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An infrared view from NASA's NEOWISE mission of the Oort cloud comet C/2006 W3 (Christensen). The spacecraft observed this comet on April 20th, 2010 as it traveled through the constellation Sagittarius. Comet Christensen was nearly 370 million miles (600 million kilometers) from Earth at the time. The image is half of a degree of the sky on each side. Infrared light with wavelengths of 3.4, 12 and 22 micron channels are mapped to blue, green, and red, respectively. The signal at these wavelengths is dominated primarily by the comet's dust thermal emission, giving it a golden hue. The WISE sp…
