Abstract The August, 1989 Voyager encounter with the Neptune system provided the fundamental information required to understand the volatile budget and transport processes on Neptune's large moon Triton. The discovery of nitrogen in Triton's atmosphere at a surface pressure of roughly 15–20 microbars, and surface temperature of 35–40K, combined with earlier ground-based spectra. strongly indicate that the atmosphere is supported by extensive deposits of surface nitrogen frosts, which are moved seasonally through the atmosphere in response to varying insolation. Likewise, Voyager and ground-based data support the notion that methane frost exists on the surface and is resupplying the atmosphere. The simplest model of global volatile transport, in which the albedo of the frost is constant, illustrates heuristically some interesting aspects of this system but does not reproduce the frost distribution seen by Voyager. Instead, models in which the nitrogen deposits have variable albedo, caused by grain size changes or contaminants, must be invoked. The grain growth properties and thermodynamics of pure nitrogen may also determine the radiating properties of the nitrogen frosts, which must be accounted for in the transport models. Finally, simple sublimation of nitrogen from the lit pole is not the only means of transport through the atmosphere: the detection of plumes above the surface may indicate the operation of moist convective processes which affect the transfer of both mass and energy from summer to winter regions.
Volatile processes in Triton's atmosphere and surface
Advances in Space Research ; 12 , 11 ; 97-111
1992-01-01
15 pages
Article (Journal)
Electronic Resource
English
Volatile processes in Triton's atmosphere and surface
NTRS | 1992
|A model of Triton's atmosphere and ionosphere
Elsevier | 1992
|Triton's eruptions analogous to comet Halley's?
Elsevier | 1992
|Triton's first flight for US Navy
British Library Online Contents | 2013