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NGC 520 (1,019 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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NGC 520

NGC 520, VV 231, Arp 157, LEDA 5193, MCG+01-04-052, UGC 966, III 253, h 116, GC 303

RA: 01h 24m 35.42s
Dec: +03° 47′ 24.8″

Con: Pisces
Ch: MSA:242, U2:218, SA:10


(reference key)

Type: galaxies (interacting), I

Mag: B=12.4, V=?

Size: 4.897′ x 2.137′
PA: ?

History and Accurate Positions for the NGC/IC Objects (Corwin 2004)

NGC 520 is apparently an interacting galaxy. Classified as an I0 by de Vaucouleurs, the distorted dust lane and unresolved bulge with plumes may be the result of a collision. Vorontsov-Velyaminov marks three components in his Atlas of Interacting Galaxies; I've provided positions for them in the table.

However, in the near-infrared, the structure is simpler with a bright peak at the center connected by a bridge to a somewhat fainter knot to the northwest (this fainter knot has no optical counterpart). The central peak breaks up into at least three hot spots in the 2MASS J-band. The J2000.0 positions are

Central peak, K-band: 01 24 34.89 +03 47 30.1 Central peak, H-band: 01 24 34.86 +03 47 29.9 Central peak, J-band: 01 24 34.86 +03 47 28.3 southeast spot Central peak, J-band: 01 24 34.65 +03 47 35.0 northwest spot Central peak, J-band: 01 24 35.04 +03 47 33.1 northeast spot Northwestern knot: 01 24 33.33 +03 48 02.8

The southern of the three optical components (VV 231b) corresponds most closely to the position of the infrared/radio nucleus.

Historical observations

William Herschel (c.1784)

Synonyms: H III-253

Discovered in 1784 by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "eF, cL, E."

Birr Castle/Lord Rosse

(72-inch f/8.8 speculum telescope) "Dec 18, 1851. South end of nebula is like a brush or broom with a split."

Published comments

Arp (1966)

Listed as No. 157 in Arp's "Atlas of Peculiar Galaxies" (Astrophysical Journal Supplement, vol. 14, 1966.) He remarks "note segment in northeast direction."

Sulentic & Tifft (1973)

(Sulentic and Tifft 1973) notes that this is a 12.5 mag galaxy. Their coded description reads VCOMPLEXIRR,SEVDKLNS SEV DIFFILS,SEVBCOMPONENTS.

Sandage, A. et al. (1975) Galaxies and the Universe

G. de Vaucouleurs ("Galaxies and the Universe", Chapter 14 - Nearby Groups of Galaxies) notes that the five brightest members of the NGC 488 Group are NGC 488, NGC 474, NGC 520, NGC 521 & NGC 470.

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

This galaxy appears on page 41 of "The Hubble Atlas of Galaxies" by Allan Sandage (1961, Washington, DC).

Hodge, P.W. (1972)

Hodge, P.W. (1972) Some current studies of galaxies. Sky&Telescope, July, 23.

Photo index

by Jim Lucyk: The Astrograph 6-7/88 p88, Burnhams V3 p1482, Hubble Atl.of Gal. (Sandage 1961) p41, Galaxies (Hodge,1986) p145.

Modern observations

Tom Lorenzin

Lorenzin, in the electronic version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "12M; 4'x 2' extent; photo at HAG-41."

[amastro] Bill Ferris

Date: 10/04/1999 Loc.: Anderson Mesa, Flagstaff AZ Weather: Clear, calm, temps in mid 30's Scope: 10-inch, f/4.5 equatorial mount Newtonian Eyepiece (Mag.): 18 mm SWA w/ 3x TeleVue Barlow (190x) 8.8 mm UWA (129x)

NGC 520 is an odd fish. It's located about two degrees ENE of the aforementioned galaxy trio. A triangle of 11th magnitude stars stand sentry a quarter degree to the Northeast. NGC 520 is an 11.4 magnitude object, classified as a peculiar galaxy in the RC3. At 129x, it appeared 60" x 20" in size with what appeared to be two stars in the foreground, one at each end. A check of the DSS online POSS image leads me to believe this is actually a pair of interacting galaxies. So now, I'm wondering if I saw the cores of the interacting pair?

Steve Coe

Coe, using a 13.1" f/5.6, notes: ""NGC 520 Pretty bright, pretty large, elongated 2 X 1 in PA 135 and much brighter in the middle at 165X. The strange characteristic of this galaxy is that it has an elongated core. The central bright section of this object is a streak instead of the usual round spot."

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