Griffith Observatory Sky Report for the week ending Wednesday, December 7

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Here is what’s happening in the skies of Southern California:

The waxing moon now dominates the nighttime hours this week. Its phase grows from crescent to first quarter on the night of Thursday, December 1, and is gibbous for the remainder of the week. The moon lights the sky for a longer period each successive night, with its setting time advancing from 10:36 p.m. to 4:08 a.m. between November 30 and December 7.

Venus, the brightest planet, is eye-catching in the southwest sky after sunset. The planet is on the far side of its orbit with respect to the sun and through a telescope looks small and almost fully lit. Venus sets at about 6:30 p.m.

Planet Jupiter, in Aries the Ram, is high in the east as the sky darkens. The giant planet appears only slightly fainter than Venus and has a noticeably yellow hue. Jupiter is best placed for viewing at about 8:45 p.m. when it is 66 degrees high in the south. The planet sets in the west shortly after 3:00 a.m. The gibbous moon passes Jupiter on the nights of the 5th and 6th.

The glittering object low in the southeast at about 10 p.m. is the brightest nighttime star, Sirius, of Canis Major, the Big Dog. Sirius crosses the meridian 39 degrees high in the south at 1:40 a.m. Motion of unstable air above us can make Sirius twinkle and appear to shimmer in bright colors, especially when it is close to the horizon.

The orange planet Mars is the brightest object in the middle of Leo the Lion, and is best seen at 6:00 a.m., about 45 minutes before sunrise, when it is 62 degrees high in the south. Mars appears over 7 arc-seconds across, just large enough to see the planet’s north polar cap and dark markings scattered across its rust-hued deserts through a telescope of 8 inches or greater diameter. The planet is also showing its greatest amount of phase, similar to a gibbous moon three days before full.

6:00 a.m. is also the best time to see the ringed planet, Saturn, now in Virgo the Maiden. Saturn is then 35 degrees high in the southeast, elevated enough to get a clear view of its rings through a telescope and are now tilted 14 degrees in our direction.

The International Space Station should make a pass directly over Los Angeles before sunrise on Sunday, December 4. The ISS is expected to cross the sky from northwest to southeast between 6:21 and 6:28 a.m., P.S.T., and should be directly overhead a few seconds before 6:25 a.m. The brightness of the satellite may exceed that of Venus.

Free public viewing of the sun during the day and of the moon, planets, and other celestial objects at night, is available in clear weather, five nights a week (Wednesday through Sunday) through Griffith Observatory’s telescopes before 9:45 p.m. Check our website for our schedule. The next public star party of the Los Angeles Astronomical Society and the Sidewalk Astronomers is scheduled for Saturday, December 3. Griffith Observatory and the astronomy clubs will also host viewing of the total lunar eclipse from 4:30 a.m. until sunrise on Saturday, December 10. This eclipse will be described in next week’s sky report.

The Sky Report is updated every Wednesday. It can be read — and now, heard — on our website by following the Sky Information links. From Griffith Observatory, I’m Anthony Cook, and I can be reached at

— Anthony Cook, Astronomical Observer