What is a supermoon? The word supermoon didn’t come from astronomy. Instead, it came from astrology. Astrologer Richard Nolle of the website astropro.com takes credit for coining the term supermoon. In 1979, he defined it as:
…a new or full moon which occurs with the moon at or near (within 90% of) its closest approach to Earth in a given orbit (perigee). In short, Earth, moon and sun are all in a line, with moon in its nearest approach to Earth.
By this definition, according to Nolle, there are 4-6 supermoons a year on average.
The full moon of November 14, 2016 is not only the biggest, closest and brightest supermoon of this year. It’s the closest supermoon since January 26, 1948. Should you watch for this full moon on the night of November 14? Sure, and, if you do, it’ll be beautiful. But, for us in the Americas the moon is closer to full on the night of November 13.
The moon turns precisely full on November 14, 2016 at 13:52 UTC. This full moon instant will happen in the morning hours before sunrise November 14 in western North America and on many Pacific islands, east of the International Date Line. (See worldwide map below.)
In Asia and Australia, the moon turns precisely full during the evening hours of November 14. In New Zealand, it actually happens after midnight November 15. Around the longitudes of Europe or Africa, look both nights.
Better yet … everyone, look both nights!
The moon will look plenty full and bright all night long on both nights – November 13 and 14 – as it rises in the east around sunset, climbs highest up around midnight, and then sets in the west at or near sunrise.
The moon won’t come this close to Earth again until November 25, 2034.
Astronomers call this sort of close full moon a perigee full moon. The word perigee describes the moon’s closest point to Earth for any given month. Five years ago – when the closest and largest full moon fell on March 19, 2011 – many began using the term supermoon. In the following years, we heard this term again to describe the year’s closest full moon on May 6, 2012, and again on June 23, 2013, and again on August 10, 2014, and yet again on September 28, 2015.
Now the term supermoon is being used a lot, and, personally, we approve! It’s a good descriptive term for the closest full moons, much easier to remember than perigee full moon.
Last month’s full moon – on October 16, 2016 – was also a supermoon. But the November full moon is even more super! In other words, the time of full moon falls even closer to the time of the moon’s closest point to Earth.
The next supermoon falls on December 3, 2017.