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Old 08-03-2016, 06:09 PM
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ngcles
The Observologist

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Join Date: Dec 2006
Location: Billimari, NSW Central West
Posts: 1,543
Observations of AGC 3574, 8 March 2016

Hi All,

Had a fun session under the stars last night that I spent testing some new equipment, doing a bit of favourite spotting and lastly, in taking up the Pepsi challenge from a friend who is not part of this forum to observe Abell Galaxy Cluster 3574 in Centaurus.

One of the (many) nice things about living in a virtually pristine deep-sky site is that you have no real time-pressure to finish up an object (s) and move on, there's always another night. I spent the best part of an hour sleuthing-out this cluster that lies around the 200 million light-year mark and is fairly close-by to the bright, detailed Messier 83. There was one galaxy I had some trouble identifying, while it is plainly visible on the DSS, it was apparently passed-over by those who compiled the better-known galaxy catalogues and was identified by way of inquiry on SIMBAD (have I ever mentioned how much I hate the SIMBAD interface) rather prosaically as 6dFGS gJ134806.5-303205 -- presumably from the 6dF survey at compiled at Siding Spring using the UK Schmidt.

Anyway, here are the notes from about 1.30am 08032016. The SQM-L reading at the commencement of these observations was 21.91 mags/Sq arcsec, I rated the seeing at 6/10. The eyepieces used were 12mm TII Nagler and 9mm Nagler, x185 27' TF and x247 20' TF respectively.

AGC 3574 Galaxy Cluster
RA: 13h 49m 12.0s Dec: -30 17' 00"
Mag10: 13.0 (V) Mag3: 11.8 (V) Mag1: 11.4 (V) Size: 56.0'
Class: 0 1 I # Galaxies: 31 Source: RCG


IC 4329 Galaxy *
RA: 13h 49m 05.3s Dec: -30 17' 45"
Mag: 12.2 (B) S.B.: 13.9 B-V: +0.90 Size: 3.5'x2.2'
Class: SAB(s)0- P.A.: 63 Inclination: --- R.V.: +4527 Source: RC3 *

This is the central and brightest member of AGC 3574. Is a mod bright eg easy to see probably 1.25-1.5' diameter slightly elong in PA 90(?) growing slightly and broadly to centre and at centre is a not well defined, small, weakly brighter core containing a faint stellaring. Diffuse edged halo. -29A is 3' E.

IC 4329A (ESO 445-50) (PGC 49051) Multi-Galaxy Sys *
RA: 13h 49m 19.3s Dec: -30 18' 33"
Mag: 13.0 (V) S.B.: 12.0 B-V: +0.97 Size: 2.6'x0.7'
Class: SA0+: sp P.A.: 50 Inclination: --- R.V.: +4793 Source: RC3 *

A small mod faint spindle with slightly lower SB that -29 in about PA 60, probably 1' x 15" growing to the axis near centre and appear to have an occasional stellaring nr centre.

NGC 5298 Galaxy *
RA: 13h 48m 36.4s Dec: -30 25' 43"
Mag: 13.0 (V) S.B.: 13.1 B-V: +0.88 Size: 1.9'x0.8' Class: SB(r)b
P.A.: 73 Inclination: --- R.V.: +4412 Source: RC3 *

Is about 11' SSW of IC 4329 and part of a group including NGC 5302 that forms a rough square 6' a side. -98. Mod faint eg lying in a small triangle of 13th and 2 14th mag *s, seems elong in about PA 60 1' x 30", growing broadly and slightly to centre without apparent zones or nucleus. -302 is 6' SSE.

NGC 5302 Galaxy *
RA: 13h 48m 49.5s Dec: -30 30' 42"
Mag: 12.0 (V) S.B.: 13.1 B-V: +1.00 Size: 1.9'x1.1' Class: SB(s)0+:
P.A.: 159 Inclination: --- R.V.: +3549 Source: RC3 *

This eg has an oval outline 1.25 x 50" in about PA 150 rising broadly and weakly at first and then near centre, moderately to a small core zone and an occasionally *ar nucleus at centre. It has a mag 14 * off the W flank by 1'.

ESO 445-35 (PGC 48950) Galaxy *
RA: 13h 48m 11.1s Dec: -30 27' 07"
Mag: 14.0 (P) S.B.: --- B-V: --- Size: 1.3'x1.0' Class: SB(rs)b P.A.: 166
Inclination: --- R.V.: +4899 Source: RC3 *

is 6' W of -298 and found in a small rectangle of mags 14 & 15 *s small, 40" diameter, round, and lower SB than the two nearby NGC egs, mod faint, growing weakly to centre where there is a small slightly brighter zone and a suspected stellaring core/nucleus.

