Saturn is the second-largest planet in our solar system, after Jupiter. It hosts an extensive atmosphere composed primarily of Hydrogen and Helium.

My research on Saturn investigates the upper regions of its atmosphere, it's thermosphere and ionosphere, where neutral particles and ions occur simultaneously. This is the region where the atmosphere of Saturn interacts with interplanetary space and the solar wind. Solar EUV radiation is absorbed in Saturn's thermosphere, partly ionizing its gases and heating the dayside. Since Saturn is located around 9.5 times as far away from the Sun as Earth, solar heating there is significantly weaker, and other processes heating the atmosphere are at least equally important as solar radiation.

The presence of a magnetic field on Saturn protects its atmosphere from direct exposure to the solar wind, but the atmosphere is affected by electric fields and high energetic particles which originate from the interaction of Saturn's magnetosphere with the solar wind. The electric fields map into the high latitude regions, near Saturn's poles, and generate strong frictional ("Joule-") heating. The incident charged particles generate spectacular auoral emissions, comparable to those found on Earth, which allow us to remotely sense the atmospheric gases, temperatures and processes.

In close collaboration with colleagues at Boston University and University College London I developed a General Circulation Model (GCM) for Saturn's thermosphere and ionosphere. This model has led to important discoveries about the processes driving the winds in Saturn's upper atmosphere. It is being used for predictions and comparisons with ground-based observations, as well as those currently carried out by the Cassini spacecraft, in orbit around Saturn since July 2004.

For more information about my work, please see the Publication List or contact me.

Temperatures and winds in Saturn’s Thermosphere, as modeled by the Saturn General Circulation Model

Global profile of electron densities near the altitude of peak density in Saturn’s ionosphere, as modeled by the Saturn General Circulation Model.

Image credit: NASA/JPL/Space Science Institute