Full Moon

It is the full moon: the whole face of the Moon lit by the Sun. The Moon is full when it sits opposite the Sun in our sky, so we see its entire sunlit side. It rises around sunset, stays up all night and is the brightest the Moon ever gets. This happens about every 29.5 days, which is where the word “month” comes from.

The emoji is one of eight phase pictures: 🌑🌒🌓🌔🌕🌖🌗🌘. People string them together to show a whole cycle, a countdown, something loading or time passing. On its own, 🌕 is the peak of that cycle, the night when the moon looks like a glowing coin.

What does it mean when someone sends 🌕?

Usually a mood: a clear night, moonlight, a little magic. It appears in captions about late walks, long nights and romantic evenings, and in “look at the moon tonight” messages when a bright or unusually large full moon (a “supermoon”, when the Moon is closest to Earth) is in the news. Astronomy and sky-watching posts use it literally.

Next to a wolf, a bat or a Halloween pumpkin it turns eerie, because films and novels have werewolves change under a full moon. Beside a rocket in crypto or stock-market chat it means “to the moon”: the price is expected to soar. It also marks moon-related nights in many faiths, from Buddhist holy days to the Hindu Purnima, the full-moon day of each month.

Why does a full moon get its own holiday?

Because across East Asia the autumn full moon is a family reunion night. The Mid-Autumn Festival falls on the fifteenth day of the eighth lunar month, in September or October, when the moon is at its roundest and brightest. In China, Taiwan and Vietnam families gather, light lanterns and share mooncakes, round pastries whose shape stands for togetherness. Korea celebrates Chuseok, a harvest festival, on the same day, and Japan holds Tsukimi, moon-viewing parties with rice dumplings. A 🌕 in a greeting that night simply means “happy festival, thinking of family”.