| PKS 1302−102 | |
|---|---|
| Observation data(EpochJ2000.0) | |
| Constellation | Virgo[1] |
| Right ascension | 13h 05m 33.01498s[2] |
| Declination | −10° 33′ 19.4266″[2] |
| Redshift | 0.2784[1] |
| Distance | 3.5×10 |
| Type | FSRS, FSRQ, FSQ, QSO, E4[2][1] |
| Apparent magnitude (V) | 14.9[1] |
| Other designations | |
| PG 1302−102, PG 1302−103,ICRF J130533.0−103319,PKS 1302−102, PKS 1302−103, PKSJ1305−1033, PKSB1302−102,QSOJ1305−1033, QSOB1302−1017,[2]PGC 4662778[1] | |
| See also:Quasar,List of quasars | |
PKS 1302−102 is aquasar in theVirgo constellation, located at a distance of approximately 1.1Gpc (around 3.5 billion light-years).[1] It has anapparent magnitude of about 14.9 mag in theV band with aredshift of 0.2784.[1] The quasar is hosted by a brightelliptical galaxy,[3] with two neighboring companions at distances of 3 kpc and 6 kpc. The light curve of PKS 1302−102 appears to be sinusoidal with an amplitude of 0.14 mag and a period of 1,884 ± 88 days, which suggests evidence of asupermassive black hole binary.[4]
PKS 1302−102 was selected from theCatalina Real-Time Transient Survey as one of 20 quasars with apparent periodic variations in the light curve. Of these quasars, PKS 1302−102 appeared to be the best candidate in terms of sinusoidal behavior and other selection criteria, such as data coverage of more than 1.5 cycles in the measured period.[4] One plausible interpretation of the apparent periodic behavior is the possibility of twosupermassive black holes (SMBH) orbiting each other with a separation of approximately 0.1 pc in the final stages of a 3.3 billion year old galaxy merger. If this turns out to be the case, it would make PKS 1302−102 an important object of study to various areas of research, includinggravitational wave studies and the unsolvedfinal parsec problem in a merger of black holes.
Other explanations, of lesser likelihood, to the observed sinusoidal periodicity include a hot spot on the inner part of the black hole's accretion disk and the possibility of a warped accretion disk which partially eclipses in the orbit around a single SMBH.[4] However, it also remains possible that the periodic behavior in PKS 1302−102 is indeed just a random occurrence in the light curve of an ordinary quasar, asspurious nearly-periodic variations can occur over limited time periods as part of stochastic quasar variability.[5] Further observations of the quasar could either promote true periodicity or rule out a binary interpretation, especially if the measured light curve randomly diverges from the sinusoidal model.[5]
