A total solar eclipse occurred at the Moon's ascending node of orbit on Tuesday, October 1, 1940, with a magnitude of 1.0645. 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 4 hours before perigee (on October 1, 1940, at 17:00 UTC), the Moon's apparent diameter was larger.
Totality was visible from Colombia, Brazil, Venezuela and South Africa. A partial eclipse was visible for parts of the Caribbean, South America, Central Africa, and Southern Africa.
Observation Members of the Joint Permanent Eclipse Committee of the Royal Society and Royal Astronomical Society made observations in Brazil with interferometers and spectrometers. Teams of the Royal Observatory, Greenwich and Royal Observatory, Cape of Good Hope (now combined into the South African Astronomical Observatory) went to Calvinia, South Africa to study the gravitational lens proposed by the general relativity. Other scientists went to the edge of the path of totality to study the spectral lines of the solar chromosphere. A joint team of the Heliophysical Observatory of the University of Cambridge and the Radcliffe Observatory in Pretoria, South Africa (now combined into the South African Astronomical Observatory) went to Nelspoort to study the extreme ultraviolet spectrum of the chromosphere and corona, and conducted polarization studies of the corona and sky around the sun.
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.
+October 1, 1940 Solar Eclipse Times Event Time (UTC) First Penumbral External Contact 1940 October 1 at 10:08:37.5 UTC First Umbral External Contact 1940 October 1 at 11:03:28.3 UTC First Central Line 1940 October 1 at 11:04:45.3 UTC First Umbral Internal Contact 1940 October 1 at 11:06:02.4 UTC First Penumbral Internal Contact 1940 October 1 at 12:04:11.7 UTC Ecliptic Conjunction 1940 October 1 at 12:41:28.7 UTC Greatest Eclipse 1940 October 1 at 12:44:06.1 UTC Greatest Duration 1940 October 1 at 12:45:03.9 UTC Equatorial Conjunction 1940 October 1 at 12:52:28.6 UTC Last Penumbral Internal Contact 1940 October 1 at 13:23:47.3 UTC Last Umbral Internal Contact 1940 October 1 at 14:22:03.5 UTC Last Central Line 1940 October 1 at 14:23:20.8 UTC Last Umbral External Contact 1940 October 1 at 14:24:38.0 UTC Last Penumbral External Contact 1940 October 1 at 15:19:30.5 UTC
+October 1, 1940 Solar Eclipse Parameters Parameter Value Eclipse Magnitude 1.06446 Eclipse Obscuration 1.13307 Gamma −0.25727 Sun Right Ascension 12h30m03.1s Sun Declination -03°14'42.9" Sun Semi-Diameter 15'58.8" Sun Equatorial Horizontal Parallax 08.8" Moon Right Ascension 12h29m44.0s Moon Declination -03°29'44.3" Moon Semi-Diameter 16'43.8" Moon Equatorial Horizontal Parallax 1°01'24.1" ΔT 24.7 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 October 1940 October 1Ascending node (new moon) October 16Descending node (full moon) Total solar eclipseSolar Saros 133 Penumbral lunar eclipseLunar Saros 145
Related eclipses Eclipses in 1940 A penumbral lunar eclipse on March 23. An annular solar eclipse on April 7. A penumbral lunar eclipse on April 22. A total solar eclipse on October 1. A penumbral lunar eclipse on October 16.
Metonic Preceded by: Solar eclipse of December 13, 1936 Followed by: Solar eclipse of July 20, 1944
Tzolkinex Preceded by: Solar eclipse of August 21, 1933 Followed by: Solar eclipse of November 12, 1947
Half-Saros Preceded by: Lunar eclipse of September 26, 1931 Followed by: Lunar eclipse of October 7, 1949
Tritos Preceded by: Solar eclipse of November 1, 1929 Followed by: Solar eclipse of September 1, 1951
Solar Saros 133 Preceded by: Solar eclipse of September 21, 1922 Followed by: Solar eclipse of October 12, 1958
Inex Preceded by: Solar eclipse of October 22, 1911 Followed by: Solar eclipse of September 11, 1969
Triad Preceded by: Solar eclipse of November 30, 1853 Followed by: Solar eclipse of August 2, 2027
Solar eclipses of 1939–1942
Saros 133
Metonic series
Tritos series
Inex series
Notes
References
External links
https://eap.bl.uk/archive-file/EAP1190-1-7-13