NGC 70 group (NGC 70 = UGC 174, IC 1539, Arp 113) Galaxies in Andromeda

NGC 70 is located at: RA 00 hours 18 minutes 37 seconds, Dec +30 degrees 04 minutes 46 seconds

NGC 70 = Size: 1.9' x 1.2' Magnitude: 14.2 photographic Class: Sa(r)bc (SA(rs)c)*

North is up

West to the right

Telescope:

 14.5" f5 Newtonian reflector

Camera:

  ST-8XME, self-guided, binned 1x1, temp - 10c & -15c, camera control MaxIm DL 4.56

Image:

Lumicon Red filter, 1010 minutes (101 x 10 minute subs), 10/19/20/22/25/26/2017; seeing 2.8-6.2 FWHM per CCDStack

Processing: CCDStack 2.94.6355.18107, Photoshop CS5.1
Location:

 Rolling Roof Observatory, Thousand Oaks, CA 91360 (+34d 13m 29s -118h 52m 20s)

Notes:* This group of galaxies in Andromeda was a challenge to image ... in, and around, the off-shore (Santa Ana) winds, with poor to terrible seeing.

See this marked image (NGC's only).

From the NGC / IC Project:

NGC 68 = Arp 113 = VV 166b = Holm 6a = UGC 170 = MCG +05-01-065 = CGCG 499-106 = WBL 007-008 = PGC 1187

00 18 18.5 +30 04 18

V = 12.9;  Size 1.2'x1.1'

 

24" (9/15/12): at 322x appeared fairly faint to moderately bright, fairly small, round, 25" diameter, high surface brightness though contains a brighter nucleus.  One of the brighter members in a dense group of galaxies and forms a tight trio with NGC 70 1.0' NE and NGC 71 1.3' SE.  In addition, CGCG 499-104 is just 57" SW.  In total, 10 galaxies were logged in a 5' circle!

 

18" (11/14/09): fairly faint, small, round, 25" diameter.  Appears as a compact knot (like a core) of moderate surface brightness with no outer halo.  Forms the southwest vertex of a tight trio with NGC 70 and NGC 71 in a dense group.

 

17.5" (8/27/87): faint, small, slightly elongated WNW-ESE, weak concentration.  This galaxy is the brightest in a compact group and first in an interconnected trio with NGC 70 1.0' NE and NGC 71 1.2' SE.  An extremely difficult galaxy, NGC 67, is just 0.9' SW.

 

WH discovered NGC 68 = H V-16 = h15 on 11 Sep 1784 (sweep 266) and recorded "eF, 5 or 6' dia, 3 or 4 stars in it; but they seem to have connection with it."  This is the only galaxy Herschel discovered in the group, but he listed it in his fifth class of "large" nebulae, and Corwin comments it's likely he saw the merged light of NGC's 68, 70, and 71 (3 brightest in a small triangle in the core).  R.J. Mitchell, using LdR's 72" on 7 Oct 1885, made a sketch of NGC 67, 68, 69, 70, 71, 72, 74, and it was included in the 1861 Rosse publication.  The NGC position matches UGC 170 = PGC 1187.

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NGC 69 = Arp 113 = VV 166e = Holm 6f = MCG +05-01-066 = CGCG 499-105 = WBL 007-007 = PGC 1191

00 18 20.5 +30 02 24

V = 14.8;  Size 0.5'x0.3'

 

24" (9/15/12): faint, very small, round, 15" diameter, bright quasi-stellar nucleus.  Member of the compact NGC 68 group and first in a string with NGC 72 1.8' E and NGC 72A 3.0' E.

 

18" (11/14/09): very faint, extremely small, round, 15" diameter.  Located 1.6' SSE of NGC 71 and a similar separation due west of NGC 72.

 

17.5" (8/27/87): extremely faint and small, faint stellar nucleus.  In the core of the NGC 68 group with NGC 67 1.8' NW, NGC 71 1.6' NNE, NGC 72 1.8' E.

 

R.J. Mitchell discovered NGC 69 on 7 Oct 1855 using LdR's 72", while observing the NGC 68 group.  It's clearly shown on the sketch on plate XXV in the 1861 publication. The NGC position matches CGCG 499-105 = PGC 1191.

