Galaxies · Constellation Virgo

Messier 60 (NGC 4649 / Arp 116)

J2000 coordinates, SBF distance (54.8 Mly), magnitude 8.80, 4.5-billion-M☉ black hole, NGC 4647 companion, and observing guide for Messier 60.

Right Ascension (J2000.0)12h 43m 40.01s
Declination (J2000.0)+11° 33′ 09.4″
Primary ClassificationGiant E2 elliptical galaxy paired with spiral NGC 4647 (Arp 116)
Best Observing SeasonSpring (March–June)

Provenance-Backed Scientific Measurements

Every measurement below preserves its unit, uncertainty interval, observational method, reference epoch, quality status, and primary catalog source. See Uncertainty & Provenance for how competing measurements are handled.

Astrometric, Photometric, and Physical Parameters for Messier 60 (NGC 4649 / Arp 116)
ParameterValueUncertaintyMethod & EpochQuality StatusSource Archive
Integrated visual magnitude (V)8.8 mag± 0.08 magIntegrated CCD aperture photometrydefinitiveRevised New General Catalogue and Index Catalogue (RNGC/IC)
Distance in light-years54800000 ly± 1800000 lyHST ACS Virgo Cluster Survey surface-brightness fluctuations (16.8 ± 0.55 Mpc)definitiveSH0ES Local Distance Ladder Hubble Constant
Apparent major axis7.4 arcmin± 0.4 arcminOptical isophotal dimensions (7.4′ × 6.0′)definitiveRevised New General Catalogue and Index Catalogue (RNGC/IC)
Heliocentric recession velocity1110 km/s± 5 km/sOptical stellar velocity-dispersion spectroscopydefinitiveSIMBAD Astronomical Database (CDS)
Measurement Uncertainties & Competing Solutions: HST SBF distance determinations place M60 at 16.8 ± 0.55 Mpc (54.8 ± 1.8 Mly), while Cepheid and SN Ia measurements of overlapping spiral companion NGC 4647 indicate the two galaxies lie within ~1 Mpc of each other and are beginning weak tidal interaction.

J2000 Equatorial Sky Chart & Culmination Altitude

The chart below plots Messier 60 (NGC 4649 Giant Elliptical Pair) at RA 12h 43m 40.01s, Dec +11° 33′ 09.4″ within Virgo, alongside peak meridian transit altitudes for 40°N and 30°S observers. Use the RA/Dec Coordinate Converter to compute exact culmination altitude for your latitude.

J2000 Equatorial Sky Position (Virgo) +90° 0° −90° 24h 12h RA 0h Peak Meridian Altitude 62° 40°N Lat 48° 30°S Lat RA: 12h 43m 40.01s Dec: +11° 33′ 09.4″ Epoch: J2000.0 · V = 8.8 mag First-party vector diagram derived from IAU / CDS SIMBAD / Gaia DR3 astrometry.

Astrophysical Context & Structure

Discovered by Johann Gottfried Koehler on April 11, 1779, Messier 60 (NGC 4649) is the third-brightest giant elliptical galaxy in the Virgo Cluster (after M49 and M87), dominating the cluster's eastern sub-group from a distance of 54.8 million light-years. Spanning roughly 120,000 light-years across and weighing ~1 trillion solar masses, M60 is surrounded by a dense swarm of ~5,100 globular clusters and an extensive halo of 10-million-kelvin X-ray-emitting plasma.

Stellar-dynamical orbit modeling with the Hubble Space Telescope and Keck adaptive optics reveals that M60's central velocity dispersion (~385 km/s) is driven by one of the most massive black holes in the local universe: a 4.5 ± 1.0 billion-solar-mass colossus nearly rivaling M87*. Even more remarkably, M60's satellite ultra-compact dwarf galaxy M60-UCD1 packs 200 million solar masses into a radius of just 80 light-years and harbors its own 21-million-solar-mass black hole—the stripped nuclear remnant of a once-massive galaxy.

On the sky, M60's golden-yellow elliptical halo overlaps just 2.5 arcminutes southeast of the blue, dusty spiral galaxy NGC 4647 (magnitude 11.3), forming the famous contrasting pair cataloged by Halton Arp as Arp 116.

Practical Visual Observing Guide

Minimum Instrument70–80 mm telescope (150 mm+ to resolve NGC 4647 companion)
Recommended Magnification60×–150×
Best Evening SeasonSpring (March–June)
  • The easternmost Messier galaxy in Virgo, situated 3.2° west-northwest of Vindemiatrix (ε Virginis)—the easiest entry point for star-hopping westward into the Virgo Cluster.
  • At magnitude 8.8, M60 is readily visible in 70–80 mm telescopes and shares a low-power field with M59 (25′ WNW).
  • In a 150–250 mm telescope at 120×–180×, look just 2.5′ northwest of M60's bright core to spot the ghostly 11.3-mag round patch of companion spiral NGC 4647 brushing against M60's halo.

Catalog Cross-Identifications & Aliases

Common Aliases: M60 · NGC 4649 · UGC 7898 · Arp 116

Cross-Catalog Identifiers for Messier 60 (NGC 4649 / Arp 116)
Catalog AuthorityIdentifier
MESSIERM 60
NGCNGC 4649
SIMBADM 60
WIKIDATAQ13978
Related Object · Virgo

Messier 59 (NGC 4621 E5 Elliptical Galaxy)

J2000 coordinates, SBF distance (50.2 Mly), magnitude 9.60, counter-rotating core, inner stellar disk, and observing guide for Messier 59 in Virgo.

Reference Guide

Angular Size, Separation & Field of View

How angular diameter (degrees, arcminutes, arcseconds), spherical angular separation, and small-angle physical diameter relate to telescope field of view.

Scientific Sources & Dataset Provenance

  • Revised New General Catalogue and Index Catalogue (RNGC/IC) (2024/2026 edition): Steinicke, W. 2010, Observing and Cataloguing Nebulae and Star Clusters (Cambridge Univ. Press); Verga, M. OpenNGC (CC-BY-SA 4.0 / data tables) — Wolfgang Steinicke / OpenNGC
  • SH0ES Local Distance Ladder Hubble Constant (2022 Baseline Cepheid + SN Ia): Riess, A. G., et al. 2022, ApJL, 934, L7 (A Comprehensive Measurement of the Local Value of the Hubble Constant) — SH0ES Collaboration (HST / JWST)
  • SIMBAD Astronomical Database (CDS) (2026-10 release): Wenger, M., et al. 2000, A&AS, 143, 9 (The SIMBAD astronomical database) — Centre de Données astronomiques de Strasbourg