Cygnus X-1

Cygnus X-1 (abbreviated Cyg X ( R ) 1) is an X-ray binary star in the constellation Cygnus (Latin Cygnus ). In the X-ray range, the radiation of energy moves in the order of some ten thousand solar luminosities. The name of Cygnus X-1 arises from the fact that this is the first discovered X-ray object ( engl. X -ray) in the constellation Cygnus is.

One of the two objects is a black hole of 14.8 ± 1 solar masses and an event horizon with an estimated 26 kilometers radius.

The main star is a blue giant called HD 226,868th This has the 300 400,000 times brighter than the sun, the 15 -17 -fold in diameter and a weight of around 40 ± 10 solar masses. The two binary components of Cyg X-1 orbit each other in 5.6 days., The distance is only about twice as large as the radius of the main star. It is believed that the Blue Giant by the continuous stellar wind in 400,000 years loses a mass of the order of the sun. The age of the constellation is estimated at 5 million years.

The X-ray radiation arises from the fact that the mass of the main star is drawn to the black hole, where it forms an accretion disk, which heats up due to friction at several million degrees, and thus emits X-rays.

The assumption that this is a strong X-ray source to have existed since 1962 and was finally proven in 1970 with the help of the Uhuru X-ray telescope. From 1974, was suspected due to the extremely short-term variations of the X-ray intensity and other characteristics that Cygnus X-1 is a double star with an extremely compact object. Because of the mass exudes a neutron star, so everything points to a black hole. Furthermore, the impact of the matter on a neutron star as a separate X-ray outburst would be visible. In 2001 was detected by means of the two space telescopes Hubble and Chandra that matter suddenly disappears. This is explained by the immersion into the event horizon. Combined with observations by Chandra and XMM- Newton were initially rotated that the black hole can not be measured or unusually slow. Later research revealed a very rapid rotation of 790/Sekunde.

The distance from Cygnus X-1 could initially be difficult to accurately determine because at such large distances, the parallax of the object in the order of magnitude of the possible measurement error was. First of 6500-8200 light-years were accepted; more detailed studies in 2011 laid the distance fixed at about 6100 light years.

Reception

The Cygnus X -1 duology the Canadian progressive rock band Rush is about a story around the black hole.