NGC 128 | |
---|---|
Observation data (J2000 epoch) | |
Constellation | Pisces |
Right ascension | 00h 29m 15.047s[1] |
Declination | +02° 51′ 50.60″[1] |
Redshift | 0.01466[1] |
Heliocentric radial velocity | 4363 km/s[1] |
Distance | 190 Mly (58 Mpc)[2] |
Apparent magnitude (V) | 11.63[3] |
Apparent magnitude (B) | 12.65[3] |
Characteristics | |
Type | S0[1] |
Other designations | |
UGC 292, MCG +00-02-051, PGC 1791[1] |
NGC 128 is a lenticular galaxy in the constellation Pisces. It is approximately 190 million light-years from the Sun and has a diameter of about 165,000 light-years.[2]
NGC 128 was discovered by astronomer William Herschel on 25 December 1790 using a reflecting telescope with an aperture of 18.7 inches. At the time of discovery, its coordinates were recorded as 00h 22m 05s, +87° 54.6′ -20.0″.[4] It was later observed by John Herschel on 12 October 1827.[2]
The galaxy is described as "pretty bright", "very small" with a "brighter middle". It is approximately 165,000 light years in diameter and is elongated.[5][2] The galaxy is famous for its (peanut shell)-shaped bulge, and in 2016 it was discovered that there are two such nested structures, possibly associated with two stellar bars.[6]
NGC 128 is the largest member, and the namesake of, the NGC 128 group which also includes the galaxies NGC 127 and NGC 130. NGC 128 has a strong tidal bridge with NGC 127 and there is evidence of interaction between all three galaxies in the group. NGC 128 has a noticeable peanut shape that is likely to be caused by gravitational effects of the other two galaxies.[7]