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NGC 70 = Arp 113 = VV 166a =  Holm 6c = UGC 174 = MCG +05-01-067 = CGCG 499-108 = WBL 007-010 = IC 1539 = PGC 1194

00 18 22.6 +30 04 47

V = 13.5;  Size 1.4'x1.2';  Surf Br = 13.9;  PA = 0d

 

24" (9/15/12): fairly faint to moderately bright, fairly small, slightly elongated ~N-S.  Extends between two mag 14 stars separated by 42".  Sharply concentrated with a small, high surface brightness core and a much fainter halo.

 

18" (11/14/09): fairly faint, fairly small, elongated 3:2 N-S, sandwiched between two mag 13.5-14 stars at the NNE and SW ends [42" separation].  Sharply concentrated with a very small bright core and a diffuse, low surface brightness halo that might extend to 0.8'x0.6', though the stars confuse the extent of the halo.  Forms the northern member of a very tight trio with NGC 71 1' SSE and NGC 68 1' SW.  A total of 9 members were viewed within a 7' circle!

 

17.5" (8/27/87): very faint, very small, round, small bright core.  Located in the core of NGC 68 group and nearly between two mag 13.5 stars 25" NE and 20" SSW.  In an interconnected trio with NGC 68 1.0' SW and NGC 71 1.0' SSE.

 

R.J. Mitchell discovered NGC 70 on 7 Oct 1855 while observing the NGC 68 group.  It was accurately placed on the sketch (plate XXV, fig 1) in the 1861 publication.  The NGC position matches UGC 174 = PGC 1194.  Bigourdan found the galaxy again on 19 Dec 1897, while misidentifying a star as NGC 70, and it was catalogued as IC 1539.  So, NGC 70 = IC 1539.  See Corwin's notes

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NGC 71 = Arp 113 = VV 166c = Holm 6b = UGC 173 = MCG +05-01-068 = CGCG 499-107 = WBL 007-009 = PGC 1197

00 18 23.5 +30 03 48

V = 13.2;  Size 1.2'x1.1';  Surf Br = 13.4

 

24" (9/15/12): fairly faint to moderately bright, fairly small, round, sharply concentrated with a high surface brightness 0.4' core and a much fainter halo to 40" diameter.  In a tight group of 10 galaxies including NGC 67, 68, 69, 70, 71, 72, 74, along with numerous stars mixed in!  A mag 14 star is 40" ENE.

 

18" (11/14/09): fairly faint, small, round, 25" diameter.  Compact appearance with a fairly high uniform surface brightness.  A mag 13.5 star is close following [38" ENE].  Forms the SE vertex of a tight equilateral triangle of galaxies with NGC 68 and NGC 70.

 

17.5" (8/27/87): very faint, small, oval ~E-W, weak concentration.  Member of the NGC 68 group and third in a close trio with NGC 68 1.2' NW and NGC 70 1.0' NNW.

 

R.J. Mitchell discovered NGC 71 on 7 Oct 1855 while observing the NGC 68 group.  It was accurately placed on the sketch (plate XXV, fig 1) in the 1861 publication.  Heinrich d'Arrest independently found the galaxy on 23 Sep 1865.

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NGC 72 = Arp 113 = VV 166d = Holm 6d = UGC 176 = MCG +05-01-069 = CGCG 499-109 = WBL 007-011 = PGC 1204

00 18 28.3 +30 02 26

V = 13.5;  Size 1.1'x0.9';  Surf Br = 13.3;  PA = 15d

 

24" (9/15/12): fairly faint, small, slightly elongated, 30"x24", very small brighter nucleus.  Member of the compact NGC 68 group and in a string with NGC 60 1.7' W and NGC 72A 1.3' ESE.

 

18" (11/14/09): faint, small, slightly elongated, 35"x30" diameter, low even surface brightness.  Located 2-3' SE of a tight trio (NGC 68/70/71).  NGC 72A, an extremely compact galaxy, lies 1.3' E.

 

17.5" (8/27/87): very faint, very small, elongated ~E-W, weak concentration.  Located in the core of the NGC 68 group with NGC 72A 1.3' ESE, NGC 69 1.8' W, NGC 71 1.7' NW.

 

R.J. Mitchell discovered NGC 72 on 7 Oct 1855 while observing the NGC 68 group.  It was accurately placed on the sketch (plate XXV, fig 1) in the 1861 publication.  The NGC position matches UGC 176 = PGC 1204.

 

* NED classification