| NGC 1277 | |
|---|---|
 NGC 1277 as seen by theHST | |
| Observation data (J2000epoch) | |
| Constellation | Perseus |
| Right ascension | 03h 19m 51.5s[1] |
| Declination | 41° 34′ 25″[1] |
| Redshift | 0.016898[1] |
| Heliocentric radial velocity | 5066 km/s[1] |
| Galactocentric velocity | 5168 km/s[1] |
| Distance | 73 Mpc (240 Mly)[2] |
| Group orcluster | Perseus Cluster[3][2] |
| Apparent magnitude (V) | 14.66[1] |
| Characteristics | |
| Type | S0^+, pec[1] |
| Size | ~52,700 ly (16.16 kpc) (estimated)[1] |
| Apparent size (V) | 1.0 x 0.4[1] |
| Other designations | |
| PGC 12434,LGG 088 | |
References:[1] | |
NGC 1277 is alenticular galaxy in the constellation ofPerseus. It is a member of thePerseus Cluster of galaxies and is located approximately 73 Mpc (megaparsecs)[2] or 220 millionlight-years from theMilky Way. It has an apparent magnitude of about 14.7. It was discovered on December 4, 1875 byLawrence Parsons, 4th Earl of Rosse.
NGC 1277 has been called a "relic of the early universe" due to its stars being formed during a 100 million year interval about 12 billion years ago. Stars were formed at a rate of 1000 times that of theMilky Way galaxy's formation rate in a short burst of time. After this process of stellar formation ran its course,NGC 1277 was left populated with metal-rich stars that are about 7 billion years older than the Sun.[2] It is still uncertain whether or notNGC 1277 is a "relic galaxy"; current studies are still researching the possibility.[4][5] However, observations withHubble Space Telescope indicate that NGC 1277 lacks metal-poor globular clusters, suggesting that it has accreted little mass over its lifetime and supporting the relic galaxy hypothesis.[6]
NGC 1277 has a very unusual rotation curve that suggests that it contains very littledark matter.[7]
Initial observations made using theHobby–Eberly Telescope at Texas'sMcDonald Observatory suggested the presence of ablack hole with a mass of about1.7×1010 M☉ (17 billion solar masses), equivalent to 14% of the total stellar mass of the galaxy, due to the motions of the stars near the center of the galaxy.[8] This resulted in the initial claim that the black hole in NGC 1277 isone of the largest known in relation to the mass of its host galaxy.
A follow-up study,[9] based on the same data and published the following year, reached a very different conclusion. The black hole that was initially suggested at1.7×1010 M☉ was not as massive as once thought. The black hole was estimated to be between 2 and 5 billion solar masses. This is less than a third of the previously estimated mass, a significant decrease. Models with no black hole at all were also found to provide reasonably good fits to the data, including the central region.
Subsequent investigations employedadaptive optics to acquire a better estimate of the mass of the black hole.[4][5]One group made observations using the Gemini Near Infrared Integral Field Spectrometer to better determine the mass of the black hole at the center of NGC 1277.[4] The group used similar models to that of van den Bosch, but with higher spatial resolution. After using stellar dynamics and luminosity models to estimate the mass of the black hole, they came to a mass of4.9×109 M☉, similar to the estimate from the follow-up study done by Emsellem,[9] which estimated a mass between 2–5 billion solar masses. More recently, a new group[5] made observations using the largerKeck Telescope with superior spatial resolution, and calculated that a black hole with mass1.2×109 M☉ fits best. Moreover, this value is an order of magnitude smaller than first reported by van den Bosch,[8] and was noted to probably be an upper limit due to the edge-on rotating disk in NGC 1277.
Media related toNGC 1277 at Wikimedia Commons
