Astronomers have discovered that a massive star known as the Peony Nebula star ranks as the second-brightest in our Milky Way galaxy. The astronomers estimate that the star shines 3.2 million times as brightly as our sun, which is enough to get it a galactic silver medal; the brightest star ever detected is Eta Carinae, which is 4.7 million times brighter than our own little star.

The Peony nebula star… doesn’t look all that bright to the naked eye. Sirius is still the undisputed local champion, based on what we can see in the night sky. But a big factor behind Sirius’ apparent brightness is its relative proximity to Earth – a mere 8.7 light-years, or roughly 50 trillion miles [MSNBC]. In contrast, the Peony Nebula star lies about 26,000 light-years away, in the dusty heart of the Milky Way. In their upcoming report in the journal Astronomy & Astrophysics, researchers say the Spitzer telescope could reveal many other super-bright stars in the same region.

Both the Peony Nebula star and its rival in brightness, Eta Carinae, are classified as giant blue stars that have a relatively short lifespan, and which explode into spectacular supernovae. Astronomers say that watching these stars could give them fascinating clues about the cosmic cycle of star death and rebirth. “For all we know, they may have already blown themselves up and we’re just waiting for the light to get to us to tell us that,” [said researcher Michelle Thaller]…. “These are real drivers of a galaxy’s life cycle,” Thaller says. “When these things go off, they will probably kick off a new generation of stars” [New Scientist].

Researchers used NASA‘s space-based Spitzer telescope to probe the dust cloud’s mysteries: Infrared light emitted by the stars cuts through the gas and dust and allows astronomers to detect stars shrouded in the interstellar mists [Discovery News]. Researchers had already known of the star’s existence, named for the flowery shape of its surrounding cloud of gas and dust. But the blanket of dust at the galaxy’s center had obscured the star’s true brilliance [Science News].

For images of a blue giant in full supernova action, check out the DISCOVER article, “One Spectacular Stellar Death.”

Image: NASA/JPL-Caltech/Potsdam Univ.

July 16th, 2008 1:13 PM Tags: Milky Way, NASA, stars, supernova, telescopes
by Eliza Strickland in Space | 2 comments | RSS feed | Trackback >