Solar eclipse of July 20, 1925

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]

Solar eclipse series sets from 1924–1928
Ascending node			Descending node
115	July 31, 1924 Partial		120	January 24, 1925 Total
125	July 20, 1925 Annular		130	January 14, 1926 Total
135	July 9, 1926 Annular		140	January 3, 1927 Annular
145	June 29, 1927 Total		150	December 24, 1927 Partial
155	June 17, 1928 Partial

Solar saros 125, repeating every about 18 years and 11 days, contains 73 events. The series started with a partial solar eclipse on February 4, 1060. It has total eclipses from June 13, 1276, to July 16, 1330. It has hybrid eclipses on July 26, 1348, and August 7, 1366, and annular eclipses from August 17, 1384, to August 22, 1979. The series ends at member 73 as a partial eclipse on April 9, 2358. The longest total eclipse occurred on June 25, 1294, at 1 minute and 11 seconds; the longest annular eclipse occurred on July 10, 1907, at 7 minutes and 23 seconds.[2]

Series members 47–58 occur between 1881 and 2100:
47	48	49
June 28, 1889	July 10, 1907	July 20, 1925
50	51	52
August 1, 1943	August 11, 1961	August 22, 1979
53	54	55
September 2, 1997	September 13, 2015	September 23, 2033
56	57	58
October 4, 2051	October 15, 2069	October 26, 2087

This eclipse is a part of the long period inex cycle, repeating at alternating nodes, every 358 synodic months (≈ 10,571.95 days, or 29 years minus 20 days). Their appearance and longitude are irregular due to a lack of synchronization with the anomalistic month (period of perigee). However, groupings of 3 inex cycles (≈ 87 years minus 2 months) comes close (≈ 1,151.02 anomalistic months), so eclipses are similar in these groupings.

Inex series members between 1901 and 2100:
July 20, 1925 (Saros 125)	June 30, 1954 (Saros 126)	June 11, 1983 (Saros 127)
May 20, 2012 (Saros 128)	April 30, 2041 (Saros 129)	April 11, 2070 (Saros 130)
March 21, 2099 (Saros 131)

This eclipse is a part of a tritos cycle, repeating at alternating nodes every 135 synodic months (≈ 3986.63 days, or 11 years minus 1 month). Their appearance and longitude are irregular due to a lack of synchronization with the anomalistic month (period of perigee), but groupings of 3 tritos cycles (≈ 33 years minus 3 months) come close (≈ 434.044 anomalistic months), so eclipses are similar in these groupings.

Series members between 1901 and 2100
September 21, 1903 (Saros 123)	August 21, 1914 (Saros 124)	July 20, 1925 (Saros 125)
June 19, 1936 (Saros 126)	May 20, 1947 (Saros 127)	April 19, 1958 (Saros 128)
March 18, 1969 (Saros 129)	February 16, 1980 (Saros 130)	January 15, 1991 (Saros 131)
December 14, 2001 (Saros 132)	November 13, 2012 (Saros 133)	October 14, 2023 (Saros 134)
September 12, 2034 (Saros 135)	August 12, 2045 (Saros 136)	July 12, 2056 (Saros 137)
June 11, 2067 (Saros 138)	May 11, 2078 (Saros 139)	April 10, 2089 (Saros 140)
March 10, 2100 (Saros 141)

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).

22 eclipse events between December 13, 1898, and July 20, 1982
December 13–14	October 1–2	July 20–21	May 9	February 24–25
111	113	115	117	119
December 13, 1898		July 21, 1906	May 9, 1910	February 25, 1914
121	123	125	127	129
December 14, 1917	October 1, 1921	July 20, 1925	May 9, 1929	February 24, 1933
131	133	135	137	139
December 13, 1936	October 1, 1940	July 20, 1944	May 9, 1948	February 25, 1952
141	143	145	147	149
December 14, 1955	October 2, 1959	July 20, 1963	May 9, 1967	February 25, 1971
151	153	155
December 13, 1974	October 2, 1978	July 20, 1982