NGC 797
Galaxy in the constellation Andromeda
From Wikipedia, the free encyclopedia
NGC 797 (also known as NGC 797 NED02) is a barred spiral galaxy in the constellation of Andromeda. Its velocity with respect to the cosmic microwave background is 5,414±17 km/s, which corresponds to a Hubble distance of 260.4 ± 18.3 Mly (79.85 ± 5.60 Mpc).[1] However, three non-redshift measurements give a much farther mean distance of 369.64 ± 4.35 Mly (113.333 ± 1.333 Mpc).[2] It was discovered by German-British astronomer William Herschel on 21 September 1786.[3][4]
| NGC 797 | |
|---|---|
NGC 797 imaged by Pan-STARRS | |
| Observation data (J2000 epoch) | |
| Constellation | Andromeda |
| Right ascension | 02h 03m 27.9624s[1] |
| Declination | +38° 07′ 00.823″[1] |
| Redshift | 0.018860±0.0000130[1] |
| Heliocentric radial velocity | 5,654±4 km/s[1] |
| Distance | 369.64 ± 4.35 Mly (113.333 ± 1.333 Mpc)[1] |
| Group or cluster | CGPG 0200.4+3753 |
| Apparent magnitude (V) | 13.1[1] |
| Characteristics | |
| Type | SAB(s)a[1] |
| Size | ~210,400 ly (64.51 kpc) (estimated)[1] |
| Apparent size (V) | 1.9′ × 1.4′[1] |
| Other designations | |
| CGPG 0200.4+3753 NED02, NGC 797 NED02, UGC 1541, MCG +06-05-078 NED02, PGC 7832, CGCG 522-105 NED02, VV 428 NED02[1] | |
In 1971, Fritz Zwicky and his daughter, Margrit A. Zwicky, published Catalogue of Selected Compact Galaxies and of Post-Eruptive Galaxies, which showed that NGC 797 has an elliptical compact companion galaxy at the tip of its southwest spiral arm, and catalogued the galaxy pair as CGPG 0200.4+3753.[5] The companion galaxy is catalogued as NGC 0797 NED01 and PGC 212899, among other designations.
NGC 797 and NGC 801 form a galaxy pair, and the distance between the two is about 150 kiloparsecs.[6]
