Jupiter's Moons Io and Europa Cross Paths in Celestial Event Visible Across U.S.
On April 13, 2026, a notable celestial event involving Jupiter's moons Io and Europa is observable across the United States. Shortly after midnight Central Daylight Time, Io stands just a few arcseconds north of Europa, while Europa's shadow transits Jupiter's disk. This event is part of a series of movements by the Galilean moons, showcasing the orbital mechanics of the solar system's largest planet. As twilight fades, Europa begins its transit across Jupiter, visible from the middle of the U.S. Io, moving eastward, crosses paths with Europa, and later disappears behind Jupiter in an occultation. This event is visible for the western two-thirds of the U.S., providing a unique opportunity for sky watchers to observe the dynamic interactions of Jupiter's moons. 
