NGC 5838 Mag 11.9b Size 4.1' x 1.4'. Found NW of the -46 group by 50'. Quite pretty. N by 5' from a mag 8 * which has a fainter companion. Very bright core, faint halo in PA 45, lenticular outline, 2.5' x 40", nearly round core in PA 45 rises evenly and strongly to centre where there is a non *ar nucleus.

NGC 5831 Mag 11.5 Size 2' x 1.7'. SW of the -46 group by 70'. Moderately bright little chap, 10' NW of a mag 10 * by 10', rises broadly and moderately to the centre azonally, with a hint of a *ar nucleus.
__________________

The NGC 5846/50 group got a guernsey in the Deep Sky Delights column for the May/June 2008 (last year) where the above raw observations was suplimented by some 46cm observations


NGC 5746 is very much a fav of mine -- lovely crack-like dark lane.

Interested to see you successfully observed NGC 6164-65 -- Glen Cozens to note!! (He asked this question not long ago about whether it is/would be visible in 12")

Love NGC 6445 too! Glad to see you saw it.

Good report. It brings back to my mind fond memories of when I used to be able to see the stars for myself. This generally very cloudy weather over Eastern Australia we've endured for months on end is getting me down!


Best,

Les D
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Old 24-06-2009, 06:16 PM
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Les,

I am slowing down!! Same amount of objects in double the time this time!! I should do some eyepiece swapping, that will give me a better appreciation for what I am observing.

I just love hopping round and the Argo Navis just gets me movin'.

Thanks for reading the report.
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Old 24-06-2009, 06:19 PM
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Les,

I could not see Ton 2. It's eluded me for years. One of those Hartung objects that bugs me.
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Old 24-06-2009, 08:10 PM
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Testing Ton Two

Hi Paul,

Quote:
Originally Posted by Sentinel View Post
I could not see Ton 2. It's eluded me for years. One of those Hartung objects that bugs me.
I'm not for a moment pretending that Ton 2 is easy -- it isn't. There is a certain knack to seeing so many of the difficult non-NGC GCs. Actually it's not so much a knack as a "paradigm" -- I think the keys to success are:

1st rule: Don't look for a GC. The traditional mental pic of a GC is a hindrance. Pretend you are looking for a small late type (ie Sc or Sd) face on spiral eg. No stars, no central condensation just a round smudge of weak gossamer.

2nd rule: (and this would appear particularly applicable to you) -- slow down. Be patient. You will probably need a several minutes at the ep before detection.

3nd rule: use some magnification -- use an eyepiece that approximately gives a 2mm exit pupil for best contrast on small LSB objects

I have seen it in my old 25cm under a mag 6.4 sky with eyes that were more than a decade younger -- very, very difficult though in that size. It is a little easier in 31cm. Once you've seen it once it's easier the next time.

25cm obs: x181 17' TF. Mag 12.24 Size 25.8" This cluster is found 7-7.5' to the NW of mag 4.5 Q Scorpii. This must be excluded to permit detection. Extremely !! faint in this apeture, barely there but largish, 2.5' -3' diameter as a weak patch of diaphanous gossamer with no central brightening. Mag 13 * superimposed in the WSW near the edge. Round. Confirmed by G Mitchell.

46cm: x247 20' TF can be held steadily with averted vision though it is hardly bigger, has an even surface brightness halo and shows no sign of resolution.

Find mag 4.3 q Scorpii in the tail of the Scorpion. 10' WNW of this star is an 8th mag star. Pick the mid-point between these two and it is just a few ac-mins north of the mid-point.

Try, try, try again!


Best

Les D
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Old 25-06-2009, 07:12 AM
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Thanks for the advice, Les.
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