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This is the Griffith Observatory Sky Report through June 21, 2017. Here’s what’s happening in the skies of southern California.
Summer begins in earth’s northern hemisphere on Tuesday, June 20 at 9:24 p.m. That moment, the summer solstice, is when the sun reaches its farthest point north of the celestial equator. The solstice also marks the start of winter in the southern hemisphere.
Griffith Observatory will celebrate the solstice with two free public presentations on the 20th. The first, at the Gottlieb Meridian Arc and Transit Corridor, starts at 12:55 p.m. and marks the local noon and the year’s highest meridian crossing of the sun. The second presentation, to observe the northernmost sunset of the year, will start at 7:50 p.m. at the engraved sunset lines on the Observatory’s west walkway. At both events, Observatory staff members will explain the astronomical workings of the seasons.
The planet Jupiter, in the constellation Virgo the Maiden, is the brightest object in the evening sky. It is high in the southwest when darkness falls, and sets in the west at about 2:00 a.m. Jupiter’s four largest moons can be spotted through binoculars, and Jupiter’s cloud belts and storms are interesting to observe through more powerful telescopes. The planet’s famous oval storm, the Great Red Spot, can be seen by observers on the West Coast at 9:00 p.m. on June 15th, 17th, and 20th.
The planet Saturn, in the constellation Ophiuchus the Serpent Bearer, is fainter than Jupiter but is the brightest object present in the southeast direction when night falls. Saturn is at opposition, meaning that it is opposite the sun in the sky, on the night of the 14th. It will then rise at sunset, cross the meridian in the south at 1:00 a.m., then set at sunrise. Because of the directional way that the rings reflect light back toward the sun, observations made through a telescope will show that the rings brighten dramatically with respect to the planet within a day of the opposition. After a few nights, the appearance of the rings will be back to their usual level, only as bright as the planet itself.
The brightest of all the planets, Venus, blazes in the eastern sky starting shortly after it rises at about 3:10 a.m. A telescope now shows Venus displaying a gibbous phase.
The waning moon rises at 11:55 p.m. on the 14th and at 3:43 a.m. on the 21st. Its phase changes from gibbous to last quarter on the 17th, and then is crescent until the new moon on the 23rd. The moon is paired with Venus on the mornings of the 20th and 21st.
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 free 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, July 29th.
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From Griffith Observatory, I’m Anthony Cook, and I can be reached at griffithobserver@gmail.com.