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NGC 4321 (9,251 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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Messier 100

NGC 4321, LEDA 40153, MCG+03-32-015, UGC 7450, Messier 100, h 1211, GC 2890

RA: 12h 22m 54.95s
Dec: +15° 49′ 19.5″

Con: Coma Berenices
Ch: MSA:701, U2:193, SA:13


(reference key)

Type: galaxy (AGN), Sc

Mag: B=10.6, V=?

Size: 7.585′ x 6.165′
PA: 30°

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

NGC 4321. See NGC 4322, NGC 4323, and NGC 4327.

Historical observations

William Herschel (c.1784)

In the Philosophical Transactions, 1814, William Herschel described it as "a nebula of about 10' in diameter, but there is in the middle of it, a small, bright cluster of supposed stars."

Lassell, W. (1866)

Bibcode: [1866MmRAS..36....1L]

Sketched and described.

Published comments


Four supernovae erupted in this galaxy; 1901 (12.1p), 1914 (14.0p), 1959 (17.5p), 1979 (11.0v)

Sulentic & Tifft (1973)

(Sulentic and Tifft 1973) notes that this is a 10.5 mag galaxy. Their coded description reads SC,B,SC,2BWDKNY ARMS.

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 Virgo I (S) group are NGC 4321, NGC 4501, NGC 4254, NGC 4569 & NGC 4579.

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

This galaxy appears on page 28 of "The Hubble Atlas of Galaxies" by Allan Sandage (1961, Washington, DC).

Bailey, S.I. (1908)

"nebula, B nucleus, spiral?"

Bailey, S.I. (1908) A catalogue of bright stars and nebulae. Ann.Harv.Coll.Obs., 60(8), 199.

Remarks, p.217: "the spiral structure of this nebula is not well shown on A1875 having an exposure of 62 minutes."

Modern observations

Hartung, E.J. (1968) Astron.Obj.South.Tel

Notes that this "is a large diffuse luminous haze about 4' across, rising broadly and then suddenly to a small bright nucleus with no visible structure." He notes that from his location, M100 culminates at 35 deg, and adds: "I see them very easily with 10.5cm."

Walter Scott Houston

In 1972 Houston wrote: "Looking at a galaxy, one sometimes gets the feeling that a little more aperture would show the stars. Such a case is the 10th mag broadside system M100, which is about 5' in diameter." Working with his 6-inch refractor and noting that this object brightened from attenuated edges towards the centre, Smyth declared that M100 'is therefore proved to be globular.' But with Lord Rosse's 6-foot mirror no stars were seen, and M100 was characterized with one word: 'Spiral'."

Sanford (1989) Observing the Constellations

Notes that it "has been called the brightest galaxy in the Virgo Cluster. It appears as a large haze 6.9' x 6.2' across. In 4-inch or larger aperture telescopes, two major arms are seen wrapped around the nucleus. M 100 has produced several supernovae, with such events taking place in 1901, 1914, 1959 and 1984. A typical supernova at this distance reaches about 12th magnitude, easily seen in 8-inch or larger aperture telescopes."

Tom Lorenzin

Lorenzin, in the electronic version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "10M; 7' x 6' extent; soft, round, mottled glow with distinct central condensation; two 14M stars 1' each to SW and ESE; see photos at HAG-28-31; faint SP GAL N4312 (12.5M; 2.6' x 1.6' extent) is a very gentle spindle 17' to SSW just past 10M star."

Brian Skiff

= M100

UGC: pa30.

33cm plate: * 2'.7 SE. br patch NW is sector of spir arm.

UBV for fld *s in PASP 93,36.

T&B: * NW V=13.0.

6cm - nice, smoothlu textured w/little concen except for a f non*ar nuc. elong in pa110, 4'x3' overall.

7cm - br, mod lg @ 30x. 50x: sl oval, elong ~E-W, halo reaches 2/3 distance to m13 * off NW side. mod broad concen to sm brtr core w/o sharp nuc. BS, 15Apr1993, Anderson Mesa.

13cm - vbr oval elong ESE-WNW. uniformly br halo and vsm much brtr core. BS, 7Feb1984, USNO.

15cm - 5' diam, broad, rising gradually to a sm brtr core. at times the neb is gran. some f *s on E side.

25cm - 5'x4', elong SE-NW. br core. muich of area seems curdled and mottled. sev *s noted in neb.

30cm - 149x: pretty f, elong pa120, 3'x1'. 238x: 4'.5x3' in pa120. not well concen but w/sm br 20" core. core is contrarily oriented in pa60, with little wings on NE & SW. sev *s assoc just in edge of extensive uneven halo. sketch in notes.

- 5'x4' in pa115. m13 * on SE edge. core seems vsl oval in pa80, no nuc evident. consp br patch nr uoter edge of halo NW of center. a few other br & dk spots/*ings and a couple of *s over gx. BS, 7Feb1984, USNO.

Contemporary observations

Magda Streicher

(no date)

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

12-inch f/10 SCT (218x)

This is a pretty large Coma galaxy member, which show off as a large glow. HP show hints of wheel structure which I suspect with averted vision. 16" show two sweeping irregularities extending from core. Sharp small star like nucleus, very hazy on the edges. Will go back and made a sketch.

Tom Bryant

2007-03-18 10:30:00

Observing site: Pinnacles overlook

Telescope: C-8

[12h 22m 54s, 15 49m 0s] An almost face on Sc. It has a bright nucleus, and a fainter, uniform disk, with the 24.5mm Ultrawide.

Richard Ford

2012 March 23rd, Fri



Sky Conditions:The fainter parts of the Milky Way are barely visible.Haziness only visible on the horizon.Atmosphere stable with little interference.

Instrument:12-inch Dobsonian.

This galaxy has a circular shape with prominent spiral arms which are clearly observed with a brilliant oval nucleus strongly condensed.This galaxy measures 8.2'* 2.7'.The central nucleus of this galaxy grows brighter compared to the far outskirts of this galaxy.

Favourite lists

Lacaille's catalogue

The Messier objects

Dunlop's catalogue

The Bennett objects

The Caldwell list

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