Triple Transit and Mutual Events

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Triple Transit and Mutual Events

Image Credit and Copyright: Christopher Go

Explanation: These panels show Jupiter, the ruling gas giant of the Solar System, as seen from Cebu City in the Philippines, Earth. The well-timed Telescopic Views detail remarkable Jupiter's Galilean Moons transits and mutual events. The top panel shows Io disappearing into Jupiter’s shadow to the right. However, the three large Jovian moons are visible against Jupiter's banded disc. The brighter Europa and the darker Ganymede, which also cast their shadows on Jupiter's cloud tops, are to the left. Callisto, located below the planet's edge and just near its edge, is Callisto. These three moons are in a triple transit across Jupiter's face. The shadows of Europa, Ganymede and Callisto are visible in the middle panel. However, Ganymede has passed or occulted in front Europa. The bottom panel shows a rare view of Jovian Moons in Eclipse while transiting Jupiter. Ganymede's shadow falls on Europa. Similar events when Galilean moons occult or eclipse one another can be observed from Earth's perspective every six years, or so, when Jupiter is close to its own equinox.