New Horizons Spots Pluto's Faintest Known Moons

Explanation: For the first time, NASA's New Horizons spacecraft has photographed Kerberos and Styx - the smallest and faintest of Pluto's five known moons. Following the spacecraft's detection of Pluto's giant moon Charon in July 2013, and Pluto's smaller moons Hydra and Nix in July 2014 and January 2015, respectively, New Horizons is now within sight of all the known members of the Pluto system. The images detecting Kerberos and Styx shown here were taken with New Horizons' most sensitive camera, the Long Range Reconnaissance Imager (LORRI), from April 25-May 1. Each observation consists of five 10-second exposures that have been added together to make the image in the left panel, and extensively processed to reduce the bright glare of Pluto and Charon and largely remove the dense field of background stars (center and right panels), in order to reveal the faint satellites, whose positions and orbits, along with those of the brighter moons Nix and Hydra, are given in the right panel.


Image credit: NASA/JHUAPL/SwRI.