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NGC 7640 (17,792 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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NGC 7640

NGC 7640, LEDA 71220, MCG+07-48-002, UGC 12554, II 600, h 2236, GC 4950

RA: 23h 22m 6.52s
Dec: +40° 50′ 45.1″

Con: Andromeda
Ch: MSA:1120, U2:88, SA:9


(reference key)

Type: galaxy (in group), SBc

Mag: B=11.6, V=?

Size: 10′ x 1.949′
PA: 167°

Historical observations

William Herschel (c.1784)

Synonyms: H II-600

Discovered in 1786 by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "pB, mE np-sf but nearly in the meridian, lbM, resolvable, 5' long, 1.5' broad; also observed in 1784."

Published comments

Hardcastle, J.A. (1914)

Hardcastle, J.A. (1914) Nebulae seen on the Franklin-Adams plates. MNRAS, 74(8), 699-707. [commentary in Shapley, H. & Ames, A. (1932) A survey of the external galaxies brighter than the thirteenth magnitude.]

Classified as "Elongated."

Notes: "Lick Obs. Bull. 248, spiral."

Sulentic & Tifft (1973)

(Sulentic and Tifft 1973) notes that this is a 11.5 mag galaxy. Their coded description reads SB,MINC,BM,BDDIFARMS.

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

This galaxy appears on page 49 of "The Hubble Atlas of Galaxies" by Allan Sandage (1961, Washington, DC).

Photo index

by Jim Lucyk: Hubble Atl.of Gal. (Sandage 1961) p49.

Modern observations

Walter Scott Houston

Houston writes: "When the seeing and transparency are good, I can find the edge-on galaxy NGC 7640 from Connecticut with the 4-inch Clark. The view was easier from Kansas with the 10-inch. I make the magnitude of this difficult object to be about 10.9." In 1971 he called it a difficult galaxy: "a 12.5-inch once revealed it to me neatly as a narrow spindle, about as bright as a 12th mag star."

Sanford (1989) Observing the Constellations

lists this spiral galaxy in Andromeda as 10.9 magnitude and 10.7' x 2.5' in size.

Brian Skiff

Brian Skiff:

6cm - lg, diffuse, w/o concen. elong N-S, w/*s nrby.

15cm - barely vis @ 95x. BS.

25cm - fairly f. elong N-S, 7' long. enclosed in triangle of *s 5' on-a-side; gx

strung along W base. core mottled w/dk spots, 3'x1'. on E is m13.5 *. BS.

30cm - w/in triangle of m12.5 *s. pa170, 7'x2'. on sl concen to 1'.5 core, no

nuc. distracting m13.5 * on SE edge of core. inner halo mottled. CBL.

Tom Lorenzin

Lorenzin, in the e-version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "12.5M; 9' x 1' extent; very dim slash; nearly edge-on spiral; axis oriented N-S; little brighter center surrounded by right triangle of 12M stars with apex pointed E; fairly easy to see considering low magnitude; !good supernova prospect! <2 degrees SSW of planetary N7662; see photo at HAG-49."

Contemporary observations

Magda Streicher

(no date)

Alldays (22.50S, 20.12E, 770m).

12-inch f/10 SCT (95x, 218x)

Very elongated. Soft and just a whisper of light in a N-S direction. I will come back to this one. Oval, large core brighten slowly.

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