This is the Griffith Observatory Sky Report for the week ending Wednesday, June 13, 2012. Here is what’s happening in the skies of Southern California:
With the planet Venus now out of the evening sky, innermost planet Mercury appears during twilight, while Mars and Saturn are nearly tied for the position of brightest nighttime planet.
Binoculars will help you to find Mercury when it first appears after sunset on the 6th. Look for it 5 degrees above the horizon in the west-northwest at about 7:30 p.m. As the month goes on, Mercury appears a little higher each successive evening when viewed 30 minutes after sunset.
Mars is in Leo the Lion and shines with an orange cast. The planet can be found about midway between the south-southwest horizon and overhead as darkness falls. On the 12th, the distance between earth and Mars grows to 140 million miles, or 1.5 Astronomical Units (1½ times the distance to the sun). Mars sets in the west at 1:00 a.m.
Saturn also becomes visible as the sky grows dark, midway between the south-southeast horizon and overhead. It is 5 degrees above Virgo the Maiden’s brightest star, Spica. Saturn outshines the star and has a golden hue. The north side of Saturn’s ring plane is tilted 13 degrees in our direction. Saturn is now featured through Griffith Observatory’s telescopes. Saturn can be followed until it sets in the west at 2:40 a.m.
The time between nightfall and moonrise lengthens as the week progresses. The moon’s rising time advances from 10:22 p.m. to 1:46 a.m. between the 6th and the 13th. The moon is waning, its phase changing from gibbous to last quarter on the 11th, then to crescent on the following mornings this week.
The International Space Station makes two passes high above Los Angeles this week. The first is on the evening of Wednesday, June 6. The space station, outshining anything else then in the sky, will cross the sky from southwest to northeast between 9:17 p.m. and 9:23 p.m., P.D.T. It reaches its apex, 60 degrees high in the south-southwest at 9:20 p.m. The second pass is on Friday morning, June 8. The ISS will cross the sky from northwest to southeast between 4:29 a.m. and 4:35 a.m., P.D.T., and is 76 degrees above the southeast horizon at 4:32 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 five days a week (Wednesday-Sunday) through Griffith Observatory’s telescopes before 9:30 p.m. Check our website for our schedule. The next public star party of the Los Angeles Astronomical Society and the Sidewalk Astronomers is scheduled for Saturday, June 23.
From Griffith Observatory, I’m Anthony Cook, and I can be reached at griffithobserver@gmail.com.