| Partial eclipse | |
 Map | |
| Gamma | 1.506 |
|---|---|
| Magnitude | 0.0471 |
| Maximum eclipse | |
| Coordinates | 61°12′N152°48′W / 61.2°N 152.8°W /61.2; -152.8 |
| Times (UTC) | |
| Greatest eclipse | 4:41:25 |
| References | |
| Saros | 114 (72 of 72) |
| Catalog # (SE5000) | 9355 |
A partialsolar eclipse occurred at the Moon'sdescending node of orbit on Saturday, September 12, 1931,[1] with amagnitude of 0.0471. Asolar eclipse occurs when theMoon passes betweenEarth and theSun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. A partial solar eclipse occurs in the polar regions of the Earth when the center of the Moon's shadow misses the Earth.
A partial eclipse was visible for parts ofAlaska. This was the 72nd and final event fromSolar Saros 114.
Shown below are two tables displaying details about this particular solar eclipse. The first table outlines times at which the Moon's penumbra or umbra attains the specific parameter, and the second table describes various other parameters pertaining to this eclipse.[2]
| Event | Time (UTC) |
|---|---|
| Equatorial Conjunction | 1931 September 12 at 03:17:27.4 UTC |
| First Penumbral External Contact | 1931 September 12 at 04:13:32.8 UTC |
| Ecliptic Conjunction | 1931 September 12 at 04:26:43.8 UTC |
| Greatest Eclipse | 1931 September 12 at 04:41:24.8 UTC |
| Last Penumbral External Contact | 1931 September 12 at 05:09:49.8 UTC |
| Parameter | Value |
|---|---|
| Eclipse Magnitude | 0.04713 |
| Eclipse Obscuration | 0.01234 |
| Gamma | 1.50603 |
| Sun Right Ascension | 11h17m33.8s |
| Sun Declination | +04°33'58.3" |
| Sun Semi-Diameter | 15'53.5" |
| Sun Equatorial Horizontal Parallax | 08.7" |
| Moon Right Ascension | 11h20m30.0s |
| Moon Declination | +05°54'53.5" |
| Moon Semi-Diameter | 16'41.5" |
| Moon Equatorial Horizontal Parallax | 1°01'15.6" |
| ΔT | 23.9 s |
This eclipse is part of aneclipse season, a period, roughly every six months, when eclipses occur. Only two (or occasionally three) eclipse seasons occur each year, and each season lasts about 35 days and repeats just short of six months (173 days) later; thus two full eclipse seasons always occur each year. Either two or three eclipses happen each eclipse season. In the sequence below, each eclipse is separated by afortnight. The first and last eclipse in this sequence is separated by onesynodic month.
| September 12 Descending node (new moon) | September 26 Ascending node (full moon) | October 11 Descending node (new moon) |
|---|---|---|
|  |  |
| Partial solar eclipse Solar Saros 114 | Total lunar eclipse Lunar Saros 126 | Partial solar eclipse Solar Saros 152 |
This eclipse is a member of asemester series. An eclipse in a semester series of solar eclipses repeats approximately every 177 days and 4 hours (a semester) at alternatingnodes of the Moon's orbit.[3]
The partial solar eclipses onApril 18, 1931 andOctober 11, 1931 occur in the previous lunar year eclipse set, and the solar eclipses onJanuary 5, 1935 (partial),June 30, 1935 (partial), andDecember 25, 1935 (annular) occur in the next lunar year eclipse set.
| Solar eclipse series sets from 1931 to 1935 | ||||||
|---|---|---|---|---|---|---|
| Descending node | Ascending node | |||||
| Saros | Map | Gamma | Saros | Map | Gamma | |
| 114 | September 12, 1931 Partial | 1.506 | 119 | March 7, 1932 Annular | −0.9673 | |
| 124 | August 31, 1932 Total | 0.8307 | 129 | February 24, 1933 Annular | −0.2191 | |
| 134 | August 21, 1933 Annular | 0.0869 | 139 | February 14, 1934 Total | 0.4868 | |
| 144 | August 10, 1934 Annular | −0.689 | 149 | February 3, 1935 Partial | 1.1438 | |
| 154 | July 30, 1935 Partial | −1.4259 | ||||
This eclipse is a part ofSaros series 114, repeating every 18 years, 11 days, and containing 72 events. The series started with a partial solar eclipse on July 23, 651 AD. It contains annular eclipses from February 3, 976 AD through June 11, 1192; hybrid eclipses from June 22, 1210 through December 1, 1480; and total eclipses from December 13, 1498 through June 15, 1787. The series ends at member 72 as a partial eclipse onSeptember 12, 1931. Its eclipses are tabulated in three columns; every third eclipse in the same column is oneexeligmos apart, so they all cast shadows over approximately the same parts of the Earth.
