NGC 7689
Galaxy in the constellation Phoenix
From Wikipedia, the free encyclopedia
NGC 7689 is a intermediate spiral galaxy in the constellation of Phoenix. Its velocity with respect to the cosmic microwave background is 1,791±13 km/s, which corresponds to a Hubble distance of 86.2 ± 6.1 Mly (26.42 ± 1.86 Mpc).[1] Also, 13 non-redshift measurements give a closer mean distance of 79.30 ± 1.36 Mly (24.315 ± 0.417 Mpc).[2] It was discovered by Scottish astronomer James Dunlop on 5 September 1826.[3]
| NGC 7689 | |
|---|---|
NGC 7689 imaged by Legacy Surveys | |
| Observation data (J2000 epoch) | |
| Constellation | Phoenix |
| Right ascension | 23h 33m 16.7309s[1] |
| Declination | −54° 05′ 39.692″[1] |
| Redshift | 0.006571±0.0000170[1] |
| Heliocentric radial velocity | 1,970±5 km/s[1] |
| Distance | 79.30 ± 1.36 Mly (24.315 ± 0.417 Mpc)[1] |
| Apparent magnitude (V) | 12.2[1] |
| Characteristics | |
| Type | SAB(rs)cd[1] |
| Size | ~92,300 ly (28.29 kpc) (estimated)[1] |
| Apparent size (V) | 2.9′ × 1.9′[1] |
| Other designations | |
| ESO 192- G 007, IRAS 23305-5422, 2MASX J23331672-5405401, PGC 71729[1] | |
NGC 7689 has a possible active galactic nucleus, i.e. it has a compact region at the center of a galaxy that emits a significant amount of energy across the electromagnetic spectrum, with characteristics indicating that this luminosity is not produced by the stars.[4][5] It is also 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.[6][5]
Supernova
One supernova has been observed in NGC 7689:
- SN 1996al (Type II, mag. 14.0) was discovered by Robert Evans, R. Benton, and S. Beaman on 22 July 1996.[7][8]
Image gallery
NGC 7689 imaged by the Hubble Space Telescope
