This is the Griffith Observatory Sky Report through October 25, 2017. Here’s what’s happening in the skies of southern California.
The moon is new on the 19th. On Friday the 20th, look for the moon’s slender crescent just above the western horizon, starting at 6:38 p.m., the end of civil twilight. The moon waxes and will move higher in the sky after sunset each successive night that follows through the 27th, when its phase is first quarter. Moonset occurs at 7:11 p.m. on the 20th and at 10:39 p.m. on the 25th.
The planet Saturn resembles a bright golden star that glows in the southwest as the sky darkens. The moon appears close to Saturn on the 23rd and 24th. The ringed planet sets shortly after 9:00 p.m.
The absence of pre-dawn moonlight makes this an excellent year to watch the annual Orionid meteor shower. The peak of the shower should occur on Saturday morning, the 21st, and can be observed starting at midnight and as it steadily strengthens until 5:40 a.m., the start of dawn. From a dark, rural location from where the Milky Way is easily seen, up to 25 Orionid meteors per hour appear to streak from the upraised club of the constellation Orion the Hunter. The meteors are caused when tiny fragments that were shed centuries ago by the famous comet Halley collide with earth’s atmosphere. Only warm clothing, a sleeping bag, and a reclining deck chair are all that are needed to watch the shower. Because urban light pollution hinders the observation of meteors, no observing activities will take place at Griffith Observatory, and Griffith Park will not be open during the pre-dawn hours.
The brightest planet, Venus, can be seen close to the eastern horizon when dawn starts. The much fainter planet Mars, now about as far from the earth as it can be, is visible to the upper right of Venus and can be recognized by its orange hue. Mars will gradually brighten over the next nine months until, in late July, it makes a relatively close, 36 million mile approach to the earth. It will then appear brilliant in the midnight sky.
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, October 21st.
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From Griffith Observatory, I’m Anthony Cook, and I can be reached at firstname.lastname@example.org.