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Updated: Jun 29, 2026
07:49
On-line Analysis of Nitrogen Containing Compounds in Complex Hydrocarbon Matrixes
Published on: August 5, 2016
Evolution of a nitrogen atmosphere on titan
Science (New York, N.Y.)
|August 18, 1978
Summary
Titan
Area of Science:
- Planetary Science
- Astrochemistry
- Atmospheric Science
Background:
- Titan's atmosphere composition is not fully understood.
- Previous models did not fully explain Titan's atmospheric conditions.
Purpose of the Study:
- To investigate the atmospheric evolution of Titan.
- To explain the current atmospheric composition and surface temperature of Titan.
Main Methods:
- Photochemical calculations were performed.
- Gas-phase reaction pathways were analyzed.
- Atmospheric temperature and pressure conditions were modeled.
Main Results:
- Ammonia (NH3) outgassing on Titan likely converted to a dense nitrogen (N2) atmosphere.
- A methane-hydrogen (CH4-H2) greenhouse effect may have raised temperatures to 150 K.
- Approximately 20 bars of N2 could have evolved, explaining the 200 K surface temperature.
- Unlike Jupiter, ammonia is not recycled in Titan's atmosphere.
Conclusions:
- The proposed N2 formation pathway explains Titan's atmospheric density and surface temperature.
- The lack of ammonia recycling explains the failure to detect NH3 in Titan's upper atmosphere.
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