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This is the Griffith Observatory Sky Report through August 22nd, 2019. Here’s what’s happening in the skies of southern California.

The planets Jupiter and Saturn are perfectly positioned for viewing as soon as the sky starts to darken.

Jupiter is now the brightest object visible between sunset and moonrise. It is close to the meridian in the south during evening twilight and it occupies the constellation Ophiuchus the Serpent Bearer. Saturn is located to the lower left of Jupiter, in the southeast sky and it gleams as a bright golden star on the eastern side of the constellation Sagittarius the Archer.

Binoculars may let you glimpse the four largest of Jupiter’s many moons, while a telescope will let you observe the details of Jupiter’s clouds. Jupiter’s colorful oval storm, the Great Red Spot, is visible through telescopes in the Pacific Time zone at 8:30 p.m. on the 16th, 18th, and 20th. A telescope may also let you observe the shadow of Jupiter’s large moon Io as it crosses Jupiter’s disk between 8:03 and 10:14 p.m. on the 19th.

A telescope will also make it possible to see the rings of Saturn. Several of Saturn’s moons may also be visible. They appear as stars of different brightness scattered at different distances outside of Saturn’s rings. As also is the case with Jupiter’s moons, observations of Saturn’s moons made nightly with a telescope will make their orbital motion obvious.

The brightest stars visible at nightfall include the bright orange Arcturus in Boötes the Herdsman, high in the west-northwest and to the left of the Big Dipper, and Regulus in Leo the Lion, low in the western sky. In the eastern half of the sky, look for the “Summer Triangle” consisting of Vega in Lyra the Lyre, just east of being directly overhead, Deneb in Cygnus the Swan, high in the northeast, and Altair in Aquila the Eagle, in the southeast. Orange-tinted Antares in Scorpius the Scorpion is in the south and just to the lower right of Jupiter.

The moon is full on the morning of the 15th, and following that it makes its gradual exit from the early evening sky. Between the nights of the 15th and the 22nd, the moon’s phase wanes from gibbous to last-quarter while its rising time changes from 8:10 p.m. to 11:44 p.m.

Beginning at about 5:30 a.m., the innermost planet, Mercury, can be seen briefly against the brightening sky. It is just above the east-northeast horizon, and it is directly below the brightest stars in the constellation Gemini the Twins, Castor and Pollux. Mercury’s gleam is similar to the brightness of either of these stars.

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 7 between 2:00 p.m. and 9:30 p.m.

Follow The Sky Report, All Space Considered, and Griffith Observatory on Twitter for updates on astronomy and space-related events.

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