Over the course of one complete year, NASA's Wide-field Infrared Survey Explorer (WISE) mapped out the entire sky using infrared light. One group of found objects that continues to fascinate both the scientific and the general public is that of comets. Here, NASA has grouped together the 20 comets found by the WISE mission into what it is calling a family portrait.
"The fuzzy background in each picture is due to random fluctuations in infrared light, primarily from dust in our own solar system," NASA explained. "Stars cannot be seen because they were subtracted during the process of combining multiple WISE pictures to make this view centered on the moving comets."
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