Solar eclipse of May 21, 2031

This eclipse is a member of a semester series. An eclipse in a semester series of solar eclipses repeats approximately every 177 days and 4 hours (a semester) at alternating nodes of the Moon's orbit.[1]

Note: Partial solar eclipses on January 14, 2029 and July 11, 2029 occur on the previous lunar year eclipse set.

Solar eclipse series sets from 2029–2032
Descending node			Ascending node
118	June 12, 2029 Partial		123	December 5, 2029 Partial
128	June 1, 2030 Annular		133	November 25, 2030 Total
138	May 21, 2031 Annular		143	November 14, 2031 Hybrid
148	May 9, 2032 Annular		153	November 3, 2032 Partial

It is a part of Saros cycle 138, repeating every 18 years, 11 days, containing 70 events. The series started with partial solar eclipse on June 6, 1472. It contains annular eclipses from August 31, 1598 through February 18, 2482 with a hybrid eclipse on March 1, 2500. It has total eclipses from March 12, 2518 through April 3, 2554. The series ends at member 70 as a partial eclipse on July 11, 2716. The longest duration of totality will be only 56 seconds on April 3, 2554.

Series members 25–35 occur between 1901 and 2100:
25	26	27
March 6, 1905	March 17, 1923	March 27, 1941
28	29	30
April 8, 1959	April 18, 1977	April 29, 1995
31	32	33
May 10, 2013	May 21, 2031	May 31, 2049
34	35
June 11, 2067	June 22, 2085

The metonic series repeats eclipses every 19 years (6939.69 days), lasting about 5 cycles. Eclipses occur in nearly the same calendar date. In addition, the octon subseries repeats 1/5 of that or every 3.8 years (1387.94 days). All eclipses in this table occur at the Moon's descending node.[2]

Octon series with 21 events between May 21, 1993 and August 2, 2065
May 20–21	March 8–9	December 25–26	October 13–14	August 1–2
98	100	102	104	106
May 21, 1955	March 9, 1959	December 26, 1962	October 14, 1966	August 2, 1970
108	110	112	114	116
May 21, 1974	March 9, 1978	December 26, 1981	October 14, 1985	August 1, 1989
118	120	122	124	126
May 21, 1993	March 9, 1997	December 25, 2000	October 14, 2004	August 1, 2008
128	130	132	134	136
May 20, 2012	March 9, 2016	December 26, 2019	October 14, 2023	August 2, 2027
138	140	142	144	146
May 21, 2031	March 9, 2035	December 26, 2038	October 14, 2042	August 2, 2046
148	150	152	154	156
May 20, 2050	March 9, 2054	December 26, 2057	October 13, 2061	August 2, 2065
158	160	162	164	166
May 20, 2069	March 8, 2073	December 26, 2076	October 13, 2080	August 1, 2084