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LEDA 23324 (5,246 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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Holmberg II

LEDA 23324, UGC 4305, Arp 268, Holmberg II, DDO 50, MCG+12-08-033, Holmberg II X-1, ZW VII 223

RA: 08h 19m 3.9s
Dec: +70° 43′ 9″

Con: Ursa Major
Ch: MSA:540, U2:22, SA:2


(reference key)

Type: galaxies (interacting), dI...

Mag: B=11.38, V=?

Size: 8.317′ x 6.165′
PA: 15°

Published comments

de Vaucouleurs, G. (1975)

de Vaucouleurs, G. (1975) Nearby groups of galaxies. In: Kuiper, G. (ed) Stars and Stellar Systems. Volume 9: Galaxies and the Universe. Chapter 14, p557.

5. The nearer groups within 10 megaparsecs

G2. M81 (NGC 3031 group)

Brightest members: 3031, 2403, 3034, 4236 & 2976.

This well known group centred on the M81-M82 pair in Ursa Major includes several late-type spirals and dwarf irregular satellites: NGC 2976, NGC 3077, IC 2574 (=DDO81), A0936 (HoI = DDO63) and A0814 (HoII = DDO50). Several large nearby spirals including NGC 2366, 2403 and possibly 4236 have comparably low velocities and may be outlying members of the grup. NGC 2403, NGC 2366 and A0814 and 2 or 3 other dwarfs (DDO 44, 51, 53) may in fact forma subgroup in a larger cloud extending into Camelopardalis and including also the low-latitude, obscured group formed by NGC 1560, NGC 1569, IC 342, IC 356, Maffei 1 and 2, and possibly several dwarfs (DDO 33, 38, 39). This cloud may be interrupted by the galactic absorption belt. … The M81 group includes two examples of the rare I0 (or Irr II) galaxy type, NGC 3034 and NGC 3077. Both display well-known optical and/or radio peculiarities.

Sandage and Tammann (1975)

Sandage and Tammann (1975, Astrophysical Journal, 196, 313-328) includes this galaxy in the M81 Group. Members include NGC 2366, NGC 2403, NGC 2976, NGC 3031, NGC 3034, NGC 3077, NGC 4236, IC 2574, UGC 5139 (Holmberg I) & UGC 4305 (Holmberg II),.

Holmberg II is also known as Arp 268.

Schmidt e al (1993)

Other names: "U4305, D50,HO II, ARP268,VII ZW223". Inclination: (face-on, in degrees) 35 Total photoelectric blue mag 11.10 Total colour index .44 Logarithm of the angular diameter D25 (arcminutes) 1.90 Blue photographic magnitude 10.9 This galaxy is included in a sample of galaxies with velocity less than 500km/s with respect to the centroid of the Local Group. [Nearby Galaxies. Schmidt K.-H., Priebe A., Boller T. (Astron. Nachr. 314, 371 (1993))]

Photo index

Photo index by Jim Lucyk: Sky & Tel. 3/85 p217, Rev.Shapley-Ames Cat.of Bright Gal. (Sandage,Tammann 1981) p113, Galaxies (Hodge,1986) p135

Modern observations

Tom Lorenzin

Tom Lorenzin, in the electronic version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "11M; 7'x 6' extent; no obs. data yet; see photo at HAG-39."

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