Double quasar

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When multiply imaged quasar are quasars called adjacent apparently or actually in the sky. These can be two or more different quasars; these are also referred to as “real” quasars. Alternatively, however, it is also possible and even more likely that it is a matter of multiple imaging by a gravitational lens of a single quasar.

Real double quasars

"Real" double quasars are two different quasars that appear or actually are adjacent in the sky. Quasars that are spatially adjacent are also referred to as a "quasar pair". The first quasar pair was detected by Djorgovsky in 1987. It is the quasar pair OM-076 in the cup . Nine other cases have so far been documented. Because they are the same distance from Earth, they show the same redshift , their different chemical compositions are shown in different electromagnetic spectra .

Since quasars are rare celestial objects, the chances of finding three or more separate quasars in the same location are very small. The first true triple quasar was found in 2007 at the Keck Observatory Mauna Kea , Hawaii . In 2007 a third quasar was discovered in the double quasar LBQS 1429-008. All three quasars have a redshift of z = 2.076, which corresponds to a distance of 10.5 billion light years .

The individual quasars are estimated to be 30–50 kpc apart, which is typical for interacting galaxies.

Multiple images of a quasar

A single quasar can be imaged several times through a gravitational lens . This quasar is called multiply imaged quasar in English . The gravitational lens can produce double, triple or quadruple images of the same quasar. The first object of this kind was discovered in 1979 with Q0957 + 561 . A triple quasar is represented by PG 1115 + 08. A quadruple quasar is the Einstein Cross, also Q2237 + 030, in the constellation Pegasus .

See also

Individual evidence

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  4. Triple quasar QQQ 1429-008 . ESO. Archived from the original on February 8, 2009. Info: The archive link was automatically inserted and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved April 23, 2009. @1@ 2Template: Webachiv / IABot /
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