PKS 1510-089 | |
---|---|
Observation data (J2000.0 epoch) | |
Constellation | Libra |
Right ascension | 15h 12m 50.532s |
Declination | −09° 05′ 59.830″ |
Redshift | 0.360000 |
Heliocentric radial velocity | 107,925 km/s |
Distance | 4.409 Gly |
Apparent magnitude (V) | 16.54 |
Apparent magnitude (B) | 16.74 |
Characteristics | |
Type | Opt var, Sy 1, HPQ |
Notable features | Optically variable blazar |
Other designations | |
LEDA 2828331, INTREF 638, QSO J1512-0906, 4FGL J1512.8-0906, WMAP 207, OHIO R -017, TXS 1510-089, 2E 3390, TIC 79275781, TeV J1512-091, PG 1510-08, PKS 1510-08 |
PKS 1510-089 is a blazar [1] located in the constellation of Libra, categorized as a highly polarized quasar [2] showing fast variations in polarization angles, [3] with a redshift of (z) 0.361. [4] It was first discovered in 1966 as an astronomical radio source during the Parkes Observatory survey in 1966. [5] [6] The radio spectrum of the source appears flat, thus making it a flat-spectrum radio quasar (FRSQ). [4] [7]
PKS 1510-089 is found violently variable on the electromagnetic spectrum according to scientists. It is known to show variations in all wavebands ranging from radio to gamma rays [8] as well as varying in optical brightness. [9] This makes it a key target of several observation campaigns [10] and also by both MAGIC Florian Goebel Telescopes [11] and High Energy Stereoscopic System (HESS). [7] It also shows outbursts, which was detected in 1979, by astronomers via using a 46-meter telescope at the Algonquin Radio Observatory. During this period, the flux density in PKS 1510-089 drastically increased from a low value of 1.5 Jansky (Jy) in 1978 to 4.80 Jy by January 1979 making it the highest recorded flux density during the 12 year observation period. [12]
In March 2009, PKS 1510-089 showed extreme gamma ray activity as observed by the AGILE satellite, which the emission originated, had an average flux of (311 ± 21) x 10−8 photons cm−2 s−1 above 100 MeV. This was then followed by a flaring episode detected in both ultraviolet and near-infrared wavebands. [13] PKS 1510-089 was also observed by Fermi-LAT from August 2008 right up to May 2012, showing several flares when its daily 0.1-300 GeV gamma ray flux exceeded 10−5 photons cm−2 s−1. [14] A short but significant flare was observed in September 2013 although it wasn't high compared to 2009. [15] Between its three quiescent states in 2015, it showed four flares [16]
A powerful complex gamma ray flare was detected in PKS 1510–089 in July 2015. According to multi-frequency optical, radio and gamma ray light curves on the object conducted from 2013 to 2018 as well as analyzing jet kinematic and linear polarization via data from Very Long Baseline Array, a radio flare was discovered trailing the gamma ray flares. This radio flare was shown to have a thick spectrum at the start which then optically becomes thin over a period of time. In additional, two separated emission knots emerging from the radio core during flaring period and linear polarization located near the core, were also detected, prompting astronomers led by Jongho Park to conclude gamma ray flares might arise through the compression of knots caused by a shockwaves inside the core. [17] In additional, a near-infrared flare detected in 2019. [18]
In 2021, PKS 1510-089 underwent a peculiar new state showing a decrease in optical flux, high-energy gamma ray flux in MeV bands and optical polarization degree, reaching zero in 2022. However the X-ray and high-energy gamma ray flux in GeV bands remained constant through the two years. [19] [20]
According to Very Long Baseline interferometry radio imaging at both 6 and 20 cm, the source of PKS 1510-089 shows an unresolved core with a secondary component located 8" towards southeast. When viewed at 1.67 GHz, a dominant component is found lying in a north direction suggesting the core is faint at this frequency. [21]
The jet of PKS 1510-089 is found to move at superluminal speeds. [22] This jet is made up of a milli-arcsecond jet located at position angle -28° and an arcsecond jet with an initial position angle of 55°. Furthermore, the jet is also turbulent with its components moving faster. This causes them to interact with it creating plasma shocks. [23] A counter jet located 0.3 mas from the core, appears to be dominated by shocked emission with a perfect aligned magnetic field. [24] A bright knot of emission was detected in January 2010, which it was found moving down the jet at speeds of 22c while emitting strong gamma ray energy as the outburst in PKS 1510-089 increased. [25]
