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Old 13-04-2008, 05:57 PM
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The Observologist

ngcles is offline
Join Date: Dec 2006
Location: Billimari, NSW Central West
Posts: 1,585
30 hrs in Heaven -- Observing report Mudgee Star Party NGCLes (Pt 4)

Pt 4 ...

x185 27' TF

IC 3188 Galaxy *
RA: 12h 20m 55.1s Dec: +11° 00' 32"
Mag: 15.3 (P) S.B.: --- B-V: ---
Size: 0.6'x0.4' Class: S? P.A.: 41
Inclination: --- R.V.: +5402

This is a very small and faint round eg found to the SE of a mag 10 * by 5', rising broadly and slightly to centre without apparent nucleus. Very faint and of LSB.

x185 27' TF

IC 3170 Galaxy *
RA: 12h 20m 26.7s Dec: +09° 25' 30"
Mag: 14.9 S.B.: --- B-V: ---
Size: 0.4'x0.4' Class: Sbc(s)I-II P.A.: ---
Inclination: --- R.V.: ---

This is a very very faint and tiny round eg almost looking stellar. No more than 10-15" diameter rising somewhat to centre and no stars immediately associated.

x185 27' TF

NGC 4316 Galaxy *
RA: 12h 22m 42.8s Dec: +09° 19' 56"
Mag: 13.6 (B) S.B.: --- B-V: ---
Size: 2.4'x0.4' Class: Scd? P.A.: 113
Inclination: 7 R.V.: +1262 Source: RC3 *

This is a lovely though very faint little splinter of haze in PA 120. Mod low SB about 2.25' x 10" growing slightly and broadly to the axis nr centre with no apparent core or nucleus. A mags 14/14 pair is near the W tip on axis.

x185 27' TF

IC 782 Galaxy *
RA: 12h 21m 37.0s Dec: +05° 45' 56"
Mag: 14.5 S.B.: --- B-V: ---
Size: 1.6'x0.8' Class: SB0/SBa(r)
P.A.: 65 Inclination: --- R.V.: --- Source: PGC *

This is a very tiny pretty faint eg that is immediately N of a mag 12 * and appears no more than 20" diameter rising moderately and evenly to centre. Pretty faint.

x185 27' TF

NGC 4294 Galaxy *
RA: 12h 21m 17.8s Dec: +11° 30' 36"
Mag: 12.5 (B) S.B.: 13.4 B-V: +0.45
Size: 3.2'x1.2' Class: SB(s)cd
P.A.: 155 Inclination: 6 R.V.: +421 Source: RC3 *

NGC 4299 Galaxy *
RA: 12h 21m 40.9s Dec: +11° 30' 07"
Mag: 12.9 (B) S.B.: --- B-V: +0.40
Size: 1.7'x1.5' Class: SAB(s)dm:
P.A.: 26 Inclination: --- R.V.: +209 Source: RC3 *

This is a quite nice pair of eg found to the NW of a "V" shaped asterism of mags 11 -13 *s. -94 is to the W and is elong in PA 160 as a lowish SB eg of pretty consistent SB about 2.25' x 20" - a long ellipse of faint haze with a mag 15 * at the NW tip. -99 is immediately E by 2.5' and is a pretty diffuse LSB patch of haze about 1.25' diameter rising broadly and slightly to centre without apparent core or nucleus.

x185 27' TF

IC 3199 Galaxy *
RA: 12h 21m 45.6s Dec: +10° 35' 43"
Mag: 14.9 S.B.: --- B-V: ---
Size: 1.0'x0.6' Class: S
P.A.: 6 Inclination: --- R.V.: --- Source: PGC

This is a very small and faint eg that makes a RA triangle with 2 *s to the N and NE a of mags 12 and 14 a few arc-mins distant. Very small and quite faint it is round and rises slightly to centre where there is a somewhat brighter spot that dominates it. Overall 20" diameter.

x185 27' TF

NGC 4307 Multi-Galaxy Sys *
RA: 12h 22m 05.8s Dec: +09° 02' 39"
Mag: 12.8 (B) S.B.: --- B-V: ---
Size: 3.6'x0.7' class: Sb sp P.A.: 24
Inclination: 6 R.V.: +1134 Source: RC3 *

IC 3211 Galaxy *
RA: 12h 22m 07.3s Dec: +08° 59' 25"
Mag: 15.1 (P) S.B.: --- B-V: ---
Size: 0.8'x0.6' Class: Sd P.A.: 114
Inclination: 1 R.V.: +5971 Source: RC3 *

NGC 4307 is a really lovely LSB spindle shaped eg about 3' x 15" in PA 160 with faint tips but well-defined flanks and containing a small slightly brighter streak-like core/nucleus. -94 is to the S by 3' and it is a very tiny spot of very faint haze about 15" diameter with no central brightening.

