Messier 84 (NGC 4374 / 3C 272.1)
J2000 coordinates, SBF distance (54.8 Mly), magnitude 9.10, western Markarian's Chain anchor, twin radio jets, and observing guide for Messier 84.
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.
| Parameter | Value | Uncertainty | Method & Epoch | Quality Status | Source Archive |
|---|---|---|---|---|---|
| Integrated visual magnitude (V) | 9.1 mag | ± 0.08 mag | Integrated CCD aperture photometry | definitive | Revised New General Catalogue and Index Catalogue (RNGC/IC) |
| Distance in light-years | 54800000 ly | ± 1700000 ly | HST ACS Virgo Cluster Survey surface-brightness fluctuations (16.8 ± 0.5 Mpc) | definitive | SH0ES Local Distance Ladder Hubble Constant |
| Apparent major axis | 6.5 arcmin | ± 0.3 arcmin | Optical isophotal dimensions (6.5′ × 5.6′) | definitive | Revised New General Catalogue and Index Catalogue (RNGC/IC) |
| Heliocentric recession velocity | 1017 km/s | ± 5 km/s | Optical stellar absorption spectroscopy | definitive | SIMBAD Astronomical Database (CDS) |
J2000 Equatorial Sky Chart & Culmination Altitude
The chart below plots Messier 84 (NGC 4374 Markarian Chain Core) at RA 12h 25m 03.71s, Dec +12° 53′ 13.1″ 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.
Astrophysical Context & Structure
Discovered by Charles Messier on March 18, 1781, during a single legendary observing session in which he logged eight Virgo Cluster galaxies plus the globular cluster M92, Messier 84 (NGC 4374) forms the bright western anchor of Markarian's Chain—a gracefully curving arc of eight bright galaxies spanning 1.5 degrees across the heart of the Virgo Cluster. Lying 54.8 million light-years away and just 17 arcminutes west of its twin giant Messier 86, M84 is a nearly spherical E1 elliptical (or face-on lenticular) galaxy spanning ~104,000 light-years.
In 1997 the Hubble Space Telescope Imaging Spectrograph (STIS) used M84 as one of its very first commissioning targets: by measuring a rapid 400 km/s Doppler rotation swing across a compact ionized gas and dust disk in the inner 80 light-years, STIS proved that M84 harbors a central supermassive black hole of ~1.5 billion solar masses.
That black hole powers the Fanaroff-Riley Class I radio source 3C 272.1, launching twin relativistic plasma jets that inflate enormous hour-glass-shaped cavities in M84's 10-million-kelvin X-ray halo—observed by the Chandra X-ray Observatory—while three Type Ia supernovae (SN 1957B, SN 1980I, and SN 1991bg, the prototype of sub-luminous Type Ia explosions) have erupted within M84's ancient stellar population.
Practical Visual Observing Guide
- Located midway between Denebola (β Leonis) and Vindemiatrix (ε Virginis), just 17′ west-southwest of M86 at the western end of Markarian's Chain.
- A wide-field eyepiece (40×–60×) in a 100–150 mm telescope easily captures M84, M86, and the interacting 'Eyes' galaxy pair (NGC 4435 and NGC 4438) in a single sweeping view.
- In a 200–250 mm telescope, M84 and M86 look like twin headlights surrounded by smaller NGC galaxies (including edge-on NGC 4388 and NGC 4402) forming the famous 'Face in Virgo' asterism.
Catalog Cross-Identifications & Aliases
Common Aliases: M84 · NGC 4374 · 3C 272.1 · UGC 7494
| Catalog Authority | Identifier |
|---|---|
| MESSIER | M 84 |
| NGC | NGC 4374 |
| SIMBAD | M 84 |
| WIKIDATA | Q14031 |
Related Objects, Comparisons & Guides
Messier 86 (NGC 4406 Blueshifted Lenticular)
J2000 coordinates, SBF distance (55.4 Mly), magnitude 8.90, −244 km/s blueshift, ram-pressure X-ray plume, and observing guide for Messier 86 in Virgo.
Messier 87 (Virgo A Giant Elliptical Galaxy)
Coordinates, distance (16.4 Mpc / 53.5 Mly), EHT 6.5-billion M☉ black hole M87*, relativistic jet, and observing guide for Messier 87.
Messier 88 (NGC 4501 Symmetrical Spiral)
J2000 coordinates, Tully-Fisher distance (54.1 Mly), magnitude 9.60, multi-arm SA(rs)b spiral, ICM compression edge, and observing guide for Messier 88.
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.
Apparent vs Absolute Magnitude Explained
Understand the logarithmic Pogson astronomical magnitude scale, apparent visual magnitude (m), absolute magnitude (M at 10 parsecs), and bolometric corrections.
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