is the point at which the Moon is closest in its orbit to the Earth, and syzygy is when the Earth, the Moon and the Sun are aligned, which happens at every full or new moon. Astrophysicist Fred Espenak uses Nolle's definition but preferring the label of full Moon at perigee on full moons occurring "within 90% of its closest approach to Earth in a given orbit" over Nolle's calculations based on the closest of all orbits during the solar year. Wood used the definition of a full or new moon occurring within 24 hours of perigee and also used the label perigee-syzygy. Other definitions Sky and Telescope magazine chose a definition of . TimeandDate.com prefers a definition of . EarthSky uses Nolle's definition comparing their calculations to tables published by Nolle in 2000. Wood also coined the less used term proxigee where perigee and the full or new moon are separated by 10 hours or less. Occurrence Of the possible 12 or 13 full (or new) moons each year, usually three or four may be classified as supermoons, as commonly defined. The most recent full supermoon occurred on August 12, 2022, and the next one will be on July 3, 2023. The supermoon of November 14, 2016, was the closest full occurrence since January 26, 1948, and will not be surpassed until November 25, 2034. The closest full supermoon of the 21st century will occur on December 6, 2052. The oscillating nature of the distance to the full or new moon is due to the difference between the synodic and anomalistic months. The period of this oscillation is about 14 synodic months, which is close to 15 anomalistic months. So every 14 lunations there is a Full Moon nearest to perigee. Occasionally, a supermoon coincides with a total lunar eclipse. The most recent occurrence of this by any definition was in May 2022, and the next occurrence will be in October 2032. Appearance A full moon at perigee appears roughly 14% larger in diameter than at apogee. Many observers insist that the moon looks bigger to them. This is likely due to observations shortly after sunset when the moon is near the horizon and the moon illusion is at its most apparent. While the moon's surface luminance remains the same, because it is closer to the earth the illuminance is about 30% brighter than at its farthest point, or