Eta Carinae: Our crazy neighbor

Updated 11:59 AM ET, Wed February 15, 2012
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Eta Carinae is a binary star system that lives inside the Carina Nebula, a region seen here. This new image, captured this month by the European Southern Observatory in Chile, reveals a breathtaking landscape of gas, dust and young stars. ESO
Located inside the blue homunculus nebula seen here, Eta Carinae is mind-bogglingly huge -- about 120 times larger than our sun. Relatively close -- about 7,500 light years from Earth -- it's also doomed to explode in a supernova sometime during the next million years. Learning more about Eta Carinae could teach us more about the evolution of stars and how the most basic elements in the universe are formed. NASA/CXC/GSFC/M.Corcoran
During the mid-1800s, astronomers observed what has become known as the Great Eruption -- a mysterious event that vaulted Eta Carinae among the night sky's brightest stars, before its brightness faded a few years later. The star spit out massive amounts of material, and scientists still don't know exactly why. The ejected material formed a homunculus nebula, seen here, around the star. ESO
In 2005 scientists first detected direct evidence that Eta Carinae is a binary system with a much smaller companion star circling it in an eliptical orbit. Some scientists suspect the smaller star may have contributed to the Great Eruption. Astronomers captured this infrared narrow K-band image of Eta Carinae in 2003. ESO
Recently discovered "light echoes" from the Great Eruption reveal new details which cast doubt on a popular theory explaining the event. This Space Technology Science Institute image from March 2003 shows a field of stars, seen as bright, rounded, points of light south of Eta Carinae with no visible light echoes. Courtesy Space Telescope Science Institute
Here's the same area nearly eight years later in 2011. Light echoes in the image are visible as extended, nebulous features. "They are faint compared to the stars, and therefore they are not easy to find," says astrophysicist Armin Rest, who first observed the phenomenon. Courtesy Space Telescope Science Institute