|Date of discovery||June 26, 2012|
|Name of discoverer||M. R. Showalter|
|Name origin||River of the underworld, and object of an oath binding even on the gods.|
|Order from primary||2|
|Semi-major axis||42,656 km|
|Sidereal month||20.16155 da|
|Inclination||0.809° to Pluto's equator|
Styx is the second presently known moon of Pluto. M. R. Showalter of the New Horizons Imaging Team discovered it in 2012. They were searching carefully for any stray object with which their robot rocket probe New Horizons might collide in its passage through the Plutonian system.