LISTEN to this week’s Sky Report
This is the Griffith Observatory Sky Report through June 6, 2018. Here’s what’s happening in the skies of southern California.
The moon, now past full, is absent for a longer time after sunset from one night to the next. Its rising time advances from 9:05 p.m. on May 30th to 1:16 a.m. on June 6th. Between these dates, its phase wanes from gibbous to last quarter.
Venus, the brightest planet, and Jupiter, the second brightest planet, are easy to see as soon as the sun sets. Venus blazes above the horizon in the west-northwest, and Jupiter, in the constellation Libra the Scales, is directly opposite Venus, in the east-southeast.
As the Earth turns, the planets seem to move from the eastern to the western sky during the night. Venus slips below the horizon at about 10:30 p.m. By that time, Jupiter is high in the south, and it crosses the meridian at about 11:00, before moving to the southwest sky. Jupiter sets in the west-southwest just as dawn starts.
By midnight, two other bright planets gleam in the southeast sky. The lower and brighter planet is orange-tinted Mars, which now appears in the constellation Capricornus the Sea Goat. Its growing brightness is now nearly equal to that of Jupiter. To the upper right of Mars is Saturn, in Sagittarius the Archer, the constellation adjacent to Capricornus. The westward march of the sky causes Saturn to cross the meridian in the south before 3:00 a.m. Mars follows behind Saturn and it crosses the meridian about two hours later, after dawn begins.
The moon appears close to Saturn on the nights of May 30th and 31st. It poses above Mars on the morning of June 3rd.
All of these bright objects are fascinating through telescopes. Venus is still on the distant side of its orbit, and is only beginning to show a gibbous phase, but patient observers will have fun watching Venus gradually grow larger as it approaches Earth. The phase of Venus gradually becomes crescent by late in the summer.
Jupiter’s largest four moons can be seen in ordinary binoculars. Small telescopes, capable of at least 30-power magnification, can reveal the striped cloud structure organized into dark belts and bright zones that are created by the planet’s rapid (less than 10-hour) rotation, and high winds. Smaller disturbances, including the famous pumpkin colored oval storm called Great Red Spot, may also be seen. The Great Red Spot will face telescopes in Los Angeles at 9:00 p.m. on May 31st, June 3rd and 5th. Venus and Jupiter are the planets currently featured through the public telescopes at Griffith Observatory.
Small telescopes are also capable of showing the magnificent rings of Saturn. Farther from the planet than the rings, several of Saturn’s moons may also be seen.
Mars is now close enough to Earth to see its bright clouds and polar caps, and the dark markings scattered across the planet’s amber colored deserts, through telescopes used at high magnification. It currently appears 3/5 as large as it will when it is at its closest to Earth in late July. Mars and Saturn will move into the evening sky late in the summer.
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, June 23rd.
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.