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April 15: Spot the Moon and Mercury this morning
Our attention is back on Jupiter in the west this evening, though, as Ganymede finally reaches the planet’s eastern limb and begins a transit overnight. First, though, Io is completing another transit as darkness falls across the East Coast, slipping away from the western limb shortly after 8:10 P.M. EDT. Its shadow is still transiting the disk, visible as the sky above the Midwest starts to darken. Io’s shadow leaves the disk just before 9:30 P.M. EDT, and now your attention can turn east of Jupiter, where Ganymede is approaching the limb.
The large moon finally starts a transit at 12:53 A.M. EDT (now the 17th in the Eastern time zone, but late on the 16th for the rest of the U.S.). It takes more than three hours to make the trip; only Pacific Coast observers will see the transit end, around 1:10 A.M. PDT on the 17th. However, even those observers won’t see the shadow transit, as it begins after the planet sets for the contiguous U.S.
Sunrise: 6:20 A.M.
Sunset: 7:40 P.M.
Moonrise: 5:38 A.M.
Moonset: 7:07 P.M.
Moon Phase: New
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40° N 90° W. The Moon’s illumination is given at 10 P.M. local time from the same location.
