NASA Presents a Jupiter-Io Montage

Taken back in 2007 during the Cassini flyby, this image shows Io and Jupiter together. NASA says: "The image of Jupiter is an infrared color composite taken by the spacecraft's near-infrared imaging spectrometer, the Linear Etalon Imaging Spectral Array. The infrared wavelengths used highlight variations in the altitude of the Jovian cloud tops, with blue denoting high-altitude clouds and hazes, and red indicating deeper clouds. The prominent bluish-white oval is the Great Red Spot. The observation was made at a solar phase angle of 75 degrees but has been projected onto a crescent to remove distortion caused by Jupiter's rotation during the scan. The image of Io is an approximately true-color composite taken by the panchromatic Long-Range Reconnaissance Imager with color information provided by the Multispectral Visible Imaging Camera. The image shows a major eruption in progress on Io's night side, at the northern volcano Tvashtar. Incandescent lava glows red beneath a volcanic plume, whose uppermost portions are illuminated by sunlight. The plume appears blue due to scattering of light by small particles within it."

Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Goddard Space Flight Center