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This is the Griffith Observatory Sky Report for the week ending Wednesday, January 28, 2015. Here is what’s happening in the skies of southern California:

Venus, the brightest planet, is visible low in the southwest during evening twilight. On Wednesday the 21st, look toward Venus at about 5:45 p.m. By that time, the sky will be dark enough to see the slender crescent moon to the right of Venus and the planet Mercury making an equilateral triangle beneath Venus and the Moon. After the 24th, Mercury will move too far below Venus and too close to the horizon to be seen.

Increasing moonlight will end the period of best dark-sky viewing of comet C/2014 Q2 Lovejoy on the 22nd. The comet is high in the sky as darkness falls. This week, comet Lovejoy is easy to find through binoculars between 13 and 23 degrees northwest of the Pleiades star cluster in Taurus. It appears as a round, softly glowing cloud half as wide as the apparent size of the moon.

Jupiter, in Cancer the Crab, is bright and eye-catching shortly after it rises above the eastern horizon at about 6:30 p.m. Jupiter is visible nearly all night long, appearing 72 degrees high in the south at 1:00 a.m., and then moving low over the western horizon at dawn. On Friday, January 23, telescope-equipped observers will be treated to a very rare view of the shadows of three of Jupiter’s four large Galilean moons as they cross (transit) Jupiter’s disk at the same time. This “triple-shadow-transit” starts at 10:25 p.m. when the shadow of Europa appears on Jupiter’s disk, joining those of Callisto and Io, already in transit. It ends when Io’s shadow leaves Jupiter’s disk at 10:54 p.m. A little earlier, between 9:40 and 9:59 p.m., observers can see Io darken while near the center of Jupiter’s disk as it moves into the shadow cast by more distant Callisto. At the same time the shadows of Callisto and Io will merge on the disk of Jupiter. A complete time line and an animated preview of the event are available on Griffith Observatory’s Livestream channel, which will also show an actual live video stream of the event through Griffith Observatory’s 12-inch Zeiss refractor, weather willing. Another triple shadow conjunction will not be visible from the longitude of Griffith Observatory until 2032.

The waxing moon is crescent until it reaches first quarter on the night of the 26th. It is gibbous through the remainder of the week.

The planet Saturn appears bright and golden in the southeast as dawn starts. It appears 10 degrees above the orange star Antares of Scorpius the Scorpion. A telescope can provide a view of the northern face of the planet’s magnificent ring system, now tilted 25 degrees from edge-on.

The International Space Station will pass directly over Los Angeles on Tuesday morning, the 27th. At times, the ISS will outshine Jupiter as it emerges from Earth’s shadow 28 degrees above the northwest horizon at 5:43 a.m. and makes its way to the southeast horizon, 5 minutes later. The ISS appears overhead from Los Angeles at 5:45 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 our 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 24.

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.