S+ Implantation in Oxide Ices: Relevance to Europa

<p>The implantation of reactive charged species within low-temperature solids is relevant to astrochemistry and may lead to physico-chemical changes within the solid, such as the formation of new molecules which incorporate the projectile. We have performed the high-fluence (>10<sup>16</sup> ions cm<sup>–2</sup>) implantation of S<sup>+</sup> into CO, CO<sub>2</sub> and H<sub>2</sub>O ices at 20 and 70 K. Our results show that implantation into CO and CO<sub>2</sub> results in the formation of SO<sub>2</sub> at 20 K, although no evidence of SO<sub>2</sub> was observed at 70 K. Implantation into H<sub>2</sub>O yields H<sub>2</sub>SO<sub>4</sub> hydrates. These results are applicable to Europa; one of the Galilean moons of Jupiter.</p>

Ground-based observations of the [SII] 6731 Å emission lines of the Io plasma torus

The Io Plasma Torus (IPT) is a doughnut-shaped structure of charged particles, composed mainly of sulfur and oxygen ions. The main source of the IPT is the moon Io, the most volcanically active object in the Solar System. Io is the innermost of the Galilean moons of Jupiter, the main source of the magnetospheric plasma and responsible for injecting nearly 1 ton/s of ions into Jupiter's magnetosphere. In this work ground-based observations of the [SII] 6731 Å emission lines are observed, obtained at the MacMath-Pierce Solar Telescope. The results shown here were obtained in late 1997 and occurred shortly after a period of important eruptions observed by the Galileo mission (1996-2003). Several outbursts were observed and periods of intense volcanic activity are important to correlate with periods of brightness enhancements observed at the IPT. The time of response between an eruption and enhancement at IPT is still not well understood.