Night Falls on Pluto's Big Moon Charon (Photo)

Pluto's largest moon, Charon, is cloaked in darkness, with just a tiny sliver lit up by the distant sun, in a newly released photo. NASA's New Horizons spacecraft captured the image on July 17, 2015, three days after the probe's historic flyby of Pluto. "Charon's nighttime landscapes are still faintly visible by light softly reflected off Pluto, just as 'Earthshine' lights up a new moon each month," agency officials wrote in a description of the image, which was released Friday (Jan. 22).