This is the Griffith Observatory Sky Report through May 27, 2015. Here’s what’s happening in the skies of southern California.
The waxing moon moves from low in the west to high in the south at sunset between the 20th and 25th. Between these dates, its phase changes from crescent to first quarter, then is waxing gibbous through the 27th. Over the same period, moonset moves from 10:25 p.m. to 2:13 a.m.
The brightest planet, Venus, and the second brightest planet, Jupiter, are moving closer to each other in the early evening sky. At sunset, Venus appears about 40 degrees above the west-northwest horizon while Jupiter is higher and to the upper left of Venus. Between the 20th and 27th, the apparent separation between the two planets will shrink from 30 degrees to 25 degrees. Venus can be seen until it slips below the horizon at 11:20 p.m. Jupiter sets at about 1:00 a.m. The moon appears to the lower left of Venus on the 21st and to the lower left of Jupiter on the 23rd.
Through a telescope, Venus displays a 56-percent illuminated gibbous phase, and is 21 arcseconds across. Jupiter’s fully lit disk appears 35 arcseconds wide. The giant planet’s four largest moons can be seen through binoculars, while a telescope is needed to see the details of Jupiter’s cloudy atmosphere. Jupiter’s giant oval storm, the Great Red Spot, will be visible to observers in California on Friday the 22nd and Sunday the 24th.
Golden Saturn, in Libra the Scales, is at opposition – the point in the sky opposite to the sun – on Thursday night, the 22nd. Saturn is at its brightest and closest for the year, and is visible all night. It rises in the east-southeast at sunset, crosses the meridian in the south at 1:00 a.m., and sets in the west-southwest at sunrise. A telescope will reveal the planet’s glorious rings, which are brighter than usual for a few days around Saturn’s opposition.
Free views of the sun during the day and of the moon, planets, and other celestial objects at night are available to the public in clear weather through Griffith Observatory’s telescopes from Tuesday through Sunday before 9:30 p.m. Check our website for the schedule. The next public star party on the grounds of Griffith Observatory, hosted by the Los Angeles Astronomical Society, the Sidewalk Astronomers, and the Planetary Society, will take place on Saturday, May 30.
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From Griffith Observatory, I’m Anthony Cook and I can be reached at firstname.lastname@example.org.