The longest duration of annularity was produced by member 20 at 4 minutes, 33 seconds on February 13, 994 AD, and the longest duration of totality was produced by member 59 at 4 minutes, 18 seconds on April 21, 1697. All eclipses in this series occur at the Moon’sdescending node of orbit.[4]
| Series members 65–72 occur between 1801 and 1931: | ||
|---|---|---|
| 65 | 66 | 67 |
 June 26, 1805 |  July 8, 1823 |  July 18, 1841 |
| 68 | 69 | 70 |
 July 29, 1859 |  August 9, 1877 |  August 20, 1895 |
| 71 | 72 | |
 August 31, 1913 | September 12, 1931 | |
Themetonic 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.
| 22 eclipse events between September 12, 1931 and July 1, 2011 | ||||
|---|---|---|---|---|
| September 11–12 | June 30–July 1 | April 17–19 | February 4–5 | November 22–23 |
| 114 | 116 | 118 | 120 | 122 |
September 12, 1931 |  June 30, 1935 |  April 19, 1939 |  February 4, 1943 |  November 23, 1946 |
| 124 | 126 | 128 | 130 | 132 |
 September 12, 1950 |  June 30, 1954 |  April 19, 1958 |  February 5, 1962 |  November 23, 1965 |
| 134 | 136 | 138 | 140 | 142 |
 September 11, 1969 |  June 30, 1973 |  April 18, 1977 |  February 4, 1981 |  November 22, 1984 |
| 144 | 146 | 148 | 150 | 152 |
 September 11, 1988 |  June 30, 1992 |  April 17, 1996 |  February 5, 2000 |  November 23, 2003 |
| 154 | 156 | |||
 September 11, 2007 |  July 1, 2011 | |||
This eclipse is a part of atritos cycle, repeating at alternating nodes every 135synodic months (≈ 3986.63 days, or 11 years minus 1 month). Their appearance and longitude are irregular due to a lack of synchronization with theanomalistic 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 1866 and 2200 | ||||
|---|---|---|---|---|
 March 16, 1866 (Saros 108) |  December 13, 1898 (Saros 111) | |||
September 12, 1931 (Saros 114) |  August 12, 1942 (Saros 115) |  July 11, 1953 (Saros 116) |  June 10, 1964 (Saros 117) | |
 May 11, 1975 (Saros 118) |  April 9, 1986 (Saros 119) |  March 9, 1997 (Saros 120) |  February 7, 2008 (Saros 121) |  January 6, 2019 (Saros 122) |
 December 5, 2029 (Saros 123) |  November 4, 2040 (Saros 124) |  October 4, 2051 (Saros 125) |  September 3, 2062 (Saros 126) |  August 3, 2073 (Saros 127) |
 July 3, 2084 (Saros 128) |  June 2, 2095 (Saros 129) |  May 3, 2106 (Saros 130) |  April 2, 2117 (Saros 131) |  March 1, 2128 (Saros 132) |
 January 30, 2139 (Saros 133) |  December 30, 2149 (Saros 134) |  November 27, 2160 (Saros 135) |  October 29, 2171 (Saros 136) |  September 27, 2182 (Saros 137) |
 August 26, 2193 (Saros 138) | ||||
This eclipse is a part of the long periodinex cycle, repeating at alternating nodes, every 358synodic months (≈ 10,571.95 days, or 29 years minus 20 days). Their appearance and longitude are irregular due to a lack of synchronization with theanomalistic 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.
| Series members between 1844 and 2200 | ||
|---|---|---|
 November 10, 1844 (Saros 111) | ||
September 12, 1931 (Saros 114) | ||
 July 13, 2018 (Saros 117) |  June 23, 2047 (Saros 118) |  June 1, 2076 (Saros 119) |
 May 14, 2105 (Saros 120) |  April 24, 2134 (Saros 121) |  April 3, 2163 (Saros 122) |
 March 13, 2192 (Saros 123) | ||
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