Solar eclipse of December 14, 1917

Solar eclipse of December 14, 1917
Solar eclipse of December 14, 1917
	Map
Type of eclipse
Nature	Annular
Gamma	−0.9157
Magnitude	0.9791
Maximum eclipse
Duration	77 s (1 min 17 s)
Coordinates	88°00′S 124°48′E / 88°S 124.8°E
Max. width of band	189 km (117 mi)
Times (UTC)
Greatest eclipse	9:27:20
References
Saros	121 (55 of 71)
Catalog # (SE5000)	9323

An annular solar eclipse occurred at the Moon's ascending node of orbit on Friday, December 14, 1917, with a magnitude of 0.9791. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. An annular solar eclipse occurs when the Moon's apparent diameter is smaller than the Sun's, blocking most of the Sun's light and causing the Sun to look like an annulus (ring). An annular eclipse appears as a partial eclipse over a region of the Earth thousands of kilometres wide.

This was the last of four solar eclipses in 1917, with the others occurring on January 23, June 19 and July 19.

This annular eclipse is notable in that the path of annularity passed over the South Pole.

Related eclipses[edit]

Solar eclipses of 1916–1920[edit]

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]

The solar eclipses on February 3, 1916 (total), July 30, 1916 (annular), January 23, 1917 (partial), and July 19, 1917 (partial) occur in the previous lunar year eclipse set.

Solar eclipse series sets from 1916 to 1920
Ascending node			Descending node
Saros	Map	Gamma	Saros	Map	Gamma
111	December 24, 1916 Partial	−1.5321	116	June 19, 1917 Partial	1.2857
121	December 14, 1917 Annular	−0.9157	126	June 8, 1918 Total	0.4658
131	December 3, 1918 Annular	−0.2387	136 Totality in Príncipe	May 29, 1919 Total	−0.2955
141	November 22, 1919 Annular	0.4549	146	May 18, 1920 Partial	−1.0239
151	November 10, 1920 Partial	1.1287

Saros 121[edit]

This eclipse is a part of Saros series 121, repeating every 18 years, 11 days, and containing 71 events. The series started with a partial solar eclipse on April 25, 944 AD. It contains total eclipses from July 10, 1070 through October 9, 1809; hybrid eclipses on October 20, 1827 and October 30, 1845; and annular eclipses from November 11, 1863 through February 28, 2044. The series ends at member 71 as a partial eclipse on June 7, 2206. Its eclipses are tabulated in three columns; every third eclipse in the same column is one exeligmos apart, so they all cast shadows over approximately the same parts of the Earth.

The longest duration of totality was produced by member 39 at 6 minutes, 20 seconds on June 21, 1629, and the longest duration of annularity will be produced by member 62 at 2 minutes, 27 seconds on February 28, 2044. All eclipses in this series occur at the Moon’s ascending node of orbit.^[2]

Series members 49–70 occur between 1801 and 2200:
49	50	51
October 9, 1809	October 20, 1827	October 30, 1845
52	53	54
November 11, 1863	November 21, 1881	December 3, 1899
55	56	57
December 14, 1917	December 25, 1935	January 5, 1954
58	59	60
January 16, 1972	January 26, 1990	February 7, 2008
61	62	63
February 17, 2026	February 28, 2044	March 11, 2062
64	65	66
March 21, 2080	April 1, 2098	April 13, 2116
67	68	69
April 24, 2134	May 4, 2152	May 16, 2170
70
May 26, 2188

Metonic series[edit]

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