Q: What is Eta Carinae?
A: Eta Carinae is a binary star located within the Carina constellation. This star is the primary cause of the glow produced by the surrounding Eta Carinae nebula, a vast and impressive region of space. Despite its significant distance of 7,500 light years, the Eta Carinae nebula fills an area of the sky larger than the full moon.
In recent years, Eta Carinae has been steadily increasing in brightness. Although it was too dim to be observed directly in the 1990s, it is now visible to the unaided eye. During the 1800s, Eta Carinae went through a particularly spectacular brightening, becoming the second brightest star in the night sky, outshone only by Sirius (which is a 'mere' 8.6 light years away).
Eta Carinae represents the potential to consistently 'outdo itself' and shine more brightly than ever before.
Among visible stars, Eta Carinae is considered the most likely candidate for a supernova, something which could occur at any time. When this eventually does take place, Eta Carinae would, for a time, shine so brightly that one would be able to read by its light at night, and see it shining in the sky during the day!