There is a full moon when Earth lies between the Sun and the Moon, so the entire side of the Moon facing us is lit. The full moon rises around sunset, is highest at midnight and sets around sunrise – which is why it shines all night. Below you can see the upcoming full moons, calculated astronomically.
There is a full moon about every 29.5 days – roughly one full moon per month. Sometimes two full moons fall in the same calendar month; the second is popularly called a «blue moon». Between two full moons the Moon passes through new moon and the other moon phases.
When the full moon is low over the horizon it can look unusually large. This is an optical effect known as the «moon illusion». When the Moon is also near Earth in its elliptical orbit, it is called a supermoon, which can appear slightly larger and brighter than usual.
See also the moon today with moonrise and moonset for your location, or the whole month in the moon calendar.
See the upcoming full moons in the list above. The dates are calculated astronomically and updated continuously.
There is a full moon about every 29.5 days, roughly once a month.
A blue moon is when two full moons fall in the same calendar month. It happens because the 29.5-day lunar cycle is slightly shorter than most calendar months.