Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2004 April 14
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Massive Star Forming Region DR21 in Infrared
Credit: A. Marston (ESTEC/ESA) et al., JPL, Caltech, NASA

Explanation: Deep in the normally hidden recesses of giant molecular cloud DR21, a stellar nursery has been found creating some of the most massive stars yet recorded. The orbiting Spitzer Space Telescope's Infrared Array Camera opened the window into the cloud last year in mid- infrared light. The cloud is opaque to visible light because of dense interstellar dust. Noticeable in the above representative color infrared Spitzer image are huge bubbles, a complex tapestry of dust and gas, and very massive stars. The infrared filaments actually glow because of organic compounds known as PAHs. The intricate patterns are caused by complex interactions between interstellar winds, radiation pressures, magnetic fields, and gravity. The pictured region spans about 75 light years and lies about 6,000 light years distant toward the constellation of Cygnus.

Tomorrow's picture: Venus and the Pleiades

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