It will be completely visible over Australia and the Pacific, seen rising over Eastern Asia, and setting over North and South America.

Lunar year series (354 days) edit

This eclipse is the third of four lunar year eclipses occurring at the Moon's ascending node.

The lunar year series repeats after 12 lunations or 354 days (Shifting back about 10 days in sequential years). Because of the date shift, the Earth's shadow will be about 11 degrees west in sequential events.

Metonic series edit

First eclipse: May 26, 2002. Second eclipse: May 26, 2021. Third eclipse: May 26, 2040. Fourth eclipse: May 27, 2059.

Half-Saros cycle edit

A lunar eclipse will be preceded and followed by solar eclipses by 9 years and 5.5 days (a half saros).^[1] This lunar eclipse is related to two annular solar eclipses of Solar Saros 138.

Lunar Saros series 131, has 72 lunar eclipses. Solar Saros 138 interleaves with this lunar saros with an event occurring every 9 years 5 days alternating between each saros series.

This eclipse series began in AD 1427 with a partial eclipse at the southern edge of the Earth's shadow when the Moon was close to its descending node. Each successive Saros cycle, the Moon's orbital path is shifted northward with respect to the Earth's shadow, with the first total eclipse occurring in 1950. For the following 252 years, total eclipses occur, with the central eclipse being predicted to occur in 2078. The first partial eclipse after this is predicted to occur in the year 2220, and the final partial eclipse of the series will occur in 2707. The total lifetime of the lunar Saros series 131 is 1280 years. Solar Saros 138 interleaves with this lunar saros with an event occurring every 9 years 5 days alternating between each saros series.

Because of the ⅓ fraction of days in a Saros cycle, the visibility of each eclipse will differ for an observer at a given fixed locale. For the lunar Saros series 131, the first total eclipse of 1950 had its best visibility for viewers in Eastern Europe and the Middle East because mid-eclipse was at 20:44 UT. The following eclipse in the series occurred approximately 8 hours later in the day with mid-eclipse at 4:47 UT, and was best seen from North America and South America. The third total eclipse occurred approximately 8 hours later in the day than the second eclipse with mid-eclipse at 12:43 UT, and had its best visibility for viewers in the Western Pacific, East Asia, Australia and New Zealand. This cycle of visibility repeats from the initiation to termination of the series, with minor variations. Solar Saros 138 interleaves with this lunar saros with an event occurring every 9 years 5 days alternating between each saros series.

Lunar Saros series 131, repeating every 18 years and 11 days, has a total of 72 lunar eclipse events including 57 umbral lunar eclipses (42 partial lunar eclipses and 15 total lunar eclipses). Solar Saros 138 interleaves with this lunar saros with an event occurring every 9 years 5 days alternating between each saros series.

Inex series edit

The inex series repeats eclipses 20 days short of 29 years, repeating on average every 10571.95 days. This period is equal to 358 lunations (synodic months) and 388.5 draconic months. Saros series increment by one on successive Inex events and repeat at alternate ascending and descending lunar nodes.

This period is 383.6734 anomalistic months (the period of the Moon's elliptical orbital precession). Despite the average 0.05 time-of-day shift between subsequent events, the variation of the Moon in its elliptical orbit at each event causes the actual eclipse time to vary significantly. It is a part of Lunar Inex series 39.

All events in this series listed below and more are total lunar eclipses.

• List of lunar eclipses and List of 21st-century lunar eclipses

• NASA: Lunar Eclipses: Past and Future
  • 2040 May 26 chart: Eclipse Predictions by Fred Espenak, NASA/GSFC
  • Index to Five Millennium Catalog of Lunar Eclipses, -1999 to +3000 (2000 BCE to 3000 CE)
    • Eclipses: 2001 to 2100^{[dead link]}

• Bao-Lin Liu, Canon of Lunar Eclipses 1500 B.C.-A.D. 3000, 1992