January 1, 2014
The Wreath Nebula, an emission nebula in Perseus
Image Credit: NASA/JPL-Caltech/WISE Team
The Wreath Nebula (also known as Barnard 3 or IRAS Ring G159.6-18.5) is an emission nebula and H II region of about 22 light-years across (ring diameter), located only some 1,000 light-years away within our Milky Way galaxy in the Perseus Molecular Cloud complex, near the boundary with the constellation of Taurus.
The green ring (the wreath) is made of tiny particles of warm dust whose composition is very similar to smog found here on Earth. The red cloud in the center is most likely made of dust that is more metallic and cooler than the surrounding regions.
HD 278942, the bright star in the middle of the red cloud which is brighter and hotter than our Sun, is so luminous that it is the likely cause of the surrounding ring’s glow. In fact its powerful stellar winds carved out a gigantic cavity in the nebula, creating a bubble of about 25 light-years in diameter. The bright greenish-yellow region left of the center is similar to the rest of the green “wreath” material, only more dense.
Interstellar clouds like these are stellar nurseries, where baby stars are being born. In this star-forming nebula new stars are being born throughout the dusty region, while the bluish-white stars scattered throughout are located both in front of, and behind, the nebula.
This false-color image was taken with the Wide-field Infrared Survey Explorer (WISE). The colors represent specific wavelengths of infrared light. Blue and cyan (blue-green) represent light emitted at wavelengths of 3.4 and 4.6 microns, which is predominantly from stars. Green and red represent light from 12 and 22 microns, respectively, which is mostly emitted by dust. North is straight up.