In the 19th century, Eta Carinae's apparent brightness increased dramatically and then faded. At least some of the cloud of dust and gas that surrounds the star and obscures it from view is thought to have been released at this time. Astronomers recently discovered that Eta Carinae has one or more companion stars.
Image: A composite optical and X-ray image of the turbulent star Eta Carinae (X-ray: NASA/CXC/GSFC/M.Corcoran et al.; Optical: NASA/STScI)
Will this star explode and form a black hole one day?
Patrick Moore and his guests discuss gamma ray bursts.
Sir Patrick Moore and his guests discuss gamma ray bursts, which are thought to be caused by exploding massive stars. Could the star Eta Carinae emit a gamma ray burst one day?
Prof Brian Cox demonstrates gravity’s force on other planets.
Prof Brian Cox simulates the strength of gravity on other planets through a human centrifuge in Holland.
Coordinates: 10h 45m 03.591s, −59° 41′ 04.26″
Eta Carinae (abbreviated to η Carinae or η Car), formerly known as Eta Argus, is a stellar system containing at least two stars with a combined luminosity over five million times that of the Sun, located around 7500 light-years (2300 parsecs) distant in the direction of the constellation Carina. First recorded as a 4th-magnitude star, it brightened considerably over the period 1837 to 1856 in an event known as the Great Eruption. Eta Carinae became the second-brightest star in the sky between 11 and 14 March 1843 before fading well below naked eye visibility. It has brightened consistently since about 1940, peaking above magnitude 4.5 in 2014. Eta Carinae is circumpolar south of latitude 30°S, so it is never visible north of latitude 30°N.
The two main stars of the Eta Carinae system have an eccentric orbit with a period of 5.54 years. The primary is a peculiar star similar to a luminous blue variable (LBV) that was initially 150–250 M☉ of which it has lost at least 30 M☉ already, and is expected to explode as a supernova in the astronomically near future. This is the only star known to produce ultraviolet laser emission. The secondary star is hot and also highly luminous, probably of spectral class O, around 30–80 times as massive as the Sun. The system is heavily obscured by the Homunculus Nebula, material ejected from the primary during the Great Eruption. It is a member of the Trumpler 16 open cluster within the much larger Carina Nebula. Although unrelated to the star or Nebula, the weak Eta Carinids meteor shower has a radiant very close to Eta Carinae.