| CTA 102 | |
|---|---|
 SDSS image of CTA 102. | |
| Observation data (Epoch J2000) | |
| Constellation | Pegasus |
| Right ascension | 22h 32m 36.4s [1] |
| Declination | +11° 43′ 51s″ [1] |
| Redshift | 1.037 [1] |
| Distance | 8 billion light years [2] |
| Other designations | |
| CTA-102, Q2230+11, QSR B2230+114, QSO J2232+1143, 4C +11.69, PGC 2819036 | |
| See also: Quasar, List of quasars | |
CTA 102, also known by its B1950 coordinates as 2230+114 (QSR B2230+114) and its J2000 coordinates as J2232+1143 (QSO J2232+1143), is a blazar-type quasar discovered in the early 1960s by a radio survey carried out by the California Institute of Technology. [3] It has been observed by a large range of instruments since its discovery, including WMAP, EGRET, GALEX, VSOP and Parkes, [1] and has been regularly imaged by the Very Long Baseline Array since 1995. [4] It has also been detected in gamma rays, and a gamma-ray flare has been detected from it. [5]
In 1963 Nikolai Kardashev proposed that the then-unidentified radio source could be evidence of a Type II or III extraterrestrial civilization on the Kardashev scale. [3] Follow-up observations were announced in 1965 by Gennady Sholomitskii, who found that the object's radio emission was varying; [6] a public announcement of these results on April 12, 1965, caused a worldwide sensation. [7] The idea that the emission was caused by a civilization was rejected when the radio source was later identified as one of the many varieties of a quasar. [3]
The American folk rock band The Byrds whimsically reflected the original view that CTA-102 was a sign of extraterrestrial intelligence in their song "C.T.A.-102" from their 1967 album Younger Than Yesterday . [8]
In late 2016 CTA 102, usually glowing around magnitude +17, had a bright outburst in visible light to magnitude +11 (~250 times brighter than usual). [9] [10] This likely was the most luminous blazar state ever observed, [11] with an absolute magnitude in excess of -32.
A new outburst began in December 2017, with increased gamma-ray [12] and optical activity. [13] As of 22 December 2017, it has reached magnitude +14. [14]
CTA 102 displays a radio structure mainly made of a radio core and two other components. There is also a double knot feature. [15] Additionally, it also has two radio lobes described having flux densities of 170 and 75 mJy, with a jet found as curved according to high resolution imaging by Very Long Baseline interferometry at 15 GHz. This jet contains jet components moving with apparent velocities of 15.4 ± 0.9c. [16]
The quasar is also classified to be highly polarized with a flat radio spectrum, and such belongs to a classification of optically violent variable quasars. [17] [18]