The supermassive black hole in PKS 1510-089 is known to detect signals of quasi-periodic oscillation. One signal was detected in 2009 during the outburst lasting for five cycles with 3.6 day period. The second signal occurred in 2018 with a period of 92 days until in 2020, when the period evolved to around 650 days. In light of shifting oscillation periods, scientists established a model in order to compare the oscillation behavior of PKS 1510-089 suggesting a binary black hole system with non-asymmetric instability revolving around a central black hole near the innermost orbit. The presence of nearly equidistant magnetic islands in the inner part of the jet, as well as the geometric model which involves a plasma blob in a curved jet moving helically, seems to fit with observations, meaning its period shift was probably caused by a highly eccentric orbit of a secondary black hole. [26]
By measuring hydrogen spectral series and iron emission lines, scientists were able to identify a dark region absorbing emission of the object (broad line region). According to close-up spectroscopies, they found the observed frame region size is 61.1-3.2+4.0 (64.7-10.6+27.1) light-days with an intrinsic line width speed of 1262 ± 247 km s−1. By correlating the two values with the laws of gravitation, they were able to identify a black hole mass of 5.71-0.58+0.62 x 107 Mʘ. [27] However, a study estimated the mass of the black hole to be 1.37 x 109 Mʘ [28] while another study calculates the mass as 5.4 x 108 Mʘ, from the blazar's recorded isotopic luminosity of 2 x 1048 erg s−1. [29]
Based on current measurements, it is proposed PKS 1510-089 has a secondary black hole. [30] It is found orbiting around the primary black hole with a period of 336 ± 14 days and a projected distance of 0.1 parsecs from each other. The mass of the secondary black hole is 1.37 x 107 Mʘ. [28]
4C +71.07 known as S5 0836+71, is a quasar located in the constellation Ursa Major. Based on its high redshift, the object is located 10.7 billion light-years away from Earth and such, classified as a blazar with a flat-spectrum radio source and features a radio jet.
PKS 0537-286, also known as QSO B0537-286, is a quasar located in the constellation Columba. With a redshift of 3.104, the object is located 11.4 billion light years away and belongs to the flat spectrum radio quasar blazar subclass (FSQR). It is one of the most luminous known high-redshift quasars.
PKS 0438-436, also known as PKS J0440-4333, is a quasar located in constellation Caelum. With a high redshift of 2.86, the object is located 11.2 billion light-years from Earth and is classified as a blazar due to its flat-spectrum radio source, (in terms of the flux density as with α < 0.5 and its optical polarization.
PKS 0226-559 known as PMN J0228-5546 is a quasar located in the constellation Horologium. At the redshift of 2.464, the object is roughly 10.6 billion light-years from Earth.
PKS 0451-28, also known as MRC 0451-282, is a quasar located in the constellation of Caelum. Its redshift is 2.55, estimating the object to be located nearly 10.8 billion light-years away from Earth.
PKS 1144-379 also known as PKS B1144-379, is a quasar located in the constellation of Centaurus. At the redshift of 1.048, the object is located nearly 8 billion light-years from Earth.
PKS 1402+044 is a quasar located in the constellation of Virgo. It has a redshift of 3.207, estimating the object to be located 11.3 billion light-years away from Earth.
PKS 0805-07 also known as PMN J0808-0751 and 4FGL J0808.2-0751, is a quasar located in the constellation of Monoceros. With a redshift of 1.83, light has taken at least 10 billion light-years to reach Earth.
PKS 1830-211 is a gravitationally-lensed blazar in the southern constellation of Sagittarius, one of the most powerful such objects known. It has a high redshift (z) of 2.507, an indicator of its significant distance. This flat-spectrum radio quasar (FSRQ) is one of the brightest extraterrestrial radio sources. In visible light, identification of this object is hampered by the galactic plane and an M-type star that lies near the line of sight.
