Ruach Planitia is a roughly circular flat plain and probable cryolava lake on Neptune's moon Triton. It is located in Triton's northern hemisphere within Monad Regio and directly borders the cryovolcanic plains of Cipango Planum. Ruach Planitia, along with the other walled plains on Triton, is one of the youngest and flattest features on Triton.
Voyager 2 image of Ruach Planitia. The crater Amarum is located to the lower right, and Dilolo Patera occupies much of Ruach Planitia's center. Parts of Tuonela Planitia can be seen at left
A cryovolcano is a type of volcano that erupts gases and volatile material such as liquid water, ammonia, and hydrocarbons. The erupted material is collectively referred to as cryolava; it originates from a reservoir of subsurface cryomagma. Cryovolcanic eruptions can take many forms, such as fissure and curtain eruptions, effusive cryolava flows, and large-scale resurfacing, and can vary greatly in output volumes. Immediately after an eruption, cryolava quickly freezes, constructing geological features and altering the surface.
Diagram of Enceladus's south polar plumes, an example of explosive cryovolcanism, and Enceladus's internal ocean
Enceladus's south polar plumes
Edifice of Wright Mons, a likely cryovolcano on Pluto. Coleman Mons can be seen just southwest of Wright Mons
Ruach Planitia and Tuonela Planitia, Triton
