Solar eclipse of September 23, 2071

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]

120	April 21, 2069 Partial	125	October 15, 2069 Partial
130	April 11, 2070 Total	135	October 4, 2070 Annular
140	March 31, 2071 Annular	145	September 23, 2071 Total
150	March 19, 2072 Partial	155	September 12, 2072 Total

This solar eclipse is a part of Saros cycle 145, repeating every 18 years, 11 days, 8 hours, containing 77 events. The series started with a partial solar eclipse on January 4, 1639, and reached a first annular eclipse on June 6, 1891. It was a hybrid event on June 17, 1909, and total eclipses from June 29, 1927, through September 9, 2648. The series ends at member 77 as a partial eclipse on April 17, 3009. The longest eclipse will occur on June 25, 2522, with a maximum duration of totality of 7 minutes, 12 seconds. All eclipses in this series occurs at the Moon’s ascending node.

Series members 10–32 occur between 1801 and 2359
10	11	12
April 13, 1801	April 24, 1819	May 4, 1837
13	14	15
May 16, 1855	May 26, 1873	June 6, 1891
16	17	18
June 17, 1909	June 29, 1927	July 9, 1945
19	20	21
July 20, 1963	July 31, 1981	August 11, 1999
22	23	24
August 21, 2017	September 2, 2035	September 12, 2053
25	26	27
September 23, 2071	October 4, 2089	October 16, 2107
28	29	30
October 26, 2125	November 7, 2143	November 17, 2161
31	32	33
November 28, 2179	December 9, 2197	December 21, 2215
34	35	36
December 31, 2233	January 12, 2252	January 22, 2270
37	38	39
February 2, 2288	February 14, 2306	February 25, 2324
40
March 8, 2342

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:
January 3, 1927 (Saros 140)	December 14, 1955 (Saros 141)	November 22, 1984 (Saros 142)
November 3, 2013 (Saros 143)	October 14, 2042 (Saros 144)	September 23, 2071 (Saros 145)
September 4, 2100 (Saros 146)

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 ascending node.

21 eclipse events, progressing from south to north between July 13, 2018 and July 12, 2094
July 12–13	April 30-May 1	February 16–17	December 5–6	September 22–23
117	119	121	123	125
July 13, 2018	April 30, 2022	February 17, 2026	December 5, 2029	September 23, 2033
127	129	131	133	135
July 13, 2037	April 30, 2041	February 16, 2045	December 5, 2048	September 22, 2052
137	139	141	143	145
July 12, 2056	April 30, 2060	February 17, 2064	December 6, 2067	September 23, 2071
147	149	151	153	155
July 13, 2075	May 1, 2079	February 16, 2083	December 6, 2086	September 23, 2090
157
July 12, 2094