June 18, 2010
Image of the Day: Red Monster of the Milky Way
Yet another amazing cosmic object: The Wolf-Rayet star framed like a viper's eye inside the red ring, about 16,000 light-years from Earth, is one of the most massive stellar objects of the Milky Way galaxy.
The star, named V385 Carinae, is 35 times as massive as our sun, with a diameter nearly 18 times as large, and shines with more than one million times the amount of light.
The material is puffed out into clouds like the one that glows brightly in this WISE image. In this case, the hollow sphere showed up prominently only at the longest of four infrared wavelengths detected by WISE. Astronomers speculate this infrared light comes from oxygen atoms, which have been stripped of some of their electrons by ultraviolet radiation from the star. When the electrons join up again with the oxygen atoms, light is produced that WISE can detect with its 22-micron infrared light detector. The process is similar to what happens in fluorescent light bulbs.
Infrared light detected by WISE at 12 microns is colored green, while 3.4- and 4.6-micron light is blue. The green, kelp-looking material is warm dust, and the blue dots are stars in our Milky Way galaxy.This image mosaic is made up of about 300 overlapping frames, taken as WISE continues its survey of the entire sky -- an expansive search, sure to turn up more fascinating creatures swimming in our cosmic ocean.