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Entire DOCdb database of 18,816 objects.



NGC 7721 (17,961 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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altitude today

altitude (year)


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NGC 7721

NGC 7721, AGC 630233, LEDA 72001, MCG-01-60-017, II 432, h 2260, GC 4997

RA: 23h 38m 48.3s
Dec: −06° 31′ 5″

Con: Aquarius
Ch: MSA:1304, U2:304, SA:17


(reference key)

Type: galaxy, Sbc

Mag: B=12, V=?

Size: 3.09′ x 0.933′
PA: 15°

Historical observations

William Herschel (c.1784)

Synonyms: H II-432

Discovered in 1785 by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "pB, cL, E 75 degrees sp-nf, 3' long."

NGC/IC Dreyer (1888, 1895, 1908)

This 12.4 magnitude spiral galaxy is recorded in the NGC as "pretty faint, considerably large, elongated 12 , very gradually brighter in the middle."

Published comments

Helwan Obs. Bulletin No 15 (1915)

pF, s.5'x1', mE 20deg, spiral.

Knox Shaw, H. (1915)

Knox Shaw, H. (1915) Note on the nebulae and star clusters shown on the Franklin-Adams plates. M.N.R.A.S., 76(2), 105-107.

Comments on papers by Harding (MNRAS, 74(8)), and Melotte (MemRAS 60(5)) describing objects foundon the Franklin-Adams plates; compares with plates taken with the Reynolds reflector (Helwan Obs Bull. 9-15):

NGC 7721 is an elongated spiral. [previously included in Class II-Spindle-shaped Nebulae]

Sulentic & Tifft (1973)

(Sulentic and Tifft 1973) notes that this is a 12.5 mag galaxy. Their coded description reads S,EL,BM,SLDIF,BKNS DKPCHS NRCT,PD SSTR.

Photo index

by Jim Lucyk: Sky&Tel. 3/69 p148.

Modern observations

Tom Lorenzin

Lorenzin, in the e-version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "12.4M; 2.6' x 1' extent; soft oblong with little brighter center; alone in a starless void."

Steve Coe

Coe, using a 17.5" f/4.5, notes: "Faint, pretty large, elongated 2x1, with a somewhat brighter middle."

Brian Skiff

POSS: SB(s)cdIII in pa18.

15cm - barely vis.

- nice mod f gx @ 80x elong in pa20. 140x: halo occas stretches out as long

as sep to m12 * 5' SW. main body 2'.5x0'.8 w/wk even concen. no core or

nuc. fairly smooth texture, but a few occas *ings. BS, 14Oct1990,

Anderson Mesa.

25cm - fairly f, little concen to center. 2'x0'.75 in pa 30, lenticular outline,

core somewhat mottled at 180x. BS, Roof.

30cm - velong at lox, 3'x1' in pa30. little concen w/*ings in middle. hix: poor

uneven concen, mottly elong core.

Favourite lists

Lacaille's catalogue

The Messier objects

Dunlop's catalogue

The Bennett objects

The Caldwell list

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