Once in a blue moon: Kick off your Labor Day with the last blue moon ’til 2015

Know what makes this Friday special? It’s not that it’s the start to a glorious three-day weekend (although that certainly helps). Rather, Friday marks the last blue moon you can expect to see until 2015.

Once in a blue moonNow, we don’t want to mislead you. “Blue moons” aren’t so-named because the moon turns azure or gives off a blue-y radiant hue. Instead, the term “blue moon” refers to the fourth full moon in a season or the second full moon in a month. We had a full moon Aug. 1, making tonight’s mooning a blue one.

The last blue moon was on New Year’s Eve on Dec. 31, 2009, and the next one isn’t projected to happen until July 31, 2015. So if you buy into all that Mayan apocalypse stuff, this may well be your last chance.

Blue moons occur because our calendar months don’t sync exactly with the orbit of the moon (it takes the moon 29.5 days to move from full to new to full again, and calendar months are usually longer than that because they are based on the solar cycle), although many astronomers contend that the modern definition came about due to an old error in the Maine Farmer’s Almanac. Lucky for us, the error made the blue moon a far more frequent thing to behold.

So whether you’re more interested in a neon moon or the actual moon, we hope you take some time to duck outside tonight and appreciate this astronomical rarity. The moon will be at its fullest at 8:58 p.m. Central Standard Time.

Where do we recommend viewing the moon? From the George Observatory, of course!