Saros History

The periodicity and recurrence of solar (and lunar) eclipses is governed by the Saros cycle, a period of approximately 6,585.3 days (18 years 11 days 8 hours). When two eclipses are separated by a period of one Saros, they share a very similar geometry. The eclipses occur at the same node with the Moon at nearly the same distance from Earth and at the same time of year. Thus, the Saros is useful for organizing eclipses into families or series. Each series typically lasts 12 to 13 centuries and contains 70 or more eclipses.

The total eclipse of 2001 June 21 is the fifty-seventh member of Saros series 127, as defined by van den Bergh [1955]. All eclipses in the series occur at the Moon's ascending node and the Moon moves southward with each member in the family (i.e. - gamma decreases). The series is a mature one which began with a small partial eclipse at high northern hemisphere latitudes on 0991 Oct 10. After twenty partial eclipses each of increasing magnitude, the first central eclipse occurred on 1352 May 14. The event was a two-minute total eclipse with a path sweeping through Greenland.

The series continued to produce total eclipses of increasing duration as the path of each event shifted further south. The fifth total eclipse is noteworthy because it passed through northern Europe on 1406 June 16. "It was so dark.... that people could not recognize one another.... [they] thought that the end of the world was coming." [Stephenson, 1997]. As subsequent events occurred, the duration continued to grow to a maximum of 5 minutes 40 seconds on 1532 August 30. As a consequence to the path geometry across Earth's surface, the duration of ensuing eclipses began to fall but remained above four minutes.

The paths reversed their southern migration and drifted northward during the 18th and 19th centuries. This effect occurred as a result of Earth's passage from winter solstice through spring equinox whereby the northern hemisphere rapidly tipped towards the Sun. During this period, the duration again approached the five minute mark and exceeded it on 1929 May 9. The umbral path crossed Malaysia and the Philippines. The track of the following eclipse stretched from South America through equatorial Africa on 1947 May 20. The twenty-fifth total eclipse of saros 127 traversed the South Pacific on 1965 May 30. The most recent eclipse occurred on 1983 June 11. Indonesians witnessed a maximum total phase of 5 minutes 11 seconds. After 2001, the following member occurs on 2019 July 02. Its track crosses the Pacific and South America.

The central eclipse phase of saros 127 comes to an end with the total eclipse of 2091 Augus 15. Its landless track falls over open ocean between Australia and Antarctica. The umbral shadow misses Earth's surface during a deep partial eclipse on 2109 August 26. The eclipse magnitude decreases steadily during the next three centuries. Finally, the saros ends with a brief partial eclipse on 2452 March 21. A detailed list of eclipses in Saros series 127 appears in Table 8. A more detailed list, including local circumstances at greatest eclipse, is available.

In summary, Saros series 127 includes 82 eclipses. It begins with 20 partials, followed by 42 total eclipses and ends with 20 more partials. The total duration of Saros 127 is 1460.44 years.


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