LISTEN to this week’s Sky Report
This is the Griffith Observatory Sky Report through October 28, 2015. Here’s what’s happening in the skies of southern California.
The moon is waxing gibbous until the morning of the 27th, when it is full. October’s full moon has the nickname Hunter’s Moon. The moon will be waning gibbous when it appears on the 28th.
The moon will set at 1:33 a.m., PDT on Thursday morning, October 22, before it can interfere with watching the annual Orionid Meteor shower. The meteor shower will be at its peak from moonset until dawn, at 5:39 a.m. Orionid meteors seem to stream from the club of the constellation Orion the Hunter. Orion moves from the southeast to the south between moonset and dawn. From a wilderness location in the mountains or desert, far from the glow artificial light pollution, you might see between 15 to 20 Orionids per hour. Orionids are caused by dusty particles shed by comet Halley in past centuries, and are seen each year in October when Earth is near the inbound portion of Halley’s orbit. Comet Halley is also the source of the eta Aquariid meteor shower each May.
The only bright planet visible after sunset is Saturn, in the constellation Scorpius the Scorpion. As the sky becomes dark enough to see it, at 6:45 p.m., Saturn is low in the southwest sky. Saturn sets at 8:06 p.m. on the 21st and at 7:41 p.m. on the 28th.
All of the other bright planets, Mercury, Venus, Mars, and Jupiter, can be seen in the east during dawn until about 6:30 a.m. in positions that change noticeably from morning to morning. On the 22nd, the brightest planet, Venus, is only three degrees to the upper right of the second brightest planet, Jupiter. Dimmer Mars, distinguished by its red hue, is then two degrees to the lower left of Jupiter. The innermost planet, Mercury, is eight degrees high, and is 10 degrees (the width of your clenched fist held at arm’s length) south of due east. Because of its low elevation, Mercury is the hardest to see, and it will only be half as high in the sky by the morning of the 28th. On Sunday the 25th, Venus will be one degree to the right of Jupiter, and on the 28th, Venus will mark the apex of a small, broad triangle with Jupiter to the upper right and Mars to the lower left.
The International Space Station will appear brilliant as it crosses high across the skies of Los Angeles on two evenings. The first appearance should occur on Thursday night, October 22. The ISS will appear above the northwest horizon at 7:53 p.m. and will enter Earth’s shadow just as it reaches its highest point, 50 degrees high in the west. On the following night, Friday, October 23, the ISS will appear in the northwest at 7:00 p.m. It will appear highest in the sky, 60 degrees above the northeast horizon, at 7:04 p.m., and will fade into Earth’s shadow, 17 degrees above the east-southeast horizon.
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 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 21.
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