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May 20: The Moon checks in on the Beehive
Saturn now dominates the predawn sky and Mars is growing easier to view as it rises slightly earlier each day. Neptune, the most distant planet in the solar system, is also visible before sunrise, although it remains relatively low while the sky is still dark and doesn’t rise out of the horizon haze until closer to sunrise.
By 4:30 A.M. local daylight time, 1st-magnitude Saturn is 10° high in the eastern sky. It’s the brightest point of light here, outshining any of the stars around it. Magnitude 1.3 Mars is just a tad fainter, but it’s also still very close to the horizon, only about 1.5° high and located to Saturn’s lower left. Try to follow it as the sky brightens — it will rise higher the closer you get to sunrise, but the twilight will begin to wash it out as well. You can opt to view it through a telescope, but make sure to put away your optics at least several minutes before sunrise from your location, which may differ from the time we give below.
Saturn is a better telescopic object — its rings are clearly visible, and you might even glimpse its brightest moon, Titan, far west of the planet in a dark sky before twilight begins. Saturn’s disk is 16” wide, framed by rings stretching about 37” from end to end. Compare this to tiny Mars if you can catch it, whose disk is just 4” across.
Sunrise: 5:40 A.M.
Sunset: 8:14 P.M.
Moonrise: 10:32 A.M.
Moonset: 12:43 A.M.
Moon Phase: Waxing crescent (36%)
*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.
