Special Date :Wednesday March 7 2007.

The Io Plasma Torus: Volcanoes, Atmospheres, and Magnetospheres, Oh My!

12:00- 1:00 pm , 102 VanderWerf

Jeff Morgenthaler, Ph.D.

University of Washington

Io is the the innermost of the four Galilean satellites.Because of the gravitational effects of the other three satellites on its orbit and its proximity to Jupiter, Io is subject to considerable tidal heating.  As a result, Io is the most volcanic body in the solar system.  These volcanoes provide material for a tenuous atmosphere composed primarily of sulfur dioxide.  Material in this atmosphere that happens to become ionized is swept away by Jupiter's powerful and rapidly rotating magnetic field, forming a donut-shaped structure called the Io Plasma Torus (IPT).  The IPT can be imaged in one of several ion emission lines using narrow-band filters and modest-aperture telescopes, such as the Harry F. Frissel Observatory at Hope College .  Frequent monitoring of the IPT will help constrain properties of Jupiter's magnetic field and the solar wind environment in which it is embedded. Time allowing, I will also discuss how similar narrow-band imaging techniques could be used to study comets with the Hope College observatory and show how the relatively recent discovery of X-rays from comets has renewed the interest of the scientific community in my Ph.D. thesis data.