Solar eclipse of August 21, 1914

A total solar eclipse occurred on August 21, 1914. 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. The totality of this eclipse was visible from northern Canada, Greenland, Norway, Sweden, Russian Empire (the parts now belonging to Åland, Finland, Estonia, Latvia, Lithuania, Belarus, Ukraine and Russia, including cities of Riga, Minsk, Kiev and northeastern part of Vilnius), Ottoman Empire (the parts now belonging to Turkey, northeastern tip of Syria and northern Iraq), Persia and British Raj (the parts now belonging to Pakistan and western tip of India). It was the first of four total solar eclipses that would be seen from Sweden during the next 40 years. This total solar eclipse occurred in the same calendar date as 2017, but at the opposite node. The moon was just 2.7 days before perigee, making it fairly large.

Solar eclipse of August 21, 1914
SE1914Aug21T.png
Map
Type of eclipse
NatureTotal
Gamma0.7655
Magnitude1.0328
Maximum eclipse
Duration134 sec (2 m 14 s)
Coordinates54°30′N 27°06′E / 54.5°N 27.1°E / 54.5; 27.1
Max. width of band170 km (110 mi)
Times (UTC)
Greatest eclipse12:34:27
References
Saros124 (49 of 73)
Catalog # (SE5000)9314

A number of observatories sent expeditions to Russia to observe the eclipse including those from Argentina, England, Germany, Russia, and the United States. The expeditions led by Charles Dillon Perrine of the Argentine National Observatory, Erwin Finlay-Freundlich of the Berlin-Babelsberg Observatory, Germany, and William W. Campbell of the Lick Observatory, California, included in their programs the second attempt to verify the general relativity theory of Albert Einstein. (Perrine had made the first attempt at the 1912 solar eclipse in Brazil.[1]) However, World War I broke out and Freundlich and his equipment were interned in Russia, unable to carry out the necessary measurements. C. D. Perrine and W. W. Campbell, from neutral countries, Argentina and the United States, were permitted to continue with their plans, but clouds obscured the eclipse.[1][2] Perrine was able to obtain one photograph of the eclipse but the thin cloud cover was enough to obscure star locations necessary to test Einstein's theory.[3]

Related eclipsesEdit

Solar eclipses of 1913–1917Edit

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.[4]

Solar eclipse series sets from 1913–1917
Descending node   Ascending node
114 August 31, 1913
 
Partial
119 February 25, 1914
 
Annular
124 August 21, 1914
 
Total
129 February 14, 1915
 
Annular
134 August 10, 1915
 
Annular
139 February 3, 1916
 
Total
144 July 30, 1916
 
Annular
149 January 23, 1917
 
Partial
154 July 19, 1917
 
Partial

Saros 124Edit

Solar saros 124, repeating every about 18 years and 11 days, contains 73 events. The series started with partial solar eclipse on March 6, 1049. It contains total eclipses from June 12, 1211, to September 22, 1968, and a hybrid solar eclipse on October 3, 1986. The series ends at member 73 as a partial eclipse on May 11, 2347. The longest total eclipse occurred on May 3, 1734, at 5 minutes and 46 seconds.[5]

Series members 43–59 occur between 1801 and 2100:
43 44 45
 
June 16, 1806
 
June 26, 1824
 
July 8, 1842
46 47 48
 
July 18, 1860
 
July 29, 1878
 
August 9, 1896
49 50 51
 
August 21, 1914
 
August 31, 1932
 
September 12, 1950
52 53 54
 
September 22, 1968
 
October 3, 1986
 
October 14, 2004
55 56 57
 
October 25, 2022
 
November 4, 2040
 
November 16, 2058
58 59
 
November 26, 2076
 
December 7, 2094

Tritos seriesEdit

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.

ReferencesEdit

  1. ^ a b Perrine, Charles D. (1923). "Contribution to the history of attempts to test the theory of relativity by means of astronomical observations". Astronomische Nachrichten. 219 (17): 281–284. doi:10.1002/asna.19232191706.
  2. ^ Campbell, W.W.; Curtis, H.D. (1914). "The Lick Observatory-Crocker Eclipse Expedition to Brovarý, Russia". Publications of the Astronomical Society of the Pacific. 26 (156): 225–237. doi:10.1086/122351.
  3. ^ Minniti, Edgardo; Paolantonio, Santiago (2013). "Attempts to prove Einstein's Theory of Relativity" (PDF). Córdoba Estelar. Translated by Cuestas, A.D.; Scorians, E.E.; Valotta, M.E. Córdoba, Argentina: Universidad Nacional de Córdoba. pp. 402–425.
  4. ^ van Gent, R.H. "Solar- and Lunar-Eclipse Predictions from Antiquity to the Present". A Catalogue of Eclipse Cycles. Utrecht University. Retrieved 6 October 2018.
  5. ^ Saros Series Catalog of Solar Eclipses NASA Eclipse Web Site.