An interval of 18 years 11.3 days (or 10.3 days, depending on the number of intervening leap years), equivalent to 223 lunations, following which the Sun, Moon, and Earth return to almost the same alignment. Solar eclipses recur one saros apart, but at different geographical locations. One saros period is almost the same as 19 eclipse years; the slight discrepancy leads to eclipses in a saros series gradually occurring further north or south until after some 70 eclipses (1262 years) their path no longer falls on the Earth’s surface.