how long does blue moon last

A blue moon lasts for the duration of a full moon phase, which is about one night. The term "blue moon" refers to the second full moon occurring in a single calendar month. The Moon completes a full cycle of phases roughly every 29.5 days, so a blue moon happens when two full moons fit within one month, which occurs approximately every 2 to 3 years. The actual visible full moon phase typically lasts for one night, but the Moon appears nearly full for about three days around this time. In summary, the blue moon itself is not a prolonged event; it is simply the second full moon within a month, and the full moon phase lasts about one night, with near-full visibility extending over a few days.