Supermoon

In short, Earth, Moon and Sun are all in a line, with Moon in its nearest approach to Earth.He came up with the name while reading Strategic Role Of Perigean Spring Tides in Nautical History and Coastal Flooding published in 1976 by Fergus Wood, a hydrologist with NOAA.

[6][7] Nolle explained in 2011 that he based calculations on 90% of the difference in lunar apsis extremes for the solar year.

[13] Wood used the definition of a full or new moon occurring within 24 hours of perigee and also used the label perigee-syzygy.

[7] Wood also coined the less used term proxigee where perigee and the full or new moon are separated by 10 hours or less.

[14] Of the possible 12 or 13 full (or new) moons each year, usually three or four may be classified as supermoons, as commonly defined.

[16] The oscillating nature of the distance to the full or new moon is due to the difference between the synodic and anomalistic months.

A full moon at perigee appears roughly 14% larger in diameter than at apogee.

[18] 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 apogee.

[2][21][22][23] Despite lack of scientific evidence, there has been media speculation that natural disasters, such as the 2011 Tōhoku earthquake and tsunami and the 2004 Indian Ocean earthquake and tsunami, are causally linked with the 1–2-week period surrounding a supermoon.

[24] A large, 7.5 magnitude earthquake centred 15 km north-east of Culverden, New Zealand at 00:03 NZDT on November 14, 2016, also coincided with a supermoon.

[28] and that during lunar perigee, the tidal force is somewhat stronger,[29] resulting in perigean spring tides.

However, even at its most powerful, this force is still relatively weak,[30] causing tidal differences of inches at most.

[31][b] Total lunar eclipses which fall on supermoon and micromoon days are relatively rare.

This phenomenon is often called a blood moon because of its striking red or orange color.

This unique alignment creates a visually impressive and rare sight that has inspired folklore and intrigue for centuries.

Super Blood Moons are relatively infrequent, occurring about once every few years, making them a notable event for astronomers and skywatchers alike.

Annular solar eclipses occur when the Moon's apparent diameter is smaller than the Sun's.