- published: 02 Oct 2012
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The saros i/ˈsɛərɒs/ is a period of 223 synodic months (approximately 6585.3213 days, or nearly 18 years 11 days), that can be used to predict eclipses of the Sun and Moon. One saros after an eclipse, the Sun, Earth, and Moon return to approximately the same relative geometry, and a nearly identical eclipse will occur, in what is referred to as an eclipse cycle. A sar is one half of a saros.
A series of eclipses that are separated by one saros is called a saros series.
The earliest discovered historical record of the saros is by the Chaldeans (ancient Babylonian astronomers) in the last several centuries BC. It was later known to Hipparchus, Pliny and Ptolemy, but under different names. The Sumerian/Babylonian word "šár" was one of the ancient Mesopotamian units of measurement and as a number appears to have had a value of 3600. The name "saros" (Greek: σάρος) was first given to the eclipse cycle by Edmond Halley in 1691, who took it from the Suda, a Byzantine lexicon of the 11th century. The information in the Suda in turn was derived directly or otherwise from the Chronicle of Eusebius of Caesarea, which quoted Berossus. Although Halley's naming error was pointed out by Guillaume Le Gentil in 1756, the name continues to be used.
Saros, Şaroş or Sáros may refer to:
Astronomy is a natural science that deals with the study of celestial objects (such as stars, planets, comets, nebulae, star clusters and galaxies) and phenomena that originate outside the atmosphere of Earth (such as cosmic background radiation). It is concerned with the evolution, physics, chemistry, meteorology, and motion of celestial objects, as well as the formation and development of the universe.
Astronomy is one of the oldest sciences. Prehistoric cultures left behind astronomical artifacts such as the Egyptian monuments, Nubian monuments and Stonehenge, and early civilizations such as the Babylonians, Greeks, Chinese, Indians, Iranians and Maya performed methodical observations of the night sky. However, the invention of the telescope was required before astronomy was able to develop into a modern science. Historically, astronomy has included disciplines as diverse as astrometry, celestial navigation, observational astronomy, the making of calendars, and astrology, but professional astronomy is nowadays often considered to be synonymous with astrophysics.