This is the Griffith Observatory Sky Report through August 3rd, 2016. Here’s what’s happening in the skies of southern California.
The planet Mercury can be spotted about 9 degrees above the western horizon at the start of nautical twilight that happens at 8:20 p.m. You can estimate the 9-degree angle by comparing it to the approximately 10 degree angular size of your clenched fist when held out at arm’s length. If the air is very clear, you may also spot the brilliant planet Venus. Venus will be 4 degrees above the horizon, and about 7 degrees to the lower right of Mercury. Binoculars should greatly aid in finding these planets.
The planet Jupiter, in the constellation Leo the Lion, is the most obvious object in the west-southwest sky, and is located to the upper left of Venus and Mercury. Extending the imaginary line between Venus and Jupiter to the south will bring you the bright orange planet Mars in the constellation Libra the Scales, and the golden planet Saturn in Ophiuchus the Snake Bearer. This year, July 27 to August 24 is a rare period in which all five naked eye planets are visible in the sky at the same time. Venus will gradually move higher in the sky and should be easier to see by August 7, so don’t be discouraged if you don’t succeed in seeing all five before then.
Mars and Saturn are currently the planets best placed for telescopic observation. Through a telescope, Mars now displays a gibbous phase, and its disk appears about 13 arcseconds in diameter, or 68 percent as wide as it did when it was closest to earth in June. The most recognizable dark marking on Mars, the triangular region (actually a volcanic plain) called Syrtis Major, is currently facing Los Angeles in the early evening. Saturn also is perfectly positioned for observations of its magnificent ring system. Mars and Saturn are currently featured through the public telescopes at Griffith Observatory.
The waning crescent moon can be seen in the early morning sky until August 1st. The moon is new on August 2nd, and it will become visible in the evening sky starting on the 4th.
The International Space Station will make a spectacular pass over Los Angeles on Wednesday evening, July 27th. The space station will easily outshine Jupiter as it crosses the sky from the southwest to the northeast between 8:41 and 8:48 p.m., PDT. From Griffith Observatory, the ISS will appear at its highest, 75 degrees above the southeast horizon at 8:44 p.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 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, August 6th.
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From Griffith Observatory, I’m Anthony Cook. After August 7th, I can be reached at email@example.com