The Peony nebula (reddish cloud around white circle) near the galactic centre is home to a star that rivals the stellar powerhouse Eta Carinae in brightness(Image: NASA/JPL-Caltech/Potsdam Univ)
The star had been discovered previously in the Peony nebula near the galaxy's dusty centre is Milky Way's brightest star. But infrared observations taken from the ground and with NASA's Spitzer Space Telescope have pierced the dust to reveal just how bright the star is.
It boasts a wattage of about 3.2 million Suns. That is close to the output of Eta Carinae, the current record holder, which shines with the light of about 4.7 million Suns. However, measuring stellar brightness is not an exact science, and the stars may actually radiate similar amounts of light.
It's possible that the galaxy's brightest star has not even been discovered yet. Both Eta Carinae and the Peony nebula star are evolved blue giants known as "Wolf-Rayet" stars, which have masses of 100 to 200 Suns.The Peony nebula star lies about 26,000 light years away and Eta Carinae about 7500 light years away.
Journal reference: Astronomy & Astrophysics (forthcoming)
http://space.newscientist.com/article/dn14328-whos-the-brightest-star-of-all.html
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