Eta Carinae is a sixth- magnitude star located between 8,000 and 10,000 light-years away in the constellation Carina (the keel) which lies in the southern hemisphere. It was first cataloged in 1677 by astronomer extraordinaire Edmund Halley. The star originally attracted attention due to its extreme variability. Halley cataloged it as a fourth-magnitude star, but has varied widely and wildly, ranging from 8th magnitude all the way to -1 magnitude, outshining every other star in the sky except for Sirius. The star is presently in the middle of a rapid brightening period.
Further investigation shown that Eta Carinae is possibly one of the most remarkable objects in the sky. It is the most massive star known, with a mass between 120 and 150 solar masses, and is thought to be one of the most massive stars in the entire universe. It emits 5 million times the energy of the Sun, 99% of which in the form of infrared radiation, making it the brightest object in the sky on the 10-20 micron range. Hubble Space Telescope pictures taken in 1995 shown that approximately 150 years ago, it ejected a large amount of matter, which form bipolar lobes and a thin equatorial disk (for a truly breath-taking picture, see http://oposite.stsci.edu/pubinfo/pr/96/23.html). Finally, due to its gargantuan size and recent, unexplainable, doubling in brightness, most astronomers believe that the years of life remaining to the star are numbered in the low thousands, with a chance of dying virtually any day now ("any day now" in its literal meaning, as opposed to the usual astronomical usage). No one is certain what happens when a star of that size dies, but most theories suggest that it will most likely involve a hypernova, black hole formation, and possibly a gamma-ray burst. Note that a gamma-ray burst at a distance of 8,000 light-years will not be harmful people and electronics protected by the atmosphere, but you certainly don't want to be vacationing on the Moon at the time.