Found: Milky Way's Second-Brightest Star

July 16, 2008 -- If you can't be the brightest star out of 100 billion, second brightest ain't bad. That's just what astronomers have found, hidden in a flowery dust cloud near the center of the Milky Way: the second-brightest star (and one of the most dangerous) in our home galaxy.

What's being called the Peony Nebula star is calculated to be as bright as 3.2 million suns. That's approaching the supremacy of the brightest known star in the galaxy, Eta Carina, which blazes at 4.7 million times our sun's light output.

The newfound super-bright star also takes on the mantle of perhaps being the second-most massive star in the galaxy, starting its life at more than 1,000 times the mass of our sun. That's because stellar mass and brightness rise in tandem.

"This is a fascinating object, it really is," said Eta Carina researcher Ted Gull of NASA's Goddard Space Flight Center.

Unlike stars the size of the sun and smaller, which are a dime a dozen, super-giant stars are very rare in the universe today. What's more, they live only a fraction as long as smaller stars -- just a billion years compared to six billion or more. These two limitations make the stellar heavyweights pretty hard to study, since there aren't many to choose from.

Since such stars are so hard to scout out through the dust here in our home galaxy, astronomers have resorted to scavenging through distant galaxies to find them. But the new discovery could change that.

"We really need to build up a population to understand what's going on," Gull told Discovery News.