| NGC 6902 | |
|---|---|
 | |
| Observation data (J2000epoch) | |
| Constellation | Sagittarius |
| Right ascension | 20h 24m 28.067s[3] |
| Declination | −43° 39′ 12.42″[3] |
| Redshift | 0.009300±0.000023[4] |
| Heliocentric radial velocity | 2793.9 km/s[5] |
| Distance | 124 Mly (38.0 Mpc)[6] |
| Group orcluster | LGG 434 |
| Apparent magnitude (V) | 10.93±0.18[6] |
| Apparent magnitude (B) | 11.64±0.18[6] |
| Characteristics | |
| Type | SA(r)b[6] |
| Size | ~334,800 ly (102.64 kpc) (estimated) |
| Apparent size (V) | 3.55′ × 2.69′[7] |
| Other designations | |
| Gaia DR2 6678974930431764096,IRAS 20210-4348, F20210-4348,2MASX J20242813-4339127,NGC 6902,IC 4948,LEDA 64632,MCG -07-42-002,PGC 64632[8] | |
NGC 6902 is an unbarredspiral galaxy located in the southern constellation ofSagittarius at an approximate distance of 124 millionlight-years (38.0 Mpc).[6] NGC 6902 was discovered on September 2, 1836 by English astronomerJohn Herschel.[9] In hisNew General Catalogue, Danish astronomerJ. L. E. Dreyer described it as faint, considerably small, round, brighter middle.[10][11] It is a member of the small NGC 6092 group of galaxies; theLGG 434 group.[9]
Themorphological classification of NGC 6902 is SA(r)b,[6] indicating an unbarred spiral galaxy (SA) with an inner ring (r) and somewhat tightly woundarms (b). As the two arms extend outward, they transition into a complex system of filamentary arms. The galaxy has anangular size of3.55′ × 2.69′ in the optical band.[7] Thegalactic plane is inclined at an angle of 38±5° to the line of sight from the Earth. NGC 6902 has a high abundance of neutral hydrogen; about three times greater than a typical galaxy of this class.[12] The ring structure is undergoing extensive star formation. Although classed as unbarred, there is a small bar of stars inside the ring.[9]
Onesupernova has been observed in NGC 6902: SN 2024uwq (type Ic-BL, mag. 17.4).[13]
Media related toNGC 6902 at Wikimedia Commons
