Io: Volcanic thermal sources and global heat flow

摘要: Abstract We have examined thermal emission from 240 active or recently-active volcanic features on Io and quantified the magnitude distribution of their heat flow during Galileo epoch. use spacecraft data a geological map to derive an estimate maximum possible contribution small dark areas not detected as thermally but which nevertheless appear be sites recent activity. utilize trend analysis extrapolate smallest detectable sources these mapped areas. Including additional estimates for “outburst” eruptions multitude very (“myriad”) hot spots, we account ∼62 × 10 12  W (∼59 ± 7% Io’s total emission). Loki Patera contributes, average, 9.6 × 10 (∼9.1 ± 1%). All paterae contribute 45.3 × 10 (∼43 ± 5%). Although fields cover much larger area than paterae, they only 5.6 × 10 (∼5.3 ± 0.6%). Bright ∼2.6 × 10 (∼2.5 ± 0.3%). Outburst eruption phases spots no more ∼4% emission: this is probably value. About 50% emanates 1.2% surface. Of flow, 41 ± 7.0% remains unaccounted in terms identified sources. Globally, uniformly distributed. Power output per unit surface slightly biased towards mid-latitudes, although there stronger bias toward northern hemisphere when included. There slight favoring outbursts where locations were well constrained. find peaks at ∼315°W ∼105°W (using 30° bins). minimum around 200°W (almost anti-jovian longitude) significant regional difference. These troughs suggest shift east predicted global patterns resulting tidal heating asthenosphere. Global dominated by especially (312°W, 12°N). Thermal flows maximises between 165°W 225°W. Finally, it that smaller present angular resolution detection limits, and/or cooler, secondary processes involving sulphurous compounds, may responsible least part associated with known Such activity should sought out next mission Io.