| UGC 9799 | |
|---|---|
| The radio galaxy UGC 9799. | |
| Observation data (J2000 epoch) | |
| Constellation | Serpens |
| Right ascension | 15h 16m 44.50s [1] |
| Declination | +07° 01′ 18.07″ [1] |
| Redshift | 0.034547 [1] |
| Heliocentric radial velocity | 10357 km/s [1] |
| Distance | 543 Mly |
| Group or cluster | Abell 2052 |
| Apparent magnitude (V) | 14.17 |
| Characteristics | |
| Type | cD; E, Sy2, LEG |
| Size | ~331,500 ly (101.65 kpc) (estimated) [1] |
| Other designations | |
| 3C 317, 4C +07.40, CoNFIG 214, CGCG 049-090, CTA 067, DA 379, GIN 419, LHE 388, MCG +01-39-012, PKS 1514+07, PGC 54526 [1] | |
UGC 9799 also known as 3C 317, is a radio galaxy located in the constellation of Serpens. The redshift of the galaxy is (z) 0.034 [1] estimating a light-travel time distance of 543 million light-years [2] and it was first discovered as an astronomical radio source by astronomers in 1959. [3] It is classified as a type-cD galaxy [4] [5] and is the brightest cluster galaxy of the galaxy cluster, Abell 2052. [6]
UGC 9799 is categorized as an elliptical galaxy with a slightly elongated appearance but its nucleus is found unresolved. There is an ultraviolet filament present in the galaxy four kiloparsecs to the south from the nucleus region. This evidence hints the suggestion of star formation activity triggered by a galaxy merger of an nearby satellite galaxy. [7] [6] Imaging made by Hubble Space Telescope (HST), found the core isophotes seems extending towards a dark band feature suggested to be a diffused dust lane. [8] A secondary nucleus is likely present in UGC 9799. [9]
The galaxy contains a radio source that has a steep radio spectrum. When observed with Very Large Array (VLA), the structure is mainly irregular and its spectra index is mainly 0.8 below the frequencies of 200 MHz but gets much steeper upon reaching more than 750 MHz. [10] A compact radio core is found at the center of the source; however there are no signs that the core is significantly variable. There is a large bipolar structure surrounding the core region which in turn, is enveloped inside a halo. There is also a loop structure linking together with its northern radio lobe and a plume feature. [11] New observations at 4.9 GHz, found the radio morphology is classified as S-shaped with two short jet features that have a bending angle of 5 milliarcseconds from the radio peak. At 8.3 GHz, these jets are shown to have an alignment to around -32°. [12]
Studies published in 1995 and in 2017, have found the presence of globular clusters inside UGC 9799 based on imaging. [13] [14] Further evidence also found there are 46,000 clusters in total, making these the largest amount found so far. [15] A supermassive black hole mass of 108 Mʘ has been estimated for the galaxy. [16]