Ever since 1841, when the until then inconspicuous southern star Eta Carinae underwent a spectacular outburst, astronomers have wondered what exactly is going on in this unstable giant star. However, due to its considerable distance – 7,500 light-years – details of the star itself were beyond observation.

This star is known to be surrounded by the Homunculus Nebula, two mushroom-shaped clouds ejected by the star, each of which is hundreds of times larger than our solar system.



Now, for the first time, infrared interferometry with the VINCI instrument on ESO’s Very Large Telescope Interferometer (VLTI) enabled an international team of astronomers [1] to zoom-in on the inner part of its stellar wind.



For Roy van Boekel, leader of the team, these results indicate that “the wind of Eta Carinae turns out to be extremely elongated and the star itself is highly unstable because of its fast rotation.”



A monster in the southern sky



Eta Carinae, the most luminous star known in our Galaxy, is by all standards a real monster: it is 100 times more massive…



Full story here.