Great Eruption of Eta Carinae

Date: March 11, 1843 • Location: Rome, Italy

During a period of activity known as the Great Eruption, Eta Carinae (pictured) briefly became the second-brightest star in the night sky.

Eta Carinae, formerly known as η Argus, is a stellar system containing at least two stars with a combined luminosity greater than five million times that of the Sun, located around 7,500 light-years away in the constellation Carina. Previously a 4th-magnitude star, it brightened in 1837 to become brighter than Rigel, marking the start of its so-called "Great Eruption". It became the second-brightest star in the night sky between 11–14 March 1843 before fading well below naked-eye visibility after 1856. In a smaller eruption, it reached 6th magnitude in 1892 before fading again. It has brightened consistently since about 1940, becoming brighter than magnitude 4.5 by 2014.