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This is the Griffith Observatory Sky Report through November 1, 2017. Here’s what’s happening in the skies of southern California.
The moon waxes from crescent to first quarter on the afternoon of October 27th, and afterward it is waxing gibbous as it approaches full on November 3rd. The moon lights the sky for an increasingly longer period each successive night. As a result of this, the moon sets at 10:39 p.m. on October 25th and at 4:18 a.m. on November 1st. The moon is one of the objects featured through Griffith Observatory’s public telescopes.
The planet Saturn, in the constellation Ophiuchus the Serpent Bearer, can be seen low in the southwestern sky during the evening twilight. A telescope is required in order to observe Saturn’s beautiful system of rings. The planet sets at about 9:00 p.m., and soon it will be lost from view in the glare of the sun.
The main-belt asteroid 7 Iris will be at opposition, opposite the sun in the sky, on October 29th. Iris will appear as bright as a 6.5 magnitude star, and should be easily visible through binoculars when it is at its highest point in the sky at 1:00 a.m. It will slowly change position against the stars of Aries the Ram, near the base of the broad triangle made by the brightest stars of Aries. Iris can be identified by using a finder chart published on the In The Sky Website.
The brightest star of the nighttime sky is Sirius in the constellation Canis Major the Large Dog. Sirius is sparkling and eye-catching after it rises above the east-southeastern horizon at midnight and until it crosses the meridian in the south shortly before dawn. The star is 8.6 light-years away. Our sun, for comparison, is only 8.3 light-minutes away. Sirius is a double star. It has a companion white-dwarf star called Sirius B that orbits the brighter star, Sirius A, once every 50 years. Currently, Sirius B can be spotted with a 10-inch telescope, and it is located 12 arcseconds to the east (and slightly north) of the Sirius A. Sirius B is hard to see, however, as it is 10,000 times fainter than its blazing companion!
The brightest planet, Venus, rises above the eastern horizon at about 5:40 a.m. The planet Mars, glowing with an orange hue, appears about 15 degrees to the upper right of Venus. Both planets are on the far side of the sun, nearly as far from the Earth as they can be, and currently look small even through large telescopes.
On the morning of Wednesday, October 29th, the International Space Station will cross the dawn skies from the southwest to the northeast between 6:25 and 6:32 a.m. The orbiting laboratory should outshine Venus when it appears overhead at 6:29 a.m.
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, November 18th.
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From Griffith Observatory, I’m Anthony Cook, and I can be reached at griffithobserver@gmail.com.