Full Sturgeon Moon or 'Blue Moon' lights up the night sky
Tuesday night's full moon was a blue moon, according to one definition of the term. Most know a blue moon as the second in a calendar month, but an earlier definition classified it as the third full moon in a season with four full moons (most seasons have just three full moons). Read more about the history of the debate over the two definitions at EarthSky.org or Space.com. Whether you consider it blue or not, it's also known as the Full Sturgeon Moon, Green Corn Moon or Grain Moon.
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Full Sturgeon Moon
A full moon rises over the American flag during Tuesday's baseball game between the Kansas City Royals and Chicago White Sox on August 20, 2013, at Kauffman Stadium in Kansas City, Missouri.