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A Celestial Shamrock
Sh2-205, LBN 148.11-0.45; CY Camelopardalis, HD 24094, HIP 18151
Description: Nebula > Emission > HII Region; Star>Variable>Spectral Type B
Position (J2000): RA 03h 52.8m; Dec +53° 29.0'
Distance: About 3,000 light years
Size: 45 light-years
Field of View: 1.72 x 1.72 degrees
Orientation: North is directly up
Image Credit: NASA/JPL-Caltech/WISE Team
Release Date: March 17, 2011
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ABOUT THIS IMAGE:
Many consider the shamrock to be a symbol of rebirth and life, making it a fitting symbol for St. Patrick's Day, which happens to occur around the same time as the Spring Equinox in the Northern Hemisphere. It is also fitting that today's image from NASA's Wide-field Infrared Survey Explorer, or WISE, features a region of star birth wrapped in a blanket of dust, colored green in this infrared view. Designated as Sh2-205, this interstellar cloud of dust and gas is a classic example of what astronomers call an HII region, because of all the ionized hydrogen, or HII, within it. Ionized gases carry an electric charge.
stellar nursery is made up of a shell of ionized gas surrounding a void
with one or more extremely hot, bright stars in the middle. The strong
stellar winds and intense ultraviolet radiation both clear away nearby
gas and dust and heat the remaining dust in the shell, causing it to glow
in the infrared wavelengths that WISE detected. It's possible that the
bright central star inside the red dust -- called CY Camelopardalis -
is the main culprit; however other nearby stars may be involved as well.
The dust in the surrounding shell, colored green in this image, is mostly
made of polycyclic aromatic hydrocarbon grains, similar to soot. They
are warmer in temperature than the more metallic dust grains seen glowing
in red around CY Cam. The heavy elements in such dust particles are cooked
up in previous generations of stars and then incorporated into the new
stars that are born from the cloud. This really is a region of rebirth
Scattered throughout the region you can see small clusters of bright red objects, especially near the upper left portion of the image. These are likely "Young Stellar Objects," surrounded by cocoons of dense dust. Young Stellar Objects are stars in their earliest stages of life, just coming together and beginning to start their nuclear fusion. The clouds of gas and dust surrounding each star provide the material from which future planets might possibly form. Perhaps we are seeing the birth of several new planetary systems in this one image alone.
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