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April 3: Mercury stands far west of the Sun
Europa, now having reached the far western end of its orbit and heading back toward the planet, disappears in an occultation behind the disk of Jupiter at 11:30 P.M. EDT.
If you can, get your telescope on the planet at least 40 minutes before that — shortly before 11 P.M. EDT, Callisto stands due south of Ganymede, both far to Jupiter’s west. Closer to the planet is Io, while Europa is even closer, closing in on the western limb. After this, Callisto and Ganymede pull apart, with Callisto moving away from the planet and Ganymede toward it. That’s because Callisto’s orbit is wider than Ganymede’s, so the former has not yet reached its greatest western extent.
Meanwhile, Europa takes some three hours to cross behind Jupiter but emerges into the planet’s shadow, staying invisible even once it has moved past the limb. Only observers in the western half of the U.S. will be able to catch its eventual reappearance, some 35” east of the eastern limb around 2 A.M. PDT on April 5.
Sunrise: 6:39 A.M.
Sunset: 7:28 P.M.
Moonrise: 10:32 P.M.
Moonset: 7:31 A.M.
Moon Phase: Waning gibbous (91%)
*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.
