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Old 30-10-2018, 05:26 PM
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ngcles
The Observologist

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Join Date: Dec 2006
Location: Billimari, NSW Central West
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A few galaxy groups in Pisces including HCG 97 & 98

Hi All,

Some observations last night using Brontes (63.5cm f/5). The session started at 9.20pm and I concluded at 11.40pm about 20 minutes before moonrise just after midnight.

The Hickson 98 group was really quite pretty and some of its members pretty challenging.

Almost as soon as I had the 'scope ready to go last night, following a completely calm day a "nuisance value" northeaster sprang up making the seeing a bit poorer and vibrating the 'scope. Of course, the moment I wheeled it away at 11.40pm (about 20 minutes before moonrise) it stopped! The SQML reading at the start of the session (9.20pm) was 21.78 and at the conclusion at 11.35pm 21.90. Seeing varied from 6/10 at the start to 4/10 at the conclusion, with 5/10 most often. I actually covered a lot (+30) galaxies in Pisces most of which turned out to be small, faint and generally uninteresting -- however, these are the highlights:

x195 25' TF x260 19' TF
NGC 7783 (Arp 323) Hickson 98A Galaxy *
RA: 23h 54m 10.0s Dec: +00° 22' 59"
Mag: 14.0 (B) S.B.: --- B-V: --- Size: 1.1'x0.5' Class:
P.A.: 116 Inclination: --- R.V.: +7826 Source: RC3 *

MCG +0-60-59 Hickson 98B PGC 72808 Multi-Galaxy Sys *
RA: 23h 54m 12.0s Dec: +00° 22' 37"
Mag: 15.0 (B) S.B.: --- B-V: --- Size: 0.5'x0.4'
Class: E? P.A.: 165 Inclination: --- R.V.: +7943 Source: RC3 *

MCG +0-60-60 Hickson 98D PGC 72806 Multi-Galaxy Sys *
RA: 23h 54m 10.6s Dec: +00° 23' 38"
Mag: 17.5 S.B.: --- -V: --- Size: 0.3'x0.2' Class: S0+?
P.A.: 143 Inclination: --- R.V.: --- Source: RC3 *

PGC 72810 Hickson 98C Multi-Galaxy Sys *
RA: 23h 54m 13.8s Dec: +00° 21' 24"
Mag: 16.3 (B) S.B.: --- B-V: --- Size: 0.3'x0.2' Class: E?
P.A.: 163 Inclination: ---R.V.: +8145 Source: RC3 *

The central eg in this Hickson group (NGC 7783) is 2' S of a mag 10 *, SAO 128452. This is a curious looking thing with the two brightest eg forming an arc about 1.25' long and convex to the NE that contains two distinct centres. This is comprised by NGC 7783 and MCG +0-60-59. The brightest part of the arc is -83 that is 50" x 15" in PA 120, rises to the axis nr centre where there is a small, mod brighter elong core zone and a faint *ar nucleus.. It has a mag 15.5 * at the SE extremity where it joins -59
-59 is about 30" x 10" in PA 150 and in contact with the SE tip of -83 where there is a mag 15.5*, small elong halo with a slightly brighter core and a faint, intermittent *ar nucleus. To the south of this conjoined pair is a couple of very faint *s just on 1' distant that point N at -83 & -59.
The most distant of these two *s is seen as non-*ar at x260 having a very tiny, halo rising strongly to centre. This is PGC 72810.
-60-60 is at about the half-way point between the 10th mag * and NGC 7783. It is only visible occasionally and with considerable difficulty at x260 as a tiny non *ar spot of ephemeral gossamer. E/faint. The 10th mag * interferes considerably.

x195 25' TF x260 19' TF
IC 5357 Hickson 97A Multi-Galaxy Sys *
RA: 23h 47m 22.9s Dec: -02° 18' 03"
Mag: 14.0 (B) S.B.: --- B-V: --- Size: 1.4'x0.7' Class: SAB0- pec:
P.A.: 153 Inclination: ---R.V.: +6975 Source: RC3 *

IC 5351 Hickson 97D Multi-Galaxy Sys *
RA: 23h 47m 18.9s Dec: -02° 18' 51"
Mag: 14.6 (B) S.B.: --- B-V: --- Size: 0.7'x0.5'Class: E?
P.A.: 57 Inclination: --- R.V.: +6239 Source: RC3 *

