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). Additionally, one non-redshift measurement gives a farther distance of 272 Mly (83.3 Mpc). 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)."
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.
