NGC 391

NGC 391 is an unbarred lenticular galaxy located in the constellation Cetus. Its velocity with respect to the cosmic microwave background is 5,022±23 km/s, which corresponds to a Hubble distance of 241.6 ± 17.0 Mly (74.07 ± 5.20 Mpc).^[1] Additionally, one non-redshift measurement gives a farther distance of 272 Mly (83.3 Mpc).^[2] It was discovered by American astronomer George Bond on January 8, 1853. It was described by Dreyer as "faint, small, mottled but not resolved (Auwers 9)."^[3]

NGC 391
SDSS image of NGC 391
Observation data (J2000 epoch)
Constellation	Cetus
Right ascension	01h 07m 22.5865s[1]
Declination	+00° 55′ 33.403″[1]
Redshift	0.017829±0.00000667[1]
Heliocentric radial velocity	5,345±2 km/s[1]
Distance	241.6 ± 17.0 Mly (74.07 ± 5.20 Mpc)[1]
Apparent magnitude (V)	14.1g[1]
Characteristics
Type	(R')SA0−:[1]
Size	~94,800 ly (29.08 kpc) (estimated)[1]
Apparent size (V)	0.89′ × 0.75′[1]
Other designations
2MASX J01072255+0055331, UGC 693, MCG +00-03-075, PGC 3976, CGCG 384-077[1]

Supernova

One supernova has been observed in NGC 391: SN 2025rat (Type Ia, mag. 19.9454) was discovered by Zwicky Transient Facility on 11 July 2025.^[4]

See also

• List of NGC objects (1–1000)