Geissler P E, McEwen A S, Ip W, Belton M J, Johnson T V, Smyth W H, Ingersoll A P
Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85711, USA.
Science. 1999 Aug 6;285(5429):870-4. doi: 10.1126/science.285.5429.870.
The Galileo spacecraft has detected diffuse optical emissions from Io in high-resolution images acquired while the satellite was eclipsed by Jupiter. Three distinct components make up Io's visible emissions. Bright blue glows of more than 300 kilorayleighs emanate from volcanic plumes, probably due to electron impact on molecular sulfur dioxide. Weaker red emissions, possibly due to atomic oxygen, are seen along the limbs, brighter on the pole closest to the plasma torus. A faint green glow appears concentrated on the night side of Io, possibly produced by atomic sodium. Io's disk-averaged emission diminishes with time after entering eclipse, whereas the localized blue glows brighten instead.
伽利略号宇宙飞船在木卫一被木星遮挡期间获取的高分辨率图像中，探测到了木卫一的弥漫性光学辐射。木卫一的可见辐射由三个不同的成分组成。超过300千雷利的亮蓝色辉光来自火山羽流，这可能是由于电子撞击分子二氧化硫所致。沿着边缘可见较弱的红色辐射，可能是由原子氧引起的，在最靠近等离子体环面的极点处更亮。微弱的绿色辉光似乎集中在木卫一的夜侧，可能是由原子钠产生的。木卫一进入日食后，其盘面平均辐射随时间减弱，而局部蓝色辉光则变亮。
