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NGC 4254 (9,051 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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Coma Pinwheel

NGC 4254, LEDA 39578, MCG+03-31-099, MRC 1216+146, UGC 7345, Katherine's Wheel, Virgo Cluster Pinwheel, Messier 99, Coma Pinwheel, h 1173, GC 2838

RA: 12h 18m 49.52s
Dec: +14° 25′ 0.4″

Con: Coma Berenices
Ch: MSA:726, U2:193, SA:13


(reference key)

Type: galaxy (HII), Sc

Mag: B=10.2, V=?

Size: 5.37′ x 4.677′
PA: ?


NGC 4254 is also known as the Pinwheel Galaxy. Note that NGC 598 & NGC 5457 are also known as the Pinwheel.

Historical observations

William Herschel (1787)

In the Appendix to the 1912 'Scientific Papers of Sir William Herschel' this object is described as "1787, January 14. vB, vL, vgmbM, and the brightness taking up a great space."

Lassell, W. (1866)

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

Sketched and described.

Published comments

Sanford (1989) Observing the Constellations

Sanford calls it "a wide-open face-on spiral with two prominent arms which become evident in a 16-inch."


Two supernovae erupted in this galaxy; 1967 (14.0p), 1972 (15.0b)

Sulentic & Tifft (1973)

(Sulentic and Tifft 1973) notes that this is a 10.5 mag galaxy. Their coded description reads SC,BKNDIFWD ARMS MORE DIF STR F NUC.

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 29 of "The Hubble Atlas of Galaxies" by Allan Sandage (1961, Washington, DC).

Doig, P. (1925)

Doig, P. (1925) Notes on the nebulae and clusters in Webb's 'Celestial Objects for Common Telescopes' (Sixth edition, Vol.ii). Part V. M.N.R.A.S., 36(3), 89.

Bailey, S.I. (1908)

"nebula, nucleus; spiral?"

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

Modern observations

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

Hartung notes that this "appears as a round fairly bright luminous haze about 2.5' across, rising steadily to a broad centre with no visible nucleus . . 7.5cm will pick up this object."

Tom Lorenzin

Lorenzin, in the electronic version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "10M; 5' diameter; bright, large and round with barely brighter center; some mottling visible with persistent scrutiny; bright, non-stellar core; see photo at HAG-29; shares the name "Pinwheel Galaxy" with M-33 and M-101; !good supernova prospect!."

Brian Skiff

= M99

33cm plate: m12.5 * 1'.9 ESE.

6cm - pretty easy w/averted vis, but not only using it. broad 3'x2' smudge elong E-W w/some concen.

7cm - fairly br circ glow of modsfcbr. smooth texture, mod broad concen to sm, wkly brtr core. occas sl *ing or disturbance on SE edge. BS, 15Apr1993, Anderson Mesa.

15cm - 4' diam but fairly f. light grows gradually brtr to a vbroad diffuse core. looks gran.

- big br patch SW of m6.5 *. vsl elong NE-SW. BS, 7Feb1984, USNO.

25cm - vbr w/lg core sim to unres gc. arm extends N. 3' diam overall.

- 180x: 4' diam. brtr center, core 1' across. many f *s in fld, incl consp one on E edge of core. core in dicative of spir struc.

30cm - 3'x2'.8 in pa100; mod concen, which shows best at hix. core definitely uneven, 50" across. broad core overall, w/much vf halo. f *s assoc and around. m13 * 1'.8 SE.

- m12.5 * on ESE just off edge of core. spir arm clearly vis wrapping around core on S&E; it has br patches in it immed SE of core, on S edge of halo (this one elong), and 1'.5 W of center, whereupon it peters out. *s on N side delimit border there. poss second arm vshort sticks out a little nr these *s from NW side. core oval in pa60. even concen to sub*ar nuc. sketch in notes. BS, 7Feb1984, USNO.

Contemporary observations

Tom Bryant

2007-03-18 10:30:00

Observing site: Pinnacles overlook

Telescope: C-8

[12h 18m 48s, 14 25m 0s] An elliptical patch in the sky. The nucleus is indistinct, and the patch is mottled.

2011 6 29 23:0:34

Observing site: Little Bennett Regional Park

Telescope: C-11

[12h 18m 48s, 14 25m 0s] A large, bright hazy disk with a diffuse nucleus.

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's diffuse and faint spiral arms is clearly seen edge on and is well define with a bright nucleus seen at both 57*and 75*.This galaxy however has an elongated structure in my scope.This galaxy measures 7.1'* 1.7'with PA NNW/SSE. The central nucleus is brighter compared to the spiral arms of this galaxy.

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