One of the main differences between the star star and the star planet mechanisms is that where RS CVn-type stars generally have activity levels many times higher than those found in even the most active single solar-like stars11, stars hosting Jupiter-like planets have activity levels comparable to average solar-like stars12.
In December 2000, when the Sun was at its most active, SOHO undertook solar wind studies in coordination with Ulysses, which was then flying high in solar orbit over the Sun's southern polar region, in order to construct three-dimensional maps.
Europa is one of the most active bodies in the solar system: about the size of Earth's moon, and at its warmest only about -260F (-160C), and covered in an icy shell that makes one of the most reflective objects in the neighborhood.
Despite its 1.2-billion-kilometer distance from the sun, Titan is one of the most active bodies in the solar system.
When it is at its most active, the so-called solar maximum, there are more sunspots present, and therefore more flares releasing powerful bursts of energy into space, as well as sprays of hot ionised gases, or plasma, that scientists call the solar wind.
Called active solar trackers, most of these systems are expensive, require precise calibration, and are designed only for massive arrays of solar panels.
Impressive, yes, but nothing like what an extraterrestrial volcano can do, to judge from recent research involving Jupiter's moon Io, which scientists consider to be the most active volcanic body in the solar system.
After that encounter, the craft could visit the comet Borrelly, one of the most active to regularly visit the inner solar system, in September 2001.
