NGC 491

NGC 491
NGC 491 imaged by the Hubble Space Telescope, showing its spiral arms
Observation data (J2000 epoch)
Constellation	Sculptor
Right ascension	01^h 21^m 20.4504^s[1]
Declination	−34° 03′ 48.096″[1]
Redshift	0.012902±0.0000330[1]
Heliocentric radial velocity	3,868±10 km/s[1]
Distance	203.09 ± 7.02 Mly (62.267 ± 2.152 Mpc)[1]
Apparent magnitude (V)	13.21[1]
Characteristics
Type	SB(rs)b[1]
Size	~91,900 ly (28.17 kpc) (estimated)[1]
Apparent size (V)	1.4′ × 1.0′[1]
Other designations
ESO 352- G 053, GC 279, IRAS 01190-3419, MCG -06-04-011, PGC 4914[1]

NGC 491 is a barred spiral galaxy in the constellation Sculptor.^[2][1] Its velocity with respect to the cosmic microwave background is 3,635±19 km/s, which corresponds to a Hubble distance of 174.9 ± 12.3 Mly (53.62 ± 3.77 Mpc).^[1] However, nine non-redshift measurements give a farther mean distance of 203.09 ± 7.02 Mly (62.267 ± 2.152 Mpc).^[3] It was discovered by British astronomer John Herschel on 25 September 1834.^[4]

NGC 491 is a Seyfert II galaxy, i.e. it has a quasar-like nucleus with very high surface brightnesses whose spectra reveal strong, high-ionisation emission lines, but unlike quasars, the host galaxy is clearly detectable.^[5]

Supernova

One supernova has been observed in NGC 491: SN 2025yjt (Type II, mag. 17.827) was discovered by ATLAS on 24 September 2025.^[6]

See also

• NGC 7001
• List of NGC objects (1–1000)

References

1. "Results for object NGC 0491". NASA/IPAC Extragalactic Database. NASA and Caltech. Retrieved 2017-06-04.
2. Rojas, Sebastián García. "Galaxy NGC 491 - Galaxy in Sculptor Constellation · Deep Sky Objects Browser". DSO Browser. Archived from the original on 2017-10-02. Retrieved 2017-06-04.
3. "Distance Results for NGC 0491". NASA/IPAC Extragalactic Database. NASA. Retrieved 25 September 2025.
4. "New General Catalog Objects: NGC 450 - 499". cseligman.com. Retrieved 2017-06-04.
5. "NGC 491". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 25 September 2025.
6. "SN 2025yjt". Transient Name Server. IAU. Retrieved 25 September 2025.

External links

• NGC 491 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images