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This is the Griffith Observatory Sky Report through September 5^th, 2018. Here’s what’s happening in the skies of southern California.

The brightest planet, Venus, is currently visible about 20 degrees high in the southwest sky at sunset. Through a telescope, the planet now displays a crescent phase. Venus sets at about 9:00 p.m.

Starting half an hour after sunset, the planet Jupiter becomes easily visible. Although Jupiter is fainter than Venus, it is still a brilliant object, and it appears to the upper left of Venus in the constellation Libra the Scales. Jupiter sets about an hour after Venus, in the west-southwest. In coming weeks, Jupiter will become too low in the sky to see its details clearly with a telescope, but for now its four bright moons and major cloud features remain easy to observe before 9:00 p.m. Use high magnification to look for Jupiter’s famous oval storm, the Great Red Spot, when it faces west coast observers on August 30^th, September 2^nd, and September 4^th.

At 8:00 p.m., look far to the left of Jupiter to see the golden planet Saturn in the south, at the top of the teapot-shaped constellation Sagittarius the Archer. Saturn appears brighter than most stars, but it is considerably fainter than Jupiter. Saturn’s beautiful rings are stunning to see through telescopes. Saturn sets in the west-southwest at about 1:00 a.m.

The planet Mars begins the evening in the southeast sky. Mars has a distinctive orange hue, and its glow now is similar to that of Jupiter in brilliance. For observers with telescopes, Mars is more interesting to observe now than it was when it was closest to Earth at the end of July. This is because its atmosphere is now much clearer following the global dust storm that obscured many of the Martian surface features until recently. Mars is highest in the sky when it crosses the meridian in the south at 10:00 p.m. It sets at about 3:00 a.m.

The moon rises at 9:29 p.m. on the 29^th, and at 1:49 a.m. on September 5^th. Through this period, the moon’s phase wanes from gibbous to last quarter on the 2^nd, and after that it is crescent.

The longer absence of moonlight each night improves the conditions for observing periodic comet Giacobini-Zinner, 21/P. By the 4^th, the moon will rise after the comet is more than 20 degrees high in the northeast sky. Comet Giacobini-Zinner orbits the sun every 6.6 years, and this year it will make its closest approach to both the Earth and the Sun on September 10^th. From dark sky locations, free from urban light pollution, the comet is visible through binoculars, and it is an interesting sight through telescopes. It is currently close to the bright star Cappella in the constellation Auriga the Charioteer, and it passes only one degree south of Capella on September 2^nd. Sky observer Bob King offers detailed observing information about the comet, including a finder chart, on the Sky and Telescope website.

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, September 22^nd.

Follow the Sky Report on Twitter for updates of astronomy and space-related events.

From Griffith Observatory, I’m Anthony Cook, and I can be reached at griffithobserver@gmail.com.