Aug. 29 Supermoon Kicks Off Three Months of Supersized Full Moons

Summary: The Aug. 29 supermoon kicks off three months of supersized full moons as 2015's first supermoon; Great Lakes tribes know it as the sturgeon moon.

closeup of Full Moon: NASA/Sean Smith, Public Domain, via NASA.gov

A sextet of waxing gibbous moons, shining nightly with increasing brightness amid clear skies, yields to a full supermoon Saturday, Aug. 29, 2015. The waxing gibbous phase represents 51 to 99 percent illumination of the lunar disc, as viewable to Earthlings.

August 2015 celebrates the month’s last waxing gibbous moon, occurring Friday the 28th, in a crescendo of brightness, with a 98 percent-lit disc.

As the fourth phase of the monthly eight-phase lunar cycle, a full moon forms a straight line, known as syzygy (Ancient Greek: σύζυγος, suzugos, “yoked together”), with the Earth and the moon. The full moon is positioned on the opposite side of the Earth from the sun.

The opposite of full moon syzygy in positioning between Earth and sun, new moon syzygy complements full moon syzygy.

In the moon’s monthly elliptical orbit around the Earth, perigee designates the closest distance, as measured center-to-center in the two celestial bodies. Perigee is a variable figure, with proxigee representing the year’s closest perigee.

A center-to-center distance of less than 224,834 miles (361,836 kilometers) yields the moniker of supermoon in recognition of the proximity-induced optical illusion of an unusually large moon. August's perigee cozies up to Earth at a center-to-center distance of 222,631 miles (358,290 kilometers). August's perigee actually takes place Sunday the 30th at 15:24 Coordinated Universal Time (11:24 a.m. Eastern Daylight Time).

Saturday the 29th's moon crests at fullness at 18:35 UTC (2:35 p.m. EDT; 7:35 p.m. British Summer Time). With perigee in only 21 hours 11 minutes, August's full moon qualifies as a full supermoon.

Native American tribes tracked the seasons by naming monthly full moons according to events in nature.

Tribes of the Great Lakes identified August's full moon as sturgeon moon in acknowledgment of ease of catching plentiful sturgeon (family Acipenseridae) at this time.

Green corn moon, another epithet, marked the impending harvest of September's full corn moon.

The Dakotah Sioux and the Ojibway knew August's full moon as "moon when all things ripen" and blueberry moon, respectively.

August’s full supermoon passes the torch for bigness and closeness to its successor, September’s full supermoon. Occurring Monday the 28th, September’s supersized moon zooms to a center-to-center closeness of 221,753 miles (356,877 kilometers).

August's full supermoon shines brilliantly, even through cloudy veils, during its east-to-west transit across Earth's night sky.

To paraphrase "That's Amore," the 1952 Oscar-nominated song by composer Harry Warren (Dec. 24, 1893–Sept. 22, 1981) and lyricist Jack Brooks (Feb. 14, 1912–Nov. 8, 1971):
"When the Moon hits your eye like a big sturgeon pie, that's August's Moon."

August Full Moon aka Sturgeon Moon ~ sub-adult Pallid Sturgeon (Scaphirhynchus albus), Neosho National Fish Hatchery Visitor Center, southwestern Missouri: USFWSmidwest (U.S. Fish and Wildlife Service - Midwest Region), CC BY 2.0, via Flickr

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

sub-adult Pallid Sturgeon (Scaphirhynchus albus), Neosho National Fish Hatchery Visitor Center, southwestern Missouri: USFWSmidwest (U.S. Fish and Wildlife Service - Midwest Region), CC BY 2.0, via Flickr @ https://www.flickr.com/photos/usfwsmidwest/14959493226/

full moon closeup: NASA/Sean Smith, Public Domain, via NASA @ http://www.nasa.gov/centers/langley/images/content/528691main_Super_Moon.jpg

For further information:

"August 2015 Moon Phases." Farmers Almanac > Calendars > Moon Phase Calendar.
Available @ http://farmersalmanac.com/calendar/moon-phases/

"Full Moon for August 2015." The Old Farmers' Almanac > Moon & Astronomy.
Available @ http://www.almanac.com/content/full-sturgeon-moon-augusts-moon-guide

McClure, Bruce. "First of 3 supermoons on August 29." EarthSky > Tonight for August 29, 2015.
Available @ http://earthsky.org/tonight/august-29-supermoon-first-of-three-supermoons

McClure, Bruce. "Moon swings to perigee -- closest point -- on August 30." EarthSky > Tonight for August 30, 2015.
Available @ http://earthsky.org/tonight/moon-swings-to-perigee-closest-point-on-august-30

"Today - Saturday, August 29, 2015." MoonGiant > Moon Phase.
Available @ http://www.moongiant.com/phase/8/29/2015