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.

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.

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.

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.

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.

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.

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.

External links

• Eclipse Predictions by Fred Espenak, NASA/GSFC