Astro Bob: August heavenly highlights — 2 full moons bookend year's best meteor shower

Gobs of good stuff is happening this month, sandwiched between two full moons.

On Aug. 1 is the sturgeon moon, followed 29 days later by the blue moon. Full moons normally occur once a month, or three per season. Early last century, a blue moon was the name given to the third full moon in a season that had four full moons — one more than normal.

That changed midcentury due to a misinterpretation of the original meaning by a writer for Sky & Telescope magazine, who defined a blue moon as the second full moon in a single calendar month. Blue moons occur every two to three years. It also happens that both sturgeon and blue moons will be closer to the Earth than usual, making them supermoons. That's a lot of moonlight for one month!

Prospects are excellent for the annual Perseid meteor shower, which peaks the night of Aug. 12-13. Venus departs the evening sky in August but returns to view at dawn by month’s end. Mars now shines at its faintest for the year at magnitude 1.8. Use binoculars to spot it very low in the western sky in mid-twilight. Mercury may also be visible at about 8 degrees to the lower right of Mars during the first few nights of August about 25-30 minutes after sunset.

Saturn is the easiest evening planet to see. Watch for it to make its first appearance in the southeastern sky around 10 p.m. local time, followed by brilliant Jupiter two hours later.

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On Aug. 24, the moon will pass directly in front of the bright star Antares in Scorpius and cover it for about an hour. The event is called an occultation, and you can watch the star wink out with your eyes or through a pair of binoculars. Not to miss!

Aug. 1: Full sturgeon moon. Gets its name because this time of year was good for catching sturgeon in the Great Lakes. The August full moon occurs just 11 hours after lunar perigee, when the moon is closest to Earth. Being closer, it will appear a little brighter and larger than usual, the reason it’s also called a supermoon. To find your local moonrise time, go to timeanddate.com/moon.

Aug. 3: Waning gibbous moon in conjunction with Saturn 4 degrees to its lower right

Aug. 8 (a.m.): Last quarter moon. Beautiful, close conjunction of Jupiter and the moon this morning, best from 1 a.m. local time till dawn. The duo will be just 1.5 degrees apart.

Aug. 9 (a.m.): Thick, waning crescent moon near the Pleiades star cluster

Aug. 12-13: Peak of the Perseid meteor shower. The moon will not interfere. From the city, you’ll see around 20-30 meteors per hour and double that from the countryside. You can face any direction to watch the shower. Viewing starts around 10 p.m. local time but is typically best from midnight till dawn.

Aug. 13: Venus is at inferior conjunction when it passes between the sun and Earth. Temporarily swamped by the sun’s glare, it won’t be visible until later this month.

Aug. 15 (a.m.): Razor-thin crescent moon (less than 24 hours shy of new moon) hovers low in the eastern sky about 45 minutes before sunrise.

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Aug. 16: New moon

Aug. 18: Crescent moon and Mars in conjunction low in the western sky. Mars will sit less than a degree below the moon. Use binoculars.

Aug. 24: First quarter moon

Aug. 24: The half-moon covers Antares, the brightest star in Scorpius for much of the U.S. and Canada. The occultation occurs around 10 p.m. local time out east, around 9 p.m. in the Midwest and 8 p.m. in the mountain states. See Astro Bob’s Astronomy on Facebook for details.

Aug. 27: Saturn at opposition and closest to Earth for the year. The ring king rises in the southeastern sky in Aquarius around sunset and shines all night. Even a small telescope magnifying 30x will show the rings along with Titan, the planet’s brightest moon.

Aug. 28-31: Venus returns to view in the morning sky. Look low in the east starting about an hour before sunrise.

Aug. 30: Full moon/blue moon/supermoon. In the modern era, the second full moon in a single month is called a blue moon. This blue moon will be the year’s largest full moon since perigee occurs just nine hours before the full moon.

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