Fig. 2. Detail of the site of the putative cryovolcanic emission of NH₃-bearing H₂O in the main trough of Virgil Fossae.

(A) Section of Virgil Fossae from the Pluto base map. Arrows point to topographic features that are muted in form by an apparent mantling by material ejected in a cryovolcanic event within the fossa main channel. (B) Same region shown with the H₂O ice distribution (17, 18) in blue overlain on the base map: Darker shade of blue indicates greater concentration based on the strength of the ice absorption bands. Image credit: NASA, Johns Hopkins University, Southwest Research Institute.