MCG -5-33-9 (PGC 48955) Galaxy *
RA: 13h 48m 14.7s Dec: -30 33' 03"
Mag: 14.9 S.B.: --- B-V: --- Size: 0.9'x0.8' Class: L
P.A.: 173 Inclination: --- R.V.: +5237 Source: PGC *

ESO 445-37 (PGC 48956) Galaxy *
RA: 13h 48m 15.9s Dec: -30 34' 30"
Mag: 15.3 (P) S.B.: --- B-V: --- Size: 0.8'x0.3' Class: S?
P.A.: 62 Inclination: --- R.V.: +4238 Source: RC3 *

6dFGS gJ134806.5-303205
RA 13 48 06.544 Dec -30 32 04.69
Mag 14.94 B

MCG -5-33-9, 6dFGS gJ134806.5-303205 and ESO 445-37 are at the south western and fourth corner of the 6' x 6' square with the above 3 egs. The first two are very similar looking very small spots of gossamer about 20-30" diameter with no structure visible. ESO 445-37 is a tiny sliver of featureless gossamer in PA 60 30 x 5" with a highly distracting 13th magnitude * immediately off the NW flank. Took a little time to pick this one up. Very, very faint

ESO 445-44 (PGC 49018) Galaxy *
RA: 13h 49m 00.6s Dec: -30 37' 30"
Mag: 15.0 S.B.: --- B-V: --- Size: 0.8'x0.8' Class: Sb
P.A.: --- Inclination: --- R.V.: --- Source: PGC *

This eg is about 7' S of -302 and is a very, very faint spot that at first looks like a 15th mag * but at x247 is revealed as a small, 30" diameter spot of gossamer with a mag 14.5 - 15 * embedded in the eastern halo. Really only barely detectable because of VV LSB.

NGC 5291 Multi-Galaxy Sys *
RA: 13h 47m 24.5s Dec: -30 24' 30"
Mag: 15.1 (P) S.B.: --- B-V: --- Size: 1.3'x0.9' Class: E pec:
P.A.: 157 Inclination: --- R.V.: +4340 Source: RC3 *

Is about 20' SW of IC 4329 and a little E of a pair of mags 10 & 11 *s. Mod faint, lowish SB round spot 30-40" diameter growing slightly to centre with no apparent core or nucleus.

NGC 5304 Galaxy *
RA: 13h 50m 01.5s Dec: -30 34' 42"
Mag: 13.6 (P) S.B.: --- B-V: --- Size: 1.4'x0.9' Class: E+ pec:
P.A.: 157 Inclination: --- R.V.: +3730 Source: RC3 *

Is about 20' SE of IC 4329 is a mod faint eg and close to a small almost perfect Eq tri of mag 14 *s a little of 1' a side. Small, 30-40" diameter, growing broadly and mod to centre but does not appear to contain any core or nucleus. Continuing that line from IC 4329 through -5304 and continuing another 20-odd arc mins is ESO 445-57.

ESO 445-57 (PGC 49180) Galaxy *
RA: 13h 51m 09.2s Dec: -30 46' 52"
Mag: 14.0 (P) S.B.: --- B-V: --- Size: 1.1'x0.8' Class: SB?
P.A.: 123 Inclination: --- R.V.: +5641 Source: RC3 *

Small spot about 20" diameter 2' NW of a 10th mag *, very LSB consistent SB spot about 20" diameter with no structure visible.

ESO 445-60 Galaxy *
RA: 13h 51m 45.2s Dec: -30 38' 03"
Mag: 15.6 S.B.: --- B-V: --- Size: 1.1'x0.3' Class: S
P.A.: 83 Inclination: --- R.V.: --- Source: PGC *

Is about 35' SE of IC 4329 and a few arc mins E of a 10th mag * and is a quite difficult and fain eg, 20 x 10" in PA 90 of consistent SB gossamer only intermittently visible with concentration. No structure. About 7' N of this is the pairing of ESO 445-59 and -59A.

ESO 445-59 (PGC 49208) Galaxy *
RA: 13h 51m 39.4s Dec: -30 29' 18"
Mag: 13.4 (B) S.B.: 14.3 B-V: +1.03 Size: 1.0'x0.5' Class: E?
P.A.: 111 Inclination: --- R.V.: +4550 Source: RC3 *

ESO 445-59A (PGC 49211) Multi-Galaxy Sys *
RA: 13h 51m 41.1s Dec: -30 30' 06"
Mag: 14.9 S.B.: --- B-V: --- Size: 1.2'x1.1' Class:
P.A.: --- Inclination: --- R.V.: --- Source: PGC *

These two eg are N-S of each other only about 1' apart and are both about 20-30" diameter, round spots of gossamer with no structure visible. -59 is probably slightly larger and marginally brighter.

ESO 445-56 (PGC 49162) Galaxy *
RA: 13h 50m 53.6s Dec: -30 17' 20"
Mag: 14.6 S.B.: --- B-V: --- Size: 1.2'x0.4' Class: S0
P.A.: 130 Inclination: --- R.V.: --- Source: PGC *

Is about 20' due E of IC 4329 and situated a little E of the mag 12* that makes the RA, in a small RA tri of *s mags 10, 10 & 12. A thin sliver of faint and very LSB, very elong 50" x 10" and no visible structure.

IC 4327 Galaxy *
RA: 13h 48m 43.8s Dec: -30 13' 03"
Mag: 13.9 (V) S.B.: --- B-V: +0.61 Size: 1.2'x0.6' Class: SB(s)c?
P.A.: 56 Inclination: --- R.V.: +5415 Source: RC3 *

Tis eg is found to the NW of IC 4329 by about 7' and nearby to a 10th mag distracting star to its W. Quite faint, small and elong 40" x 10" slash of gossamer with no apparent core or nucleus.

Best & Clear Skies,

Les D
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