A serendipitous movie of an occultation of Io by its neighboring moon Europa when the team re-observed Io on the night of March 7, 2015 for a follow up to the work done for the published study. Europa happened to pass in front of Io as observed from Earth. Loki is the bright volcano on the left and Pele the other one on the lower right. Europa appears dark because the water ice on its surface absorbs the incident sunlight at the wavelength used.
The images were shot by LMIRcam, (The Large Binocular Telescope Mid-InfraRed Camera) which operates in the near-infrared band at 3 to 5 micrometres.
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| A raw LMIRcam image of Io showing the fringes on Loki Patera (bright spot) and on fainter active volcanic areas |
You can see several volcanic features on the surface of Io on the LBT image, including the massive Loki Patera region, which is represented as a bright patch. This lava lake is about 200 km across. The four Galilean moons of Jupiter (Io, Europa, Callisto and Ganymede) range in diameter from Europa at 3,121 km to Ganymede at 5,262 km, and yet only appear as star-like points of light less than 1.7” to 0.8” in size as seen from Earth.
