February 5, 2013
Smog Detected At Northern Hemisphere Of Saturn Moon Titan
April Flowers for redOrbit.com - Your Universe Online
An international group of scientists, led by Panayotis Lavvas of the University of Reims, Champagne-Ardenne, used data from NASA's Cassini mission to describe, in unparalleled detail, how aerosols in the highest part of the atmosphere are kick-started on Saturn's moon Titan.The study, published in a recent issue of Proceedings of the National Academy of Sciences (PNAS), seeks to understand aerosol formation at Titan because it could help predict the behavior of smoggy aerosol layers on Earth.
According to the research team, the reddish-brown smog that is Titan's trademark appears to begin with solar radiation on molecules of nitrogen and methane in the ionosphere. This creates a soup of negative and positive ions. Organic molecules and the ions collide, growing into larger and more complex aerosols. These aerosols bump into each other lower in the atmosphere, where they coagulate and simultaneously interact with other neutral particles. The heart of the physical processes that rain hydrocarbons on Titan's surface forms from these particles, creating lakes, channels and dunes.
Three Cassini instruments — the plasma spectrometer, the ion and neutral mass spectrometer, and the radio and plasma wave science experiment — provided the data analyzed for the new study.