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Butterfly Nebula, W40
Infrared image from NASA's Spitzer Space Telescope showing W40, a nebula that resembles a butterfly. W40 (short for Westerhout 40) is a cloud of gas and dust in space where new stars may be forming. The butterfly's two 'wings' are giant bubbles of hot, interstellar gas blowing from the hottest, most massive stars in this region. The material that forms W40's wings was ejected from a dense cluster of stars that lies between the wings in the image. The hottest, most massive of these stars, W40 IRS 1a, lies near the center of the star cluster. W40 lies about 1,400 light-years from the Sun. This image is composed of four images taken with the Spitzer telescope's Infrared Array Camera (IRAC) in different wavelengths of infrared light: , , and m (shown as blue, green, orange and red). Organic molecules made of carbon and hydrogen, called polycyclic aromatic hydrocarbons (PAHs), are excited by interstellar radiation and become luminescent at wavelengths near microns, giving the nebula its reddish features. Stars are brighter at the shorter wavelengths, giving them a blue tint. Some of the youngest stars are surrounded by dusty disks of material, which glow with a yellow or red hue.
Size: 4600px × 3000px
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Photo credit: © Science History Images / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: 1a, 40, astronomic, astronomical, astronomy, butterfly, evolution, galactic, galaxies, galaxy, gas, interstellar, irs, nebula, nebulae, nebular, nebulas, space, spitzer, star, stellar, telescope, universe, w40, westerhout