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June 18: The Moon and the Sickle
Saturn rules the early-morning sky, shining at 1st magnitude in otherwise dim Pisces the Fish. One of the ringed planet’s many moons, Dione, passes due north of Saturn the morning of June 19. The 10th-magnitude moon’s progress is visible if you’ve got a dark sky and a telescope.
Two hours before sunrise, Saturn is nearly 20° high in the east. It’s easy to find as the brightest light in this part of the sky, skimming the border between southern Pisces and northern Cetus. Through a telescope, you’ll of course see Saturn’s stunning ring system, and should also easily pick up its largest and brightest moon, Titan, just northwest of the planet.
Dione — again, magnitude 10 — is much closer to the planet than Titan and lies northeast of Saturn. As the hours pass, it draws closer, passing due north of Saturn shortly before 4:30 A.M. PDT — note the time zone, as at this point the planet and moon will only be visible along the U.S. West Coast. The farther west you are, the better, as the sky is likely already growing light. See if you can identify Dione roughly an arcsecond above the planet’s north pole, despite the slowly brightening twilight; you might also try snapping a quick photo if you’ve got the setup, as that may show Dione’s position even if your eyes can’t find it.
Sunrise: 5:31 A.M.
Sunset: 8:32 P.M.
Moonrise: 10:41 A.M.
Moonset: —
Moon Phase: Waxing crescent (32%)
*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.
Alison Klesman is senior editor of Astronomy magazine. She holds a Ph.D. in astronomy and has studied a variety of topics, from minor planets to supermassive black holes.
