MEpedia:WikiProject Geographical coordinates/globe:

The  parameter specifies the planet, dwarf planet, asteroid, or natural satellite upon which the coordinates reside. Apart from earth (the default), recognized values are: mercury, venus, moon, mars, phobos, deimos, ceres, vesta, ganymede, callisto, io, europa, mimas, enceladus, tethys, dione, rhea, titan, hyperion, iapetus, phoebe, miranda, ariel, umbriel, titania, oberon, triton, and pluto.

For globes other than Earth, coord does not assume a specific reference system (in contrast with Earth's WGS84). Since the template defaults to east longitude, the  direction must be specified for globes that measure longitude westward. At the present time, only limited mapping is available for Mars and the Moon and none for other extraterrestrial bodies. For celestial coordinates, use Sky instead.