The last full moon of the decade occurs tonight at 12:12 a.m. Eastern Standard Time (5:15 a.m. UTC) on December 12, 2019.
This year, December’s Full Moon on the 12th is bad luck for night skywatchers on Friday the 13th. That’s because the bright nearly-full moon will wash out the Geminid Meteor shower that peaks on December 13 and 14.
On Florida’s east coast, the Full Moon will rise over the Atlantic Ocean around 5:14 p.m. Eastern Daylight Time on Wednesday, December 11, 2019, and set the following morning around 7:21 a.m., with some slight time variation (+/- 20 minutes) depending on the viewer’s exact location in Florida.
The moon will be at 100% full illumination during the full moon peak at 12:12 a.m. EST on Thursday, December 12.
Low hanging moons near the horizon appear larger to humans. So, the Full Moon will appear biggest to the naked eye on the U.S east coast during and just after the moonrise.
According to the Farmer’s Almanac, December’s Full Moon has the seasonal of “Full Cold Moon,” “Long Night’s Moon” and the “Moon Before Yule.”
December’s full moon is often the closest full moon to the longest night of the year on the Winter Solstice.
The number 12 is significant to the moon because there are 12 months in a calendar year based on roughly 12 full moons occurring in the year.
For math nerds, the number 12 is considered a sublime number, one “that has a perfect number of divisors, and the sum of its divisors is also a perfect number.”
Perhaps that is why ancient mathematicians chose an “hour” to represent 1/12th of the day and 1/12th of the night and 12 inches in a foot.