how often blood moon occur

A blood moon, which is a total lunar eclipse where the Moon takes on a reddish color, typically occurs about 2 to 4 times a year, though not all are total eclipses. Total lunar eclipses, which cause the blood moon effect, happen approximately every 2 to 3 years from any given location on Earth. The frequency of lunar eclipses varies due to the Moon’s tilted orbit, preventing an eclipse every full moon. Lunar eclipses can last several hours, with the total phase lasting up to nearly two hours during which the reddish coloration is most visible. Additionally, there is a rare phenomenon called a lunar tetrad, which is a series of four total lunar eclipses occurring about six months apart over two years. These are less common and occur irregularly over centuries. The 21st century will have eight such tetrads, with the next one expected in 2032-2033.