Circinus X-1
| Circinus X-1 data | |
|---|---|
| Constellation | Circle |
| Position ( equinox : J2000.0 ) | |
| Right ascension | 15h 20m 40.8s |
| declination | −57 ° 10 ′ 00 ″ |
| X-ray source | |
| Type | Low-mass X-ray binary star, highly variable X-ray source (compact, non-pulsed) |
| Catalog names | 4U 1516-569, 1RXS J152040.8-571007, GX 292 + 00 |
| Double star system | |
| distance | approx. 20,000 light years |
| Period of circulation | 16.6 days |
| Optical / stellar component: BR Circini |
|
| Spectral class | |
| Apparent brightness | |
| Dimensions | approx. 3 to 5 solar masses |
| Compact component: Circinus X-1 neutron star | |
| Dimensions | approx. 1 solar mass |
Circinus X-1 (short: Cir X-1 ) is an X-ray binary star . Discovered in 1971, the system is 31,000 light years away and is located in the constellation Circle .
The binary star system consists of an ordinary star with about three to five times the mass of the sun and a neutron star . Here the neutron star, which is slightly more massive than our sun , attracts matter from its partner. The accretion disk around the neutron star causes the X-rays. Both stars will likely orbit each other in a highly elliptical orbit in 16.6 days .
A jet was discovered at Cir X-1 moving at 99.8% the speed of light. It was previously believed that only black holes could create a relativistic jet.