# Solar eclipse of September 12, 1931

A partial solar eclipse occurred at the Moon's descending node of orbit on Saturday, September 12, 1931, with a magnitude of 0.0471. 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. 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 of Alaska. This was the 72nd and final event from Solar Saros 114.

## Eclipse details

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.
September 12, 1931 Solar Eclipse Times :
| 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 |
September 12, 1931 Solar Eclipse Parameters :
| 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 |

## Eclipse season

This eclipse is part of an eclipse 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 a fortnight. The first and last eclipse in this sequence is separated by one synodic month.
Eclipse season of September–October 1931 :
| 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 |

## Related eclipses
### Eclipses in 1931

* A total lunar eclipse on April 2.
* A partial solar eclipse on April 18.
* A partial solar eclipse on September 12.
* A total lunar eclipse on September 26.
* A partial solar eclipse on October 11.

### Metonic

* Followed by: Solar eclipse of June 30, 1935

### Tzolkinex

* Preceded by: Solar eclipse of July 31, 1924

### Tritos

* Followed by: Solar eclipse of August 12, 1942

### Solar Saros 114

* Preceded by: Solar eclipse of August 31, 1913

### Triad

* Preceded by: Solar eclipse of November 10, 1844
* Followed by: Solar eclipse of July 13, 2018

### Solar eclipses of 1931–1935

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.
The partial solar eclipses on April 18, 1931 and October 11, 1931 occur in the previous lunar year eclipse set, and the solar eclipses on January 5, 1935 (partial), June 30, 1935 (partial), and December 25, 1935 (annular) occur in the next lunar year eclipse set.
Solar eclipse series sets from 1931 to 1935 :
| Descending node | Descending node | Descending node | Ascending node | Ascending 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 |

### Saros 114

This eclipse is a part of Saros 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 on September 12, 1931. 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 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’s descending node of orbit.
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 |

### Metonic series

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 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 |

### Tritos series

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 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) |

### Inex series

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.
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) | | |