Solar eclipse of May 20, 1947

A total solar eclipse occurred at the Moon's ascending node of orbit on Tuesday, May 20, 1947, with a magnitude of 1.0557. 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 total solar eclipse occurs when the Moon's apparent diameter is larger than the Sun's, blocking all direct sunlight, turning day into darkness. Totality occurs in a narrow path across Earth's surface, with the partial solar eclipse visible over a surrounding region thousands of kilometres wide. Occurring about 1.8 days before perigee (on May 22, 1947, at 9:10 UTC), the Moon's apparent diameter was larger.

Totality was visible from Chile including the capital city Santiago, Argentina, Paraguay, Brazil, Liberia, French West Africa (the parts now belonging to Ivory Coast and Benin), British Gold Coast (today's Ghana) including capital Accra, French Togoland (today's Togo) including capital Lomé, British Nigeria (today's Nigeria) including capital Lagos, French Cameroons (now belonging to Cameroon), French Equatorial Africa (the parts now belonging to Central African Republic and R. Congo), Belgian Congo (today's DR Congo), British Uganda (today's Uganda), British Tanganyika (now belonging to Tanzania), and British Kenya (today's Kenya). The southern part of Aconcagua, the highest mountain outside Asia, and Iguazu Falls, one of the largest waterfalls systems in the world, lay in the path of totality. A partial eclipse was visible for most of South America and Africa.

Observations

The Royal Astronomical Society of Canada sent a team to Araxa, Brazil. On the morning of the eclipse day, the sky was covered with clouds. Although a slight part of sunlight was seen through the gaps in the clouds around the first contact (the beginning of the partial phase), the weather did not improve after that. The eclipse ended at noon, and the sky began to clear up in the afternoon. The team documented changes in winds and luminance of the sky. Australian radio astronomers originally planned to go to Brazil to make radio observations to promote the development of radio astronomy in Australia. However, the shipping of the equipments could only be made via London at that time, and it was not made before the eclipse in the end, so the plan was not successful. Another team from the Soviet Union successfully made radio observations in Brazil.

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.

Related eclipses

Eclipses in 1947

• A total solar eclipse on May 20.
• A partial lunar eclipse on June 3.
• An annular solar eclipse on November 12.
• A penumbral lunar eclipse on November 28.

Metonic

• Preceded by: Solar eclipse of August 1, 1943
• Followed by: Solar eclipse of March 7, 1951

Tzolkinex

• Preceded by: Solar eclipse of April 7, 1940
• Followed by: Solar eclipse of June 30, 1954

Half-Saros

• Preceded by: Lunar eclipse of May 14, 1938
• Followed by: Lunar eclipse of May 24, 1956

Tritos

• Preceded by: Solar eclipse of June 19, 1936
• Followed by: Solar eclipse of April 19, 1958

Solar Saros 127

• Preceded by: Solar eclipse of May 9, 1929
• Followed by: Solar eclipse of May 30, 1965

Inex

• Preceded by: Solar eclipse of June 8, 1918
• Followed by: Solar eclipse of April 29, 1976

Triad

• Preceded by: Solar eclipse of July 18, 1860
• Followed by: Solar eclipse of March 20, 2034

Solar eclipses of 1946–1949

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 January 3, 1946 and June 29, 1946 occur in the previous lunar year eclipse set.

Saros 127

This eclipse is a part of Saros series 127, repeating every 18 years, 11 days, and containing 82 events. The series started with a partial solar eclipse on October 10, 991 AD. It contains total eclipses from May 14, 1352 through August 15, 2091. There are no annular or hybrid eclipses in this set. The series ends at member 82 as a partial eclipse on March 21, 2452. 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 31 at 5 minutes, 40 seconds on August 30, 1532. All eclipses in this series occur at the Moon’s ascending 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 ascending 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
• August 10, 2009, at the Wayback Machine