Description: Viral postings / Internet meme
Circulating since: Perennially
Status: True, with hype (see details below)
As posted on Facebook, June 6, 2013:
Many call the June 2013 full moon a supermoon. The upcoming full moon on June 23, 2013, will not only be the closest and largest full moon of the year. It'll also present the moon's closest encounter with Earth for all of 2013.
As posted on Facebook, June 10, 2013:
SUPER MOON - June 23, 2013
This year's largest and closest "Super Moon" will occur on June 23, 2013. This super full moon is not only the closest and largest full moon of the year, it also presents the moon's closest encounter with earth in a long time.
Analysis: The popular term "supermoon" is of fairly recent coinage (the term "perigee moon" is preferred by astronomers) but there's nothing new about the phenomenon to which it refers: a full moon coinciding with the perigee (the point closest to earth) of the moon's elliptical (oval-shaped) orbit around the planet.
Though the viral graphic above suggests that supermoons are fairly rare, according to NASA they're actually quite common, with the moon turning full within a few hours of perigee an average of once a year (last year's supermoon on May 6, 2012 generated comparable buzz).
Also, not to spoil anyone's enjoyment of the event, but while the full moon can appear as much as 14% larger and 30% brighter than normal at perigee, it's not such a major difference that everyone, everywhere will be able to perceive it. Truth be known, the supermoon phenomenon has been somewhat overblown by the media. What hasn't these days?
More spacey urban legends:
• North Pole Sunset
• Double Sunrise on Mars?
• NASA and the Missing Day in Time
• What Is a Blue Moon?
• Can You Balance Eggs on the Equinox?
• Close Encounter with Mars on August 27
Sources and further reading:
Most Super 'Supermoon' of 2013 on June 22-23
EarthSky.org, 2 June 2013
Super Full Moon
NASA Science News, 16 March 2012
The Supermoon Stuff? AGAIN?
Bad Astronomy blog, 2 May 2012
How Big Is the Moon?
Last updated 06/10/13