The location of active geyser-like eruptions and related features close to the current subsolar latitude on Triton suggests a solar energy source for these phenomena. Solidstate greenhouse calculations have shown that sunlight can generate substantially elevated subsurface temperatures. A variety of models for the storage of solar energy in a sub-greenhouse layer and for the supply of gas and energy to a geyser are examined. "Leaky greenhouse" models with only vertical gas transport are inconsistent with the observed upper limit on geyser radius of ∼ 1.5 kilometers. However, lateral transport of energy by gas flow in a porous N2 layer with a block size on the order of a meter can supply the required amount of gas to a source region ∼1 kilometer in radius. The decline of gas output to steady state may occur over a period comparable with the inferred active geyser lifetime of five Earth years. The required subsurface permeability may be maintained by thermal fracturing of the residual N2 polar cap. A lower limit on geyser source radius of ∼50 to 100 meters predicted by a theory of negatively buoyant jets is not readily attained.
|Publication Subtype||Journal Article|
|Title||Subsurface energy storage and transport for solar-powered geysers on Triton|
|Publisher||American Association for the Advancement of Science (AAAS)|
|Contributing office(s)||Astrogeology Science Center|
|Google Analytic Metrics||Metrics page|