Today is Friday the 13th of September, which for some, is a mystical sort of day. In addition to the mystery that surrounds Friday the 13th, tonight will also see a full moon. The last time a full moon and Friday the 13th coincided nationwide was October of 2000. On the website Earthsky.org they explain that for those of us in the Northern Hemisphere, the full moon tonight counts as the closest full moon to the September autumnal equinox, making it a Harvest Moon. What makes a moon, a full moon? The moon appears full to the eye for a few to several days in succession, when actually it’s only truly full for a fleeting instant. Astronomically speaking, the moon is full at the moment that it’s exactly 180 degrees opposite the sun in ecliptic longitude. At time zones in the eastern United States, the full moon technically falls on Saturday, September 14, at 12:33 a.m. EDT. But it falls on Friday, September 13 at all other U.S. time zones. The next time it will happen again after today will be August in the year 2049.
