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February 24: Chase the Coma galaxy cluster
Already high in the east as darkness falls, Jupiter still dominates the constellation Gemini. The gas giant’s large moon Ganymede transits the disk this evening, with its shadow following a few hours later. You’ll be able to catch the event through a telescope.
Ganymede’s transit begins at 8:55 P.M. EST, with the moon moving in front of the disk from the east. Also east of the planet are the three other Galilean moons (in order of distance): Io, Europa, and Callisto.
Ganymede moves east to west across Jupiter, reaching halfway around 10:30 P.M. EST. It slips away from the southwestern limb around 12:10 A.M. EST on the 26th (in Eastern time only), with its shadow still yet to appear. That shadow finally makes its way onto the cloud tops near the southeastern limb around midnight CST, four hours after Ganymede’s transit began and with Ganymede now well away from the southwestern limb. The shadow takes more than three hours to transit, disappearing around 2:20 A.M. MST, with Jupiter getting quite low in the Midwest.
Sunrise: 6:39 A.M.
Sunset: 5:48 P.M.
Moonrise: 11:19 A.M.
Moonset: 2:29 A.M.
Moon Phase: Waxing gibbous (69%)
*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.
