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.
A U.S. expedition was sent under the leadership of Lyman J. Briggs. It was sponsored by the National Geographic Society and the U.S. Army Air Force. The base camp was set up on a plateau around 400 miles north of Rio de Janeiro.
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.
+May 20, 1947 Solar Eclipse Times Event Time (UTC) First Penumbral External Contact 1947 May 20 at 11:11:14.5 UTC First Umbral External Contact 1947 May 20 at 12:08:46.7 UTC First Central Line 1947 May 20 at 12:09:53.9 UTC First Umbral Internal Contact 1947 May 20 at 12:11:01.1 UTC First Penumbral Internal Contact 1947 May 20 at 13:16:38.2 UTC Equatorial Conjunction 1947 May 20 at 13:35:31.5 UTC Ecliptic Conjunction 1947 May 20 at 13:44:07.5 UTC Greatest Eclipse 1947 May 20 at 13:47:47.0 UTC Greatest Duration 1947 May 20 at 13:54:23.9 UTC Last Penumbral Internal Contact 1947 May 20 at 14:19:13.8 UTC Last Umbral Internal Contact 1947 May 20 at 15:24:38.7 UTC Last Central Line 1947 May 20 at 15:25:47.7 UTC Last Umbral External Contact 1947 May 20 at 15:26:56.7 UTC Last Penumbral External Contact 1947 May 20 at 16:24:20.8 UTC
+May 20, 1947 Solar Eclipse Parameters Parameter Value Eclipse Magnitude 1.05567 Eclipse Obscuration 1.11445 Gamma −0.35279 Sun Right Ascension 03h45m52.5s Sun Declination +19°52'36.9" Sun Semi-Diameter 15'48.2" Sun Equatorial Horizontal Parallax 08.7" Moon Right Ascension 03h46m20.8s Moon Declination +19°32'28.8" Moon Semi-Diameter 16'25.3" Moon Equatorial Horizontal Parallax 1°00'16.3" ΔT 28.0 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.
+ Eclipse season of May–June 1947 May 20Ascending node (new moon) June 3Descending node (full moon) Total solar eclipseSolar Saros 127 Partial lunar eclipseLunar Saros 139
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
Saros 127
Metonic series
Tritos series
Inex series
References
External links
Russia expedition for solar eclipse of May 20, 1947