Io's volcanism controls Jupiter's magnetospheric activity

January 28, 2013 in Astronomy & Space / Space Exploration
Io, the most volcanic body in the solar system, is seen in front of Jupiter's cloudy atmosphere in this image from NASA's Galileo spacecraft, now orbiting the giant planet. Credit: NASA

Jupiter's volcanic moon Io spews out volcanic gas, which reaches its atmosphere and becomes ionized, forming what is known as the Io plasma torus. This plasma torus can interact with Jupiter's magnetosphere, possibly affecting auroral activity there.

To help determine whether Io's affects Jupiter's magnetosphere, Yoneda et al. analyzed ground-based observations of Jupiter's sodium nebula, which provides an indication of Io's volcanic activity and plasma content in the Io plasma torus, along with satellite-based measurements of called HOM emission, which is a sign of Jupiter's auroral activity.

They observe that Jupiter's sodium nebula was enhanced in late May through early June 2007, indicating that Io's volcanic activity increased during that period. The researchers observe that shortly after this enhancement began, Jupiter's HOM emission intensity decreased.

As a result, the authors conclude that increased volcanic activity on Io lessens auroral activity in Jupiter's magnetosphere.

More information: Io's volcanism controls Jupiter's radio emissions, Geophysical Research Letters, doi: 10.1002/grl.50095, 2013

Provided by American Geophysical Union

"Io's volcanism controls Jupiter's magnetospheric activity" January 28, 2013