The Eta Carinae system is comprised of two stars – one being a giant, unstable star at the final stages of its lifetime. The 1840′s event is thought to be a “supernova impostor” event – an event which appears similar to a supernova, but does not destroy the host star. While astronomers of the 19th century weren’t able to see the 1840′s outburst in detail, modern astronomers are able to study its effects.
The outburst detected in the 1840′s threw out tremendous amounts of matter, which is now known as the Homunculus Nebula. The image shown above was taken with the Advanced Camera for Surveys High Resolution Channel, on-board the Hubble Space Telescope. What is interesting about this nebula is that the ejected material wasn’t expelled uniformly.
Eta Carinae is one of a handful of stars near Earth that are nearing the end of their lives. The end stage for Eta Carinae and others will be a brilliant supernova some time in the near future. Of course, cosmically speaking, “near future” could be tomorrow, or even a million years from now. Eta Carinae’s supernova will be an impressive sight, as it’s much closer than the brightest supernova currently recorded, which was 200 light-years from Earth!