And that concluded recorded observing for the night at about 2.35am with the last SQM reading I took at 2am showing 21.74 = ZLM +6.48. We continued observing until nearly 4.30am which included many winter Milky Way objects, paying attention in particular to G.Cs in Sagittarius. We also took a bit of a look at a wobbly Jupiter but the seeing wasn’t much chop and the image at x185 wasn’t that pleasing.

Climbing into bed at almost 5am I was wearing a very contented look as I snuggled down into my new goose-down sleeping bag that had me feeling warm as toast in seconds despite the fact that the temperature was hovering over 0 deg C.
___________________________________ __________________________________

We slept late the next morning and after brekky tripped into Mudgee for a bit of a walk around, a Kebab at the Kebab shop in the Wollies Mall and to pick up some perishable foods for the next few days. We took our time and wandered back at about 3pm (we forgot Peter Ward’s talk was on – D’oh) and spent the afternoon relaxing under a bright blue sky.

After an early dinner, I headed up to the bus-park and prepared everything before spending a bit of time up at the top shed enjoying happy hour, a cleansing ale and a few nibbles.

Not a cloud in sight, I re-started observing at 8.00pm but struck my only glitch for the weekend: After starting the first object, the voice recorder said it was full and refused to record further observations. A quick check showed that somehow it had been switched on to Stereo HQ sound recording and last nights 90mins worth was all it would take. So no recorded observations for the Friday night.

I took an SQM reading out of interest at about 9.30pm which showed 21.84 – WOW!!

The soundtrack for the evening included: Ummagumma: Pink Floyd, Hyperborea and Force Majeure: Tangerine Dream, Five Miles Out & Ommadawn: Mike Oldfield, and then Star’s End: David Bedford.

I spent most of the early evening in the southern sky and we had quite a few visitors drop down for a look through by my and Gary’s ‘scope. We looked at a lot of showpieces like: the Horsehead (Barnard 33 & IC 434), M42, M104, NGC 4038-39, the Eta Carinae complex (NGC 3372), the Tarantula (NGC 2070), NGC 5189, and all the globulars of the far southern sky.

IC 2531 is one of my very favourite spots in the sky, a really spectacular and faint exactly edge-on barred spiral that considering its distance, must be an extremely massive galaxy. An image is here:

And of course NGC 2997 (the emblem of the Sutherland Society is equally stunning and shows clear spiral arms in conditions like this. An image is here:

About midnight, some thin fog rolled in that lasted for about an hour and we ended up inventing a game to play with the laser-pointers that basically amounted to follow-the-leader as about 6 of us from all over the property skipped from star to star following one leader. An onlooker much have thought some LGM had landed near Mudgee!

It cleared-off about 1.30am and at about 2.30am young Damien Clarke who had been observing up top near the shed with John’s big 16” dob called “Tweety” came down and claimed that he had found something near Gamma Corvi that wasn’t on his maps. To be honest I was pretty sceptical at first and he wasn't able with any certainty to pinpoint its location. Damien went back up for a while and came back with his own 8" dob and quickly found it a short distance from Gamma Corvi.

I took a look through his 'scope and it took me completely by surprise -- it was a pretty big (maybe 8 arc-mins diameter or larger) nebulous object, probably about 10th magnitude with a weakly brighter zone/spot in the centre. Then went over to my own 18" and within seconds had it in the field and Thought I saw a weak greenish hue in the centre -- it certainly looked like a comet. The Argo Navis gave me an almost pinpoint RA and Dec and a search on Megastar with Realsky showed there was definitely no known object at that position -- certainly none that matched the appearance. I also displayed the known comets -- none. This is how it looked at x85:

A large, maybe 8-10' diameter round patch of weak milky haze rising from very indistinct edges slightly to centre where there is a small weakly brighter, about 40" diameter core-zone but no real pseudo nucleus. Inner regions seem to have a weakly lime hue.

I usually download and install the orbital elements of new comets if it looks likely to be bright and it didn't fit my additions -- excitement was building. It had to be a comet, the only question was whether it was already known.

The next step was to go to the internet to check for other known comets using the MPC data -- a visit up to the shed to log on proved a big frustration -- the net positively refused _point blank_ to connect (don't ya just love dial-up??) whatever we did.

I tried waking-up a couple of people (Gordon Garrad, Steve Quirk) that could help without success. I knew Rob McNaught wouldn’t be available (in Ilford for the SPSP), so no point making that call and with time passing on (now about 4.30am) there was only one alternative -- ring Brian Marsden at the IAU.

I made the phone call at 4.35am and gave the accurate position we had determined firstly using the Argo and refined to almost arc-second accuracy using Megastar. Silence for nearly a minute then ...

We got the same news -- Damien had re-discovered 2007 W1 -- just like you guys! Disappointment! ... but it was exciting while it lasted. We turned in about 5am again and it was still clear.

Pt 5 to follow ...
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