NGC 7769
Galaxy in the constellation Pegasus
From Wikipedia, the free encyclopedia
NGC 7769 is an unbarred spiral galaxy in the constellation of Pegasus. Its velocity with respect to the cosmic microwave background is 3855 ± 25 km/s, which corresponds to a Hubble distance of 56.85 ± 4 Mpc (~185 million light-years).[1] It was discovered by German-British astronomer William Herschel on 18 September 1784.[2]
| NGC 7769 | |
|---|---|
NGC 7769 imaged by SDSS | |
| Observation data (J2000 epoch) | |
| Constellation | Pegasus |
| Right ascension | 23h 51m 03.9592s[1] |
| Declination | +20° 09′ 01.508″[1] |
| Redshift | 0.014046[1] |
| Heliocentric radial velocity | 4211 ± 2 km/s[1] |
| Distance | 185.4 ± 13.0 Mly (56.85 ± 4.00 Mpc)[1] |
| Group or cluster | NGC 7771 Group (LGG 483) |
| Apparent magnitude (V) | 12.0[1] |
| Characteristics | |
| Type | (R)SA(rs)b[1] |
| Size | ~176,600 ly (54.14 kpc) (estimated)[1] |
| Apparent size (V) | 3.2′ × 2.7′[1] |
| Other designations | |
| HOLM 820C, IRAS 23485+1952, 2MASX J23510396+2009014, UGC 12808, MCG +03-60-030, Mrk 9005, PGC 72615, CGCG 455-054[1] | |
The galaxies NGC 7769, together with NGC 7770 and NGC 7771, are listed together as Holm 820 in Erik Holmberg's A Study of Double and Multiple Galaxies Together with Inquiries into some General Metagalactic Problems, published in 1937.[3] NGC 7769 also is listed as part of the five-member NGC 7771 Group (also known as LGG 483), which contains the 3 galaxies from Holm 820, NGC 7786, and UGC 12828.[4]
NGC 7769 is a LINER galaxy, i.e. it has a type of nucleus that is defined by its spectral line emission which has weakly ionized or neutral atoms, while the spectral line emission from strongly ionized atoms is relatively weak.[1]
Supernovae
Three supernovae have been observed in NGC 7769:
- SN 2019iex (Type II, mag. 17.6) was discovered by the Searches After Gravitational-waves using ARizona Observatories (SAGUARO) project on 26 June 2019.[5]
- SN 2022mxv (Type II, mag. 18.249) was discovered by ATLAS on 18 June 2022.[6]
- SN 2022aedu (Type II, mag. 16.9) was discovered by Kōichi Itagaki on 31 December 2022.[7]