IC 5356 Hickson 97C Multi-Galaxy Sys *
RA: 23h 47m 23.8s Dec: -02° 21' 04"
Mag: 15.0 (B) S.B.: --- B-V: --- Size: 0.8'x0.4' Class: S?
P.A.: 38 Inclination: --- R.V.: +5995 Source: RC3 *

IC 5359 Hickson 97B Multi-Galaxy Sys *
RA: 23h 47m 37.8s Dec: -02° 19' 00"
Mag: 15.7 (B) S.B.: --- B-V: --- Size: 1.2'x0.2' Class: S?
P.A.: 141 Inclination: --- R.V.: +6940 Source: RC3 *

This compact group is gathered around an 11th mag * GSC 5252:792. -57 is 2.5' NW, -51 is 3' W, -56 is SW by 2.5' and -59 is ENE by 1.5'.
-57 is probably the brightest of the group small, round or possibly off-round halo in PA 150, probably 50" x 40" of goodish S.B growing broadly and slightly to centre where there is a small slightly brighter zone.
-51 has a mag 13.5 * superimposed or perhaps just on edge to the S, because of that v/difficult to determine size, maybe almost 30" diameter, seems to grow weakly to centre.
-56 is probably 2nd brightest, small, round about 20-30" diameter across, growing broadly and slightly to centre. There are a couple of faint mag 15.5 *s < 1' S and E-W of each other. This maybe a pair though one (the E most one, in moments of better seeing looks non-*ar. Checked later on SkyMap and it certainly looks like a small very distant eg but no designation. A further search on NED revealed it to be a galaxy -- 2MASS J23472322-0221475 and to have a R/V (+5991) consistent with it being part of the physically bound group with the others. A magnitude supplied by NED was 17.18, but no info on what wavelength. It is almost certainly not a V magnitude.

-59 is of very LSB -- an edge on spindle eg, 40" x 5" in PA 135grows weakly to the axid near centre, no other structure. V/faint.

x195 25' TF x260 19' TF
NGC 7782 Galaxy *
RA: 23h 53m 54.0s Dec: +07° 58' 11"
Mag: 13.1 (B) S.B.: 13.2 B-V: +0.85 Size: 2.4'x1.2'
Class: SA(s)b P.A.: 175 Inclination: 4 R.V.: +5368 Source: RC3 *

NGC 7778 Multi-Galaxy Sys *
RA: 23h 53m 19.7s Dec: +07° 52' 15"
Mag: 13.7 (B) S.B.: 13.0 B-V: +0.96 Size: 1.0'x0.9' Class: E
P.A.: --- Inclination: --- R.V.: +5238 Source: RC3 *

NGC 7779 Multi-Galaxy Sys *
RA: 23h 53m 26.8s Dec: +07° 52' 32"
Mag: 13.7 (B) S.B.: 12.7 B-V: +0.99 Size: 1.4'x1.0' Class: (R')SA0/a:
P.A.: 10 Inclination: 3 R.V.: +5100 Source: RC3 *

NGC 7781 Galaxy *
RA: 23h 53m 46.0s Dec: +07° 51' 38"
Mag: 15.0 (B) S.B.: --- B-V: +1.09 Size: 0.7'x0.2' Class: S?
P.A.: 14 Inclination: --- R.V.: +5384 Source: RC3 *

All four here fit in a 19' x260 field comfortably. -82 is the largest and brightest and is a little apart from the others to the NE. -78, -79 & -81 are in a slightly curved line E-W about 7' long.

-78 and -79 are about 3' apart roughly E-W and similarly bright and similarly sized. Each on is about 40-50" diameter. -78 is marginally the smaller, both grow broadly and slightly to centre. -78 has a very faint *ar nucleus while -79 is a faint *aring -- not quite stellar.

-81 is about 5' ESE from them and has a mag 15.5 * on the W flank of the halo. Tiny fat spindle shaped halo in PA 0, 15" x 5"

-82 is a mod bright, oval elong eg about 1.5 to 1.75 x 1' in PA 0, very LSB outer halo, grows broadly and slightly to centre where there is a substantial, weakly brighter roundish core with a faint *arring at centre.

Best,

L.
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