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May 17: Glimpse the zodiacal light
The Moon is now just over two days old, a sliver of its eastern limb lit by the Sun as sunrise slowly crawls across the nearside. Catch the delicate crescent this evening, when it stands just 2° from Venus in the darkening sky after sunset. The pair is visible for more than 2½ hours after sunset, slowly sinking to disappear below the horizon shortly before 11 P.M. local daylight time. That means you have plenty of time to get out and enjoy them.
Venus is a blazing magnitude –3.9, the brightest point of light in the sky. It’s located in far northeastern Taurus — but it will move into western Gemini, near the Twins’ feet, by tomorrow evening. It joins bright Jupiter, which is closer to the heads of the Twins, shining at magnitude –1.9.
Check out Venus through a telescope and you’ll see a lovely 12”-wide disk that appears 83 percent lit. The best time to view it is before the sky gets too dark, as Venus is so bright that the bright sky around it actually aids in viewing it. After dark is the time to check out Jupiter, which stretches 34” wide and sports four bright moons visible around it: Europa (closer) and Callisto to the east, and Io (closer) and Ganymede to the west. At least, that’s the moons’ orientation early in the evening — Ganymede is moving east, while Io is moving west. Around 11:20 P.M. EDT, these two moons stand in a north-south line; after this, they swap places, with Ganymede closer to Jupiter’s western limb than Io.
The Moon passes 3° north of Venus at 10 P.M. EDT and stands between Venus and Jupiter tomorrow evening, so make sure to come back and enjoy the view then (and keep reading).
Sunrise: 5:42 A.M.
Sunset: 8:11 P.M.
Moonrise: 6:50 A.M.
Moonset: 11:04 P.M.
Moon Phase: Waxing crescent (8%)
*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.
