Cosmos/Moon/Eclipses: Difference between revisions
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It is said that during a lunar eclipse, the Moon turns red because the only sunlight reaching the Moon passes through Earth’s atmosphere. The more dust or clouds in Earth’s atmosphere during the eclipse, the redder the Moon will appear.
===Saros Cycle===
The Saros Cycle can be used to predict eclipses of the Sun and Moon. The earliest discovered historical record of what is known as the saros is by Chaldean (neo-Babylonian) astronomers in the last several centuries BC. It was later known to Hipparchus, Pliny and Ptolemy.
Every 18 years and 11 days an eclipse occurs at roughly the same position in the zodiac, or to be more precise: 10 1/2 degrees further on (an eclipse occurs when either a new or full moon occurs close to the moon's nodal axis). This is a saros period.
A saros cycle of Solar Eclipses encompasses 70 solar eclipses over a period of 1200 to 1400 years. A saros cycle of Lunar Eclipses encompasses around 45 lunar eclipses over a period of around 800 years.
A series of eclipses that are separated by one saros is called a saros series. It corresponds to:
* 6,585.321347 solar days
* 18.029 years
* 223 synodic months
* 241.999 draconic months
* 18.999 eclipse years (38 eclipse seasons)
* 238.992 anomalistic months
* 241.029 sidereal months
The saros cycle is useful for predicting the times at which nearly identical eclipses will occur.
===Cause of Lunar eclipses according to Zetetic Astronomy <ref name=ZeteticBooks></ref>===
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