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Old 29-03-2010, 11:01 PM
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ngcles
The Observologist

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Join Date: Dec 2006
Location: Billimari, NSW Central West
Posts: 1,664
Observing Report NGCLes -- 19th March 2010

Hi All,

Our usual New Moon Saturday night, which would have been on the 13th March was a very cloudy night, so a few of us gathered for a couple of drinks and a yak. The previous month when we lost our regular night we went the following Friday and so we resolved again to try a Friday again. As per the previous month, we'd have a 4 day Moon that would set about 9.30 but we'll live with that okay.

Friday the 19th was warm and mostly cloudy day but the Bureau, the numerical weather and I all agreed it woud break in the hour or so before sunset -- fingers crossed. As it turned out that's exactly what happened, and we had clear skies all night except that I thought the transparency was a bit off -- there seened to be a weak high-haze and the sky was a fraction brighter than normal. That was backed-up by the SQM readings that at about 9pm showed 21.05 (ZLM +6.14) that slowly improved to 21.27 (ZLM +6.26) by 2am. The seeing slowly improved from a 6/10 early in the evening to 7/10 and I made notes of a total of 30 objects and observed many other old favs besides.

Mars was as underwhelming as usual -- small, strong polar cap, a bit of detail here and there. Saturn was much better than Mars -- really beautiful, but isn't it always?

A magnitude estimate of Eta Carinae put it at +4.6 -- a bit down on the last couple of of months.

In the main my recorded observations revolved around some galaxies in Hydra and then later on I spent quite a bit of time in the immediate surroundings of Omega Centauri (NGC 5139) -- there is a surprising amount to be seen here. Unfortunately I won't be able to share those observations with you because I'm hoping to turn them into a Deep Sky Delights article for AS&T about this time next year. So, if you want to read "Pt 2" of this report, you have to buy AS&T probably April next year.

The last recorded observation I made was of the Carina PNe NGC 2867 after PGC mentioned it in his report and we went on till about 2.20am when I was just getting too weary. I had been up since 7am and it's a 1 hr drive home.

Here are the observations:


x185 27'

IC 531 Galaxy *
RA: 09h 17m 50.8s Dec: -00° 16' 42"
Mag: 14.4 (P) S.B.: --- B-V: --- Size: 1.7'x0.5' Class: (R')SB(rs)ab?
P.A.: 60 Inclination: 6 R.V.: --- Source: RC3 *

This took a bit of time to track down and I'm not really sure why because it isn't that hard to see. Found imm to the S of a 13th mag * just off the N flank of the eg with another slightly fainter one beneath the E end of the S flank. The DSS shows it as a very thin, narrow pointed spindle but it doesn't quite look like that in the ep. More of a long oval, blunt-tipped oval, 1.25' x 15" in about PA 75, surface brightness is lowish but not too bad, grows broadly and weakly to centre without apparent zones, core or nucleus.



x185 27'
x247 20'

NGC 2850 Galaxy *
RA: 09h 20m 57.0s Dec: -04° 56' 22"
Mag: 15.1 S.B.: --- B-V: --- Size: 0.9'x0.7' Class: S0
P.A.: 31 Inclination: --- R.V.: --- Source: PGC *

This is a tiny faint eg no more than about 20" diameter. It has not unreasonable SB, low but not too bad -- just very small. 20" diameter, round growing from indefinite edges slightly to centre where there is a very faint stellaring almost verging on a star-like mag 16 nucleus.



x185 27'
x247 20'

IC 534 Galaxy *
RA: 09h 21m 15.4s Dec: +03° 09' 02"
Mag: 14.9 (P) S.B.: --- B-V: --- Size: 1.7'x0.2' Class: Sb
P.A.: 148 Inclination: 7 R.V.: +3517 Source: RC3 *

This is an extremely faint object only occasionally visible. It is pointed at by an asterism that resembles the 3 brightest *s in Aries and is just S of the * that would be Alpha (Hamal). A very tiny patch of occasionally visible gossamer, 20-odd arc-seconds across, no detail.



x185 27'

NGC 2861 Galaxy *
RA: 09h 23m 36.5s Dec: +02° 08' 11"
Mag: 13.5 (P) S.B.: --- B-V: --- Size: 1.5'x1.3' Class: SB(r)bc
P.A.: 155 Inclination: 1 R.V.: +5134 Source: RC3 *

This is no worse than mod faint. The eg forms the SE point in a five-of-diamonds, where the SW and NW points are wide pairs. The other stars are mags 10-12. The eg is easy to see, 1.5' to 1.75' diameter, grows mod and broadly to centre. Good SB and at times look just a bit grainy but no apparent core or nucleus. It has a mag 14 * just off the SE edge of the halo.



x185 27'

NGC 2864 Multi-Galaxy Sys *
RA: 09h 24m 15.4s Dec: +05° 56' 27"
Mag: 14.8 S.B.: --- B-V: --- Size: 0.8'x0.7' Class: Sc
P.A.: 14 Inclination: --- R.V.: +3546 Source: PGC *

This is a very tiny and faint eg found in the middle of a field where to its south is a small trapezium-style asterism not much bigger than the real thing made up by 10th, 11th and 12th mag *s. Really tiny, 15" diameter, an almost stellar-spot of haze with a very faint star -- 16th mag appended to the southern edge of the halo. Round.



