Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published September 19, 1985 | public
Journal Article

Physical state of volatiles on the surface of Triton

Abstract

The most recent analyses of infrared spectrophotometric studies of Neptune's satellite Triton concluded that both condensed methane and nitrogen are present. It was also concluded that the most likely surface configuration is a liquid nitrogen (N_2) 'ocean' with dry areas of solid methane (CH_4), and perhaps some exposed fine-grained water frost (H_2O). However, this model runs into some difficulties, especially when requirements of phase equilibrium between the solid and liquid components are imposed. Because an understanding of the distribution and state of volatiles is crucial in interpreting secular changes in Triton's appearance due to seasonal effects, and in planning observing strategies for the Voyager–Neptune/Triton encounter, we assess here several possible configurations for these volatiles on Triton. We conclude that the simplest volatile configuration which best satisfies the constraints with the least number of ad hoc assumptions is N_2 and CH_4 both in solid forms, perhaps partly as a microscopic mixture, but more probably as a disequilibrium assemblage, non-uniformly distributed. Thermodynamic equilibrium is then limited by seasonal transport and the finite diffusion time of CH_4 in crystalline N_2. Although a nitrogen ocean cannot be excluded, it requires very restrictive assumptions.

Additional Information

© 1985 Nature Publishing Group. Received 26 March; accepted 8 July 1985. This work was supported by NASA grants NAGW-185 and NAGW-450 and NSF grant AST-8206173. Contribution no. 4236 from the Division of Geological and Planetary Sciences, California Institute of Technology.

Additional details

Created:
August 22, 2023
Modified:
October 26, 2023