Lunar eclipses occur when the Earth comes between the Sun and the Moon, casting its shadow on the Moon during a full moon phase. These events happen during eclipse seasons, which occur approximately every six months and last about 34 days each. When a full moon falls within this period, a lunar eclipse can take place

. In terms of frequency:

• There are typically between 2 to 5 lunar eclipses each calendar year

• The National Weather Service states there can be zero to three lunar eclipses per year visible from any location on Earth

• On average, about three lunar eclipses occur annually worldwide

• The number of eclipses per year varies, with about 70% of years having two lunar eclipses, around 18% having three, and fewer years having four or five

Additionally, total lunar eclipses are less common than partial or penumbral eclipses, making up roughly 29% of all lunar eclipses

. In summary, lunar eclipses happen roughly 2 to 5 times a year globally, with about three being average, occurring during two eclipse seasons spaced about six months apart