x185 27'

NGC 2877 Galaxy *
RA: 09h 25m 47.0s Dec: +02° 13' 44"
Mag: 15.1 (P) S.B.: --- B-V: --- Size: 0.5'x0.4' Class: Pec
P.A.: 132 Inclination: --- R.V.: +6959 Source: RC3 *

NGC 2878 Galaxy *
RA: 09h 25m 47.6s Dec: +02° 05' 20"
Mag: 15.1 (P) S.B.: --- B-V: --- Size: 0.8'x0.2' Class: Sa:
P.A.: 174 Inclination: 6 R.V.: --- Source: RC3 *

These two are in adjoining fields -- -78 is to the S by about 12'. -77 Appears to the E by a few arc-mins from a trapezium-style asterism of 12-13th mag *s. Small and faint, round with consistent SB and possibly slightly elong in PA 0, maybe 30" x 20" growing slightly to the centre without zones or nucleus. -78 is almost identical, maybe just a fraction brighter or of higher S.B.



x185 27'

NGC 2881 Arp 275 Double Galaxy *
RA: 09h 25m 54.7s Dec: -11° 59' 45"
Mag: 14.1 S.B.: --- B-V: --- Size: 0.8'x0.6' Class: S?
P.A.: 21 Inclination: --- R.V.: +4221 Source: RC3 *

I had to find this eg by hopping from IC 2482 two fields to the SE -- the Argo may have an erroneous position for this one. The eg is round a little to the W of the bottom-stroke of an L shaped asterism made up by 10-12th mag *s. Curious looking. Doesn't look like an eg really. There is a mag 14.5 * just off the NE edge of the halo and seems to be weakly elong in PA 0. Lowish but consistent SB haze slightly oval 30" x 40" and occasionally looks vaguely mottled or blotchy.



x185 27'

NGC 2890 Galaxy *
RA: 09h 26m 29.6s Dec: -14° 31' 44"
Mag: 15.1 S.B.: --- B-V: --- Size: 0.8'x0.5' Class: E/S0
P.A.: 55 Inclination: --- R.V.: --- Source: PGC *

This eg is found to the SW by 5' from a mag 8/12 pair in PA 180. At first glance it looks stellar, but close scrutiny shows a tiny faint halo 15" x 10" in PA 30 growing slightly to centre where there is a very faint stellaring that dominates it. Quit faint. Not easy to see.



x185 27' x247 20'

NGC 2897 Galaxy *
RA: 09h 29m 45.7s Dec: +02° 12' 25"
Mag: 15.9 S.B.: --- B-V: --- Size: 0.7'x0.4' Class: S0
P.A.: 170 Inclination: --- R.V.: --- Source: PGC *

NGC 2898 Galaxy *
RA: 09h 29m 46.5s Dec: +02° 03' 50"
Mag: 14.4 (P) S.B.: --- B-V: --- Size: 1.0'x0.7' Class: S0+ pec:
P.A.: 125 Inclination: --- R.V.: --- Source: RC3 *

These two eg are in a pair, 8' apart N-S with -97 at the N, lying 2' W of a very, very distracting 8th mag *. -97 is a very, very faint eg no more than 20" diameter, round with consistent very low SB, perhaps grows weakly to centre.

-98 is 8' S of -97. Brighter of the pair, more like 30" diameter and round growing without zones, broadly and slightly to centre where there occasionally seems to be a very faint stellaring.



x185 27' x247 20' x317 15', x371 13' UHC & OIII

NGC 5307 Planetary Nebula *
RA: 13h 51m 03.4s Dec: -51° 12' 24"
Mag: 12.1 (P) Size: 22.0" Class: 3 Mag C. Star: 14.6 Source: Str-ESO *

Probably best with the UHC an interesting PNe with some odd features. About 20" across and elong in about PA 0, annular but not in the normal form. There are two brightest portions that are mirror opposed apostrophe-comma on the E & W sides -- they are like a ', or more like the old screen-gems logo:

http://a3.twimg.com/profile_images/8...ogo_bigger.png

but without the central dot. The SW one might be a little brighter. Centre not completely dark and no sign of the central star. Best at x317.

x185 27' x247 20' x317 15' x464 9' OIII & UHC

NGC 2867 Henize 2-27 Planetary Nebula *
RA: 09h 21m 25.4sDec: -58° 18' 43"
Mag: 9.7 (P) Size: 24.0" Class: 4 Mag C. Star: 16.6
R.V.: --- Source: Str-ESO *

Impressive object with a strong cyan tint comparable to the Blue Planetary (NGC 3819) in Centaurus & a few others. Good conditions allowed me to apply a fair bit of magnification (with UHC & OIII x317, x371 & x464 -- though the latter was a bit soft looking) The inner disc seems about 12" diameter and round with a very hard edge to it. It dims weakly to centre but at centre (or nearly so) I suspect there is a very, very tiny (<1" dia) much darker hole or dot -- looking like a pin-hole. Surrounding the inner-disc is a thin very LSB outer halo only 10-15% larger than the inner halo -- say almost 15" diameter that is very tenuous. Beautiful field.

Best,

Les D

Last edited by ngcles; 30-03-2010 at 04:00 PM.
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