A Cosmic Wreath: Barnard 3 in Perseus | NASA WISE Mission
NASA's Wide-field Infrared Survey Explorer (WISE) Mission presents the "Wreath Nebula." Although this is not the nebula's official name (it is actually called Barnard 3, or IRAS Ring G159.6-18.5), one might picture a wreath in these bright green and red dust clouds—a ring of evergreens donned with a festive red bow, a jaunty sprig of holly, and silver bells throughout. Interstellar clouds like these are stellar nurseries, places where baby stars are being born.
Wreaths are part of many ancient traditions dating back to the earliest civilizations. The circle is a symbol of immortality; throughout history, wreaths have been associated with life, rejuvenation, and renewal. Originally, wreaths were worn around the head, neck, or waist.
The Greeks awarded laurel wreaths to their triumphant athletes; in the Persian Empire, they were worn on the head as a symbol of importance; and ancient Romans wore them like crowns. In Sweden, candles were incorporated into the wreaths to celebrate the return of light after the winter solstice. Nowadays, we use them in a window or on a door as a sign of welcome during the holidays.
In this NASA WISE infrared image, the green ring (evergreen) is made of tiny particles of warm dust whose composition is very similar to smog found here on Earth. The red cloud (bow) in the middle is probably made of dust that is more metallic and cooler than the surrounding regions. The bright star in the middle of the red cloud, called HD 278942, is so luminous that it is likely what is causing most of the surrounding ring to glow. In fact, its powerful stellar winds are what cleared out the surrounding warm dust and created the ring-shaped feature in the first place. The bright greenish-yellow region left of center (holly) is similar to the ring, though more dense. The bluish-white stars (silver bells) scattered throughout are stars located both in front of, and behind, the nebula.
Regions similar to this nebula are found near the band of the Milky Way galaxy in the night sky. The “wreath” is slightly off this band, near the boundary between the constellations of Perseus and Taurus, but at a relatively close distance of only about 1,000 light-years, the cloud is a still part of our Milky Way.
The colors used in this image 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.
NASA's Jet Propulsion Laboratory, Pasadena, Calif., managed and operated the Wide-field Infrared Survey Explorer for NASA's Science Mission Directorate, Washington. The principal investigator was Edward Wright at UCLA.
https://www.jpl.nasa.gov/missions/wide-field-infrared-survey-explorer-wise/
Release Date: Dec. 22, 2011
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