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This is the Griffith Observatory Sky Report for the holiday period ending Thursday, January 2, 2014. Here is what’s happening in the skies of Southern California:
The winter solstice occurs at 9:11 a.m., PST on December 21. This is the start of winter in the earth’s northern hemisphere and the start of summer in the southern. The winter solstice is the moment when the sun reaches its southernmost point in the sky. This results in the shortest day of the year, with the sun rising farthest south of east, appearing lowest at noon, and setting farthest south of west as seen from the northern hemisphere. The winter season will end with the vernal equinox on March 20, 2014.
The brightest planet, Venus, will appear noticeably lower in the southwest at sunset each successive evening. The planet will swing nearly between earth and the sun on January 11. Because Venus is now the closest planet to us, it also appears large enough for its slender crescent phase to be seen in steadily held binoculars.
The second brightest planet, Jupiter, is in Gemini the Twins and rises above the east-northeast horizon shortly after sunset. Jupiter passes high overhead at about 1 a.m. before settling into the west at dawn. The disk of Jupiter and the planet’s four largest moons can be seen in binoculars, but a telescope is required to see Jupiter’s cloud patterns.
Shortly after Jupiter appears, the brilliant star Sirius of Canis Major the Big Dog, sparkles low in the southeast. Sirius is the brightest star in our sky after the sun. The motion of our atmosphere not only makes Sirius seem to twinkle, but also breaks its light into different colors. The planets of our solar system can appear brighter than Sirius (as Venus and Jupiter now do), but because they cover more of the sky than the distant stars they appear steadier in brightness than bright stars. Sirius is highest in the south around midnight, and moves into the low southwest by dawn.
Orange Mars, in Virgo the Maiden, and golden Saturn, in Libra the Scales, are best seen when dawn starts. Mars appears midway between the southern horizon and the zenith (overhead point) at that time, while Saturn is half as high in the southeast. Mars is still distant from earth and is too far away for detailed observations through small telescopes. Saturn, in spite of its great distance, is always large enough for its amazing ring system to be spotted in almost any telescope. It’s definitely worth looking at if someone in the family becomes a new telescope owner this holiday.
The waning moon changes from gibbous to last quarter on the morning of the 25th, when it appears close to Mars. The moon will pass close to Saturn in waning crescent phase on the 28th, and becomes new a few hours before the Rose Parade starts New Years day.
The International Space Station crew is scheduled to make three emergency space walks, including one on Christmas Day, to fix a critical cooling system. The ISS will make an appearance over southern California the evening of December 31. The space station, rivaling Jupiter in brilliance, will climb over the north-northwest horizon at 6:55 p.m. It will appear 46 degrees above the northeast horizon at 6:58 p.m., and should remain visible above the southeast horizon until 7:02 p.m.
Free views of the sun during the day and of the moon, planets, and other celestial objects at night, are normally available to the public in clear weather through Griffith Observatory’s telescopes Tuesday-Sunday before 9:30 p.m. During the holiday period, however, Griffith Observatory will close early on December 24 and December 31, and will be completely closed on Christmas Day. We will be open on New Year’s Day. Check our website for our schedule. The next 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, January 11.
From Griffith Observatory, I’m Anthony Cook and I can be reached at griffithobserver@gmail.com.