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February 10: The Moon approaches Antares
Observers in the eastern half of the U.S. can catch the large blot of Ganymede’s shadow sliding across the cloud tops of Jupiter as darkness falls this evening. The shadow is already transiting at sunset in the Eastern and Central time zones, with Ganymede itself just west of Jupiter, having recently completed its own transit.
Ganymede’s shadow disappears just after 8:15 P.M. EST, but the jovian show isn’t over yet. East of Jupiter, Io is visible closest to the planet; Callisto is visible just to Io’s east, with Europa farther east of them both. Over the next few hours, as Ganymede moves farther west, away from Jupiter, the other three moons are also moving west, closer to the planet.
Io finally reaches the limb and begins a transit at 12:06 a.m. EST (the 12th in EST only), followed by its shadow roughly 50 minutes later. By 1:30 A.M. EST (now the 12th for the Eastern and Central time zones), both are readily visible in front of the planet, moving from east to west. Io ends its transit just before 2:25 A.M. EST, with its shadow continuing until about 3:10 A.M. EST.
Sunrise: 6:58 A.M.
Sunset: 5:32 P.M.
Moonrise: 3:01 A.M.
Moonset: 11:48 A.M.
Moon Phase: Waning crescent (26%)
*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.
