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This is the Griffith Observatory Sky Report through August 22nd, 2018. Here’s what’s happening in the skies of southern California.
Four bright planets and the moon remain ideally placed for observing during the first half of the night.
The brightest planet, Venus, blazes in the west-southwest after sunset. Through a telescope, Venus appears crescent. The crescent phase is the result of the planet’s position nearly between the Earth and the sun; most of the daytime side of Venus is turned away from us. Venus sets at about 9:30 p.m.
Jupiter, the second brightest planet, is to the left of Venus in the southwest sky. The star just below it is Zubenelgenubi in the constellation Libra the Scales. The four largest of the planet’s 79 known moons are bright enough to see in binoculars, and they appear as tiny points of light clustered very close to the bright glow of the planet. Binoculars will also reveal Zubenelgenubi to be a close pair of stars, an example of a double-star. In a telescope, Jupiter is shown covered with banded clouds and oval storms, including the famous Great Red Spot. Currently pumpkin-colored, the Great Red Spot will face observers on the west coast at 9:00 p.m. on the 16th, 18th, and the 21st. Jupiter sets at about 11:30 p.m.
By 8:30 p.m., the sky is dark enough to see the planet Saturn high in the south-southeast in Sagittarius the Archer, far to the left of Jupiter. Although it appears bright, the gleam of Saturn is much fainter than that of Jupiter, and its yellow hue is deeper than Jupiter’s. Saturn is highest in the sky at 9:30 p.m., when it crosses the meridian 33 degrees above the south point of the horizon. It sets five hours later in the west-southwest. The rings of Saturn are thrilling to see through nearly any telescope.
The orange glow of Mars, in Capricornus the Sea Goat, outshines Jupiter from low in the southeast sky after sunset. Look south at 11:00 p.m. to see Mars at its highest. The planet is 39 million miles away, only 4 million miles farther than it was at its closest, at the end of July. It is still an interesting object to examine through most telescopes. Its white polar caps are easy to see. The dust storm that blanketed Mars starting in late May is subsiding, but the planet’s dark markings remain somewhat washed out in appearance, and are harder than usual to see.
The moon waxes from crescent to first quarter on the night of the 17th. After that, it is gibbous before the full moon on the 26th. On the 15th, the moon is above Spica, the bright star of Virgo the Maiden. It is near Jupiter on the 16th and 17th. On the 18th, it is located between Jupiter and Venus, to the right, and Saturn and Mars, to the left. It is also above the bright orange star Antares, in Scorpius the Scorpion. The moon moves next to Saturn on the 20th. On the 22nd, its will appear above Mars.
Free views of the Sun during the day and of the moon and planets 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, August 18.
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.