PKS 0736+017 is a blazar located in the constellation of Canis Minor. This object is also a highly polarized compact radio quasar. Its source having a radio spectrum, appears to be flat, making it a flat spectrum radio quasar. It has a redshift of (z) 0.189 and is hosted in a large elliptical galaxy with a half light radius measurement of re = 13 kiloparsecs. The black hole mass in PKS 0736+017 is 7.32+0.89-0.91 x 107 Mʘ based on a full width at half maximum (FWHM) scaling factor and virial relation.
NRAO 530 or PKS 1730-13 is a flat-spectrum radio quasar located in the southern constellation of Serpens. It has a redshift of 0.902. and was first discovered by two astronomers, W.J. Welch and Hyron Spinrad in 1973. It is classified as a blazar because of its optical variability across the electromagnetic spectrum in radio, gamma ray and X-ray bands. This quasar is also further categorized an OVV quasar.
PKS 0208-512 is a blazar located in the southern constellation of Eridanus. It has a redshift of 1.003 and was first discovered in 1975 by astronomers conducting the Parkes 2700 MHz survey in Australia as a bright astronomical radio source. This object is also classified highly polarized with the radio spectrum appearing to be flat, thus making it a flat-spectrum radio quasar.
DA 193 is a blazar located in the constellation of Auriga. It has a high redshift of 2.365. It was first discovered as an unknown astronomical radio source in 1971 by D.G. MacDonell and A.H. Bridle. This is a low polarized quasar containing a classic homogeneous synchrotron self-absorption spectrum. The radio spectrum of this source shows a turnover frequency at 5 GHz and this object has also been referred to as a gigahertz-peak spectrum source.
PKS 1424-418 is a blazar located in the constellation of Centaurus. It has a redshift of 1.522 and was first discovered in 1971 by astronomer Keith Peter Tritton who identified the object as ultraviolet-excessive. This object is also highly polarized with a compact radio source. The radio spectrum of this source appears flat, making it a flat-spectrum radio quasar.
PKS 0537-441 is a blazar located in the constellation of Pictor. It has a redshift of 0.896 and was discovered in 1973 by an American astronomer named Olin J. Eggen, who noted it as a luminous quasar. This is a BL Lacertae object in literature because of its featureless optical spectra as well as both a possible gravitational microlensing and a gravitationally lensed candidate. Its radio source is found compact and is characterized by a spectral peak in the gigahertz range, making it a gigahertz-peaked spectrum source (GPS).
PKS 2004-447 is a narrow-line Seyfert 1 galaxy located in the constellation of Sagittarius. It has a redshift of (z) 0.24 and is the radio-loudest gamma ray emitting AGN known in the southern hemisphere. It was first identified as an astronomical radio source during a very-long-baseline interferometry survey in 1989. The radio spectrum appears to be powerful and compact, making it a compact steep spectrum source. The X-ray emission for this source is described by a simple power-law in the energy range.
PKS 0420-014 is a blazar located in the constellation of Eridanus. This is a high polarized quasar with a redshift of (z) 0.915, first discovered as an astronomical radio source by astronomers in 1975. The radio spectrum of this source appears to be flat, making it a flat-spectrum radio quasar (FRSQ).
PKS 0735+178 is a classical BL Lac object in the northern constellation of Gemini. This is one of the brightest objects of its type in the night sky. It has a redshift of z = 0.424, with a luminosity distance of 7,380 million light-years (2,263 Mpc). PKS 0735+178 is a nearly point-like source with an angular size of a milliarcsecond.
PKS 1622-297 is a blazar located in the constellation of Scorpius. It is one of the brightest objects of its type in the gamma ray region. It has a redshift of (z) 0.815. This blazar was first discovered as a compact astronomical radio source in 1970 by astronomers who were conducting interferometer observations and identified with an optical counterpart in 1984. In addition, the radio spectrum of the source appears flat, making it a flat-spectrum radio quasar (FRSQ).
PKS 0458-020 also known as PKS 0458-02, is a quasar located in the constellation of Orion. It has a redshift of (z) 2.286 and was first identified as an astronomical radio source during the radio survey conducted by Parkes Observatory in 1966. Subsequently the source was shown to display optical behavior before being classfied as a blazar via an optical polarimetry study in 1985. This source also shows radio spectrum appearing to be flat, hence making it a flat-spectrum radio quasar (FRSQ).