The Eta Carina Nebula is one of the most spectacular objects in the sky, and the
brightest of all the emission nebulae. It appears as an oval patch in the Milky Way
within the southern constellation Carina, brighter and 4 times larger than the
Orion Nebula. It is 260 light years across, and 8000 light years from earth.

The main source of power lighting up the nebula is the star Eta Carina. This star
seemed to be an unremarkable 4th magnitude star when first catalogued in the 17th
century. But it soon began brightening, and by 1827 it was the 2nd brightest of all
the stars, second only to Sirius. It has now dimmed again, so that it is just a bit
too dim to see with the naked eye.

In 1843, Eta Carina began a massive outburst, and over a few years it emitted as much
light as a typical supernova, though the star was not blown apart. Eta Carina is a rare
star, with 100-150 times the mass of the sun; there are probably only a few dozen stars like
this in the whole galaxy. Eta Carina also puts out 4 million times as much energy as
the sun. In 6 seconds, Eta Carina produces more energy than the sun does in
an entire year. Its massive size and instability make Eta Carina a prime candidate for
a supernova explosion.

This image was taken while working and traveling in Tanzania.
The image was published in Sky & Telescope, August 2009, page 71.

Image data:
Telescope: William Optics 66mm
Mount: Meade LXD-55
Camera: Canon 350 XT (unmodified)
Exposure: ISO 800, 30 seconds x 80
Location: Iringa, Tanzania