Galaxies · Constellation Cetus

Cetus A (Messier 77 / NGC 1068)

J2000 coordinates, distance (47.0 Mly), magnitude 8.87, obscured active galactic nucleus, IceCube neutrino emission, and observing guide for Messier 77.

Right Ascension (J2000.0)02h 42m 40.71s
Declination (J2000.0)-00° 00′ 47.8″
Primary ClassificationPrototype Type 2 Seyfert active galaxy & cosmic neutrino source
Best Observing SeasonAutumn to Early Winter (October–January)

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 Cetus A (Messier 77 / NGC 1068)
ParameterValueUncertaintyMethod & EpochQuality StatusSource Archive
Integrated visual magnitude (V)8.87 mag± 0.08 magIntegrated CCD aperture photometrydefinitiveRevised New General Catalogue and Index Catalogue (RNGC/IC)
Distance in light-years47000000 ly± 3900000 lyVLBA H2O megamaser geometric disk kinematics & Tully-Fisher relation (14.4 ± 1.2 Mpc)high-confidenceSIMBAD Astronomical Database (CDS)
Apparent major axis7.1 arcmin± 0.3 arcminOptical isophotal dimensions (7.1′ × 6.0′)definitiveRevised New General Catalogue and Index Catalogue (RNGC/IC)
Heliocentric recession velocity1137 km/s± 3 km/sH I 21-cm and optical emission-line spectroscopydefinitiveSIMBAD Astronomical Database (CDS)
Measurement Uncertainties & Competing Solutions: VLBA water-megamaser geometric modeling of the sub-parsec nuclear disk combined with infrared Tully-Fisher measurements places M77 at 14.4 ± 1.2 Mpc (47.0 ± 3.9 Mly).

J2000 Equatorial Sky Chart & Culmination Altitude

The chart below plots Cetus A (Messier 77 / NGC 1068 Seyfert 2) at RA 02h 42m 40.71s, Dec -00° 00′ 47.8″ within Cetus, 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 (Cetus) +90° 0° −90° 24h 12h RA 0h Peak Meridian Altitude 50° 40°N Lat 60° 30°S Lat RA: 02h 42m 40.71s Dec: -00° 00′ 47.8″ Epoch: J2000.0 · V = 8.87 mag First-party vector diagram derived from IAU / CDS SIMBAD / Gaia DR3 astrometry.

Astrophysical Context & Structure

Discovered by Pierre Méchain on October 29, 1780, Messier 77 (NGC 1068, radio source Cetus A / 3C 71) is one of the largest and physically most luminous galaxies in the Messier catalog, spanning ~100,000 light-years across from a distance of 47.0 million light-years right on the celestial equator in Cetus. In 1908 Edward Fath at Lick Observatory noticed bright emission lines in M77's nuclear spectrum, and in 1943 Carl Seyfert selected NGC 1068 as the flagship prototype of 'Seyfert galaxies'—spirals hosting intensely luminous active galactic nuclei.

In 1985 Robert Antonucci and Joseph Miller made a discovery in M77 that unified active-galaxy physics: although direct optical spectroscopy shows only narrow emission lines (Type 2 Seyfert), polarized light scattered off electrons above the nucleus reveals broad Doppler-widened emission lines (Type 1 Seyfert) hidden behind an edge-on parsec-scale dusty molecular torus surrounding a ~15-million-solar-mass black hole.

In November 2022 the IceCube Neutrino Observatory at the South Pole announced the detection of ~80 teraelectronvolt (TeV) high-energy astrophysical neutrinos originating from the core of M77—making NGC 1068 the first steady extragalactic neutrino factory identified in the local universe.

Practical Visual Observing Guide

Minimum Instrument60–80 mm telescope
Recommended Magnification100×–200×
Best Evening SeasonAutumn to Early Winter (October–January)
  • Easy to locate just 0.9° east-southeast of the 4.1-magnitude star Delta Ceti (δ Cet), almost Dead-on the celestial equator (Dec −00° 00′ 48″).
  • Because its active Seyfert nucleus and inner starburst ring pack intense light into the central 1.5′, M77 is effortlessly visible in 70 mm scopes and even through moderate suburban light pollution.
  • At 120×–200× in a 150–250 mm telescope, M77 shows a blazing, stellar-like core surrounded by a bright inner lens and a much fainter outer spiral halo; look 10′ northwest for the 11.4-mag edge-on companion galaxy NGC 1055.

Catalog Cross-Identifications & Aliases

Common Aliases: M77 · NGC 1068 · Cetus A · 3C 71 · Arp 37

Cross-Catalog Identifiers for Cetus A (Messier 77 / NGC 1068)
Catalog AuthorityIdentifier
MESSIERM 77
NGCNGC 1068
SIMBADM 77
WIKIDATAQ14014
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Centaurus A (NGC 5128 Active Radio Galaxy)

J2000 coordinates, TRGB/Cepheid distance (12.4 Mly), magnitude 6.84, warped dust lane, relativistic radio lobes, and observing guide for Centaurus A.

Related Object · Canes Venatici

Messier 106 (NGC 4258 Megamaser Anchor)

J2000 coordinates, geometric maser distance (24.7 Mly), magnitude 8.41, anomalous synchrotron arms, Seyfert 2 core, and observing guide for M106.

Reference Guide

Proper Motion, Radial Velocity & Redshift

How astronomers combine tangential proper motion (mas/yr), Doppler radial velocity (km/s), and cosmological redshift (z) to reconstruct 3D space motion.

Reference Guide

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
  • 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