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NGC 1023 (1,881 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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NGC 1023

NGC 1023, LEDA 10123, MCG+06-06-073, UGC 2154, Arp 135, I 156, h 242, GC 575

RA: 02h 40m 23.9s
Dec: +39° 03′ 46.3″

Con: Perseus
Ch: MSA:100, U2:62, SA:4


(reference key)

Type: galaxies (interacting), SB0

Mag: B=10.5, V=?

Size: 7.943′ x 3.467′
PA: 87°


The brightest galaxy in Perseus. This galaxy has a peculiar lenticular shape and is more than 5' long. However, Admiral Smythe, using his 5.9" refractor, found it more oval in appearance. Often listed as mag 11, Sky Cat 2000 lists it a more realistic 9.5.

Historical observations

William Herschel (c.1784)

Synonyms: H I-156

Discovered in 1786 by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "cB, mE 12 degrees sp-nf, vBN, near 10' long."

Webb, T.W. (1893)

In the 5th edition of Webb's Celestial Objects for Common Telescopes it is described as "one of H's bright-class nebulae, lenticular, 5' long, with stellar nucleus."

Published comments

Doig, P. (1925)

Notes on the nebulae and clusters in Webb's 'Celestial Objects for Common Telescopes' (Sixth edition, Vol.ii). Part I. M.N.R.A.S., 35(5), 159.

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

G7. NGC 1023 Group.

Brightest members: 1023, 925, 891, IC 239, 1058, 1003

Several large spirals of type Sc and later including NGC 925, NGC 1003, NGC 1058 and IC 239 are clustered around the bright lenticular system NGC 1023 in low galactic latitudes at the border of Perseus and Andromeda. The edge-on Sb system NGC 891 and the close pair of late-type spirals NGC 672, IC 1727 are probable or possible outlying members. NGC 1156, a Magellanic irregular some 20° away, is another possible outlying member. ... The group is at the edge of the galactic absorption belt (which may conceal some members in lower latitudes) .. Several dwarf irregulars are probable members .. the overall dimensions of the group 20°x10° (including NGC 672) are rather large, but the diameter of the core around NGC 1023 is only 8°. ... two of the brightest supernovae appears in NGC 1003 and NGC 1058.

Photo index

Photo Index by Jim Lucyk: Sky&Tel. 1/84 p98, Sky&Tel. 12/81 p620, Astronomy mag. 1/84 p78, Deep Sky #16 Fa86 p28.

Arp (1966)

Listed as No. 135 in Arp's "Atlas of Peculiar Galaxies" (Astrophysical Journal Supplement, vol. 14, 1966.) He remarks "similar nebulosity about one diameter further east."

Sandage & Tammann (1975)

Sandage, A. & Tammann, G. A. (1975) Steps toward the Hubble constant. V - The Hubble constant from nearby galaxies and the regularity of the local velocity field. ApJ, 196, 313-328. [1975ApJ...196..313S]

Sandage and Tammann (1975, Astrophysical Journal, 196, 313-328) includes this galaxy in the NGC 1023 Group. Members include NGC 891, NGC 925, NGC 1003, NGC 1023, NGC 1058 & IC 239.

Sandage, A. (1961) The Hubble Atlas of Galaxies

This galaxy appears on page 40 of "The Hubble Atlas of Galaxies" by Allan Sandage (1961, Washington, DC).

Sulentic & Tifft (1973)

The RNGC (Sulentic and Tifft 1973) notes that this is a 11.0 mag galaxy. Their coded description reads EL,BM,DIFHALO,COM)) BDIF PCH F END.

Modern observations

Steve Gottlieb

02 40.4 +39 04

17.5: bright, large, very elongated 7:2 ~E-W, very bright core, almost stellar nucleus. Large fainter halo increases size to 7'x2'. Two 15th magnitude stars are superimposed on the W and E ends.

13: very bright, impressive, elongated ~E-W, bright core, stellar nucleus.

8: fairly bright, bulging bright core, lens-shape.

Walter Scott Houston

Houston notes that this galaxy, just inside the western border of Perseus, is about 5' by 2' in extent. He estimates the magnitude as 10.1 with a 4-inch refractor.

Gross, Todd (IAAC)

Your skill: Intermediate ; Date and UT of observation: 08/31/97 0755 GMT; Location & latitude: 22 miles west of Boston, Ma. 42.3N; Site classification: Suburban; Limiting magnitude (visual): 5.1 (estimated) 5.1(est) in vicinity of object; Seeing (1 to 10 - worst-best): 6; Moon up (phase?): Yes, crescent; Instrument: 16" Dob, 96%, 99% coatings, Televue binoviewer; Magnifications: 232; Filters used: none; Object: NGC 1023

Bright and easy in suburban skies due to it's small length of under 4 arc minutes. Very elongated with two stars of approximately 13th magnitude superimposed on either (long) side. Bright, almost bar-like core, with a nearly stellar nucleus.

Tom Lorenzin

Tom Lorenzin, in the electronic version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "11M; 4.5'x 1.3' extent; lenticular galaxy with much brighter center; look for faintly brighter patch on E tip; good supernova prospect."

Ancient City Astron.Club (1980)

Listed by the Herschel Club, described as "definite elongation seen, bright, starlike nucleus, fainter, thin outer arms, situated in a nice star field. 6-inch, 48x."

Contemporary observations

Tom Bryant

2009 12 23 21:16:32

Observing site: Little Tycho Observatory

Telescope: C-8

[2h 40m 24s, 39 4m 0s] A bright galaxy, with a bright compact nuclueus. Seen despite a quarter moon and light pollution. A face on Sa?

Favourite lists

Lacaille's catalogue

The Messier objects

Dunlop's catalogue

The Bennett objects

The Caldwell list

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