LISTEN to this week’s Sky Report
This is the Griffith Observatory Sky Report through January 13, 2016. Here’s what’s happening in the skies of southern California.
The innermost planet, Mercury, becomes visible at about 5:30 p.m. through the 8th. At 5:30 p.m., Mercury is about 5 degrees above the southwest horizon, and will set 30 minutes later. Binoculars will help you to spot the planet against the twilit sky. After the 8th, Mercury will appear too close to the sun to observe until it reappears before sunrise during the last ten days of January.
Brilliant planet Jupiter, in the constellation Leo the Lion, rises above the eastern horizon at about 10:00 p.m. Jupiter is 60 degrees high and due south when it crosses the meridian at 4:00 a.m. A telescope is needed to see the details of Jupiter’s cloudy face, but steadily held binoculars are sufficient to glimpse the giant planet’s four largest moons.
Orange planet Mars, in the constellation Virgo the Maiden rises at about 1:15 a.m., and is best placed for observation when it is high in the south at the start of dawn, four hours later. Mars appears about as bright as Virgo’s brightest star, Spica, visible 10 degrees to the right of Mars, but the rusty hue of Mars contrasts with the frosty blue-white color of Spica. Mars is now more than three times as far away from Earth as it will be at its closest approach in late May, so it is still difficult to see details on the surface of the planet through nearly any telescope. The easiest detail to see now is the planet’s brilliant white north polar cap. Northern hemisphere summer started on Mars on January 3rd, so observers should be able to notice the shrinking of the polar cap over the next few months as the sun warms it. The cap is composed mostly of frozen carbon dioxide.
The brightest planet, Venus, appears above the east-southeast horizon before 4:30 a.m. Venus appears close to the golden planet Saturn, and on the 9th the two planets are separated by only half a degree, the angle equal to the apparent diameter of the moon.
The slender crescent moon joins Venus and Saturn on the 7th, and can be seen in the morning sky until the 8th. New moon occurs on the evening of the 9th. The waxing crescent moon can be seen low in the west-southwest after sunset starting on the 10th, and by the 13th it sets at 9:20 p.m.
The absence of bright moonlight in the early morning makes this the prime time for observing comet Catalina C/2013 US10. Comet Catalina is glowing steadily at magnitude 6, and can be seen in binoculars. The comet is well placed for viewing in the northeastern sky between midnight and dawn, and is moving northward along a line between the bright star Arcturus of the constellation Boötes the Herdsman, and the star Alkaid that marks the end of the Big Dipper’s handle. Comet Catalina crosses the boundary from Boötes to Canes Venatici The Hunting Dogs, on the 9th. A finder chart is available from Sky and Telescope.
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, January 16.
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