title: Solar eclipse of September 21, 1922
text: # Solar eclipse of September 21, 1922
  
  A total solar eclipse occurred on September 21, 1922. 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 greatest eclipse occurred exactly at perigee.
  
  Totality started in Ethiopia, Italian Somaliland (today's Somalia), and passed British Maldives and Christmas Island in the Straits Settlements (now in Australia) in the Indian Ocean, and Australia. Two large scientific expeditions investigated Einstein's theory of relativity.
  
  ## Related eclipses
  
  ### Solar eclipses 1921–1924
  
  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.
  
  Solar eclipse series sets from 1921–1924 :
  
  | Descending node | Descending node | Ascending node | Ascending node |
  | - | - | - | - |
  | 118 | April 8, 1921 Annular | 123 | October 1, 1921 Total |
  | 128 | March 28, 1922 Annular | 133 | September 21, 1922 Total |
  | 138 | March 17, 1923 Annular | 143 | September 10, 1923 Total |
  | 148 | March 5, 1924 Partial | 153 | August 30, 1924 Partial |
  
  ### Saros 133
  
  Solar Saros 133, repeating every 18 years, 11 days, contains 72 events. The series started with a partial solar eclipse on July 13, 1219. It contains annular eclipses from November 20, 1435, through January 13, 1526, with a hybrid eclipse on January 24, 1544. It has total eclipses from February 3, 1562, through June 21, 2373. The series ends at member 72 as a partial eclipse on September 5, 2499. The longest duration of totality was 6 minutes, 49.97 seconds on August 7, 1850. The total eclipses of this saros series are getting shorter and farther south with each iteration. All eclipses in this series occurs at the Moon’s ascending node.
  
  Series members 30–56 occur between 1742 and 2211 :
  
  | 30 | 31 | 32 |
  | - | - | - |
  | June 3, 1742 | June 13, 1760 | June 24, 1778 |
  | 33 | 34 | 35 |
  | July 4, 1796 | July 17, 1814 | July 27, 1832 |
  | 36 | 37 | 38 |
  | August 7, 1850 | August 18, 1868 | August 29, 1886 |
  | 39 | 40 | 41 |
  | September 9, 1904 | September 21, 1922 | October 1, 1940 |
  | 42 | 43 | 44 |
  | October 12, 1958 | October 23, 1976 | November 3, 1994 |
  | 45 | 46 | 47 |
  | November 13, 2012 | November 25, 2030 | December 5, 2048 |
  | 48 | 49 | 50 |
  | December 17, 2066 | December 27, 2084 | January 8, 2103 |
  | 51 | 52 | 53 |
  | January 19, 2121 | January 30, 2139 | February 9, 2157 |
  | 54 | 55 | 56 |
  | February 21, 2175 | March 3, 2193 | March 15, 2211 |
  