Solar eclipse of September 9, 1904

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 1902–1907
Descending node			Ascending node
108	April 8, 1902 Partial		113	October 1, 1902
118	March 29, 1903 Annular		123	September 21, 1903 Total
128	March 17, 1904 Annular		133	September 9, 1904 Total
138	March 6, 1905 Annular		143	August 30, 1905 Total
148	February 23, 1906 Partial		153	August 20, 1906 Partial

Solar Saros 133, repeating every 18 years, 11 days, contains 72 events. The series started with a partial solar eclipse on July 13, 1219. It contains annular eclipses from November 20, 1435, through January 13, 1526, with a hybrid eclipse on January 24, 1544. It has total eclipses from February 3, 1562, through June 21, 2373. The series ends at member 72 as a partial eclipse on September 5, 2499. The longest duration of totality was 6 minutes, 49.97 seconds on August 7, 1850.[2] The total eclipses of this saros series are getting shorter and farther south with each iteration. All eclipses in this series occurs at the Moon’s ascending node.

Series members 30–56 occur between 1742 and 2211
30	31	32
June 3, 1742	June 13, 1760	June 24, 1778
33	34	35
July 4, 1796	July 17, 1814	July 27, 1832
36	37	38
August 7, 1850	August 18, 1868	August 29, 1886
39	40	41
September 9, 1904	September 21, 1922	October 1, 1940
42	43	44
October 12, 1958	October 23, 1976	November 3, 1994
45	46	47
November 13, 2012	November 25, 2030	December 5, 2048
48	49	50
December 17, 2066	December 27, 2084	January 8, 2103
51	52	53
January 19, 2121	January 30, 2139	February 9, 2157
54	55	56
February 21, 2175	March 3, 2193	March 15, 2211

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. In the 18th century:

• Solar Saros 127: Total Solar Eclipse of 1731 Jan 08
• Solar Saros 128: Annular Solar Eclipse of 1759 Dec 19
• Solar Saros 129: Annular Solar Eclipse of 1788 Nov 27

Inex series members between 1801 and 2200:
Near lunar perigee	After lunar apogee Before lunar perigee	Before lunar apogee After lunar perigee
November 9, 1817 (Saros 130)	October 20, 1846 (Saros 131)	September 29, 1875 (Saros 132)
September 9, 1904 (Saros 133)	August 21, 1933 (Saros 134)	July 31, 1962 (Saros 135)
July 11, 1991 (Saros 136)	June 21, 2020 (Saros 137)	May 31, 2049 (Saros 138)
May 11, 2078 (Saros 139)	April 23, 2107 (Saros 140)	April 1, 2136 (Saros 141)
March 12, 2165 (Saros 142)	February 21, 2194 (Saros 143)

In the 23rd century:

• Solar Saros 144: Annular Solar Eclipse of 2223 Feb 01
• Solar Saros 145: Total Solar Eclipse of 2252 Jan 12
• Solar Saros 146: Annular Solar Eclipse of 2280 Dec 22

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 9, 1904 (Saros 133)	August 10, 1915 (Saros 134)	July 9, 1926 (Saros 135)
June 8, 1937 (Saros 136)	May 9, 1948 (Saros 137)	April 8, 1959 (Saros 138)
March 7, 1970 (Saros 139)	February 4, 1981 (Saros 140)	January 4, 1992 (Saros 141)
December 4, 2002 (Saros 142)	November 3, 2013 (Saros 143)	October 2, 2024 (Saros 144)
September 2, 2035 (Saros 145)	August 2, 2046 (Saros 146)	July 1, 2057 (Saros 147)
May 31, 2068 (Saros 148)	May 1, 2079 (Saros 149)	March 31, 2090 (Saros 150)