saros
/ˈsɛrɑs/
noun
- A period of about 18 years and 11 days after which the sun, moon, and Earth return to nearly the same relative positions, causing a cycle of eclipses.
- A saros cycle lasts approximately 6,585 days.
- The next total solar eclipse in this saros series will occur in 2034.
- Ancient astronomers used the saros to predict eclipses.