|From "Moon Child" (Random House/Tricycle Books)|
"Because the orbit of the moon is not a perfect circle, the moon is sometimes closer to the Earth than at other times during its orbit," said Noah Petro, deputy project scientist for the Lunar. A lunar eclipse typically puts on an even greater show. For more than an hour, Earth’s shadow swallows up the moon as the planet comes between the sun and the moon. Lunar eclipses typically occur at least twice a year, and 228 will occur in the 21st century alone. While people such as the Incans and Mesopotamians historically viewed lunar eclipses as random and frightening occurrences, they’re actually quite predictable.
Scientists at Goddard have predicted eclipses a thousand years into the future. Petro said it’s just a matter of knowing where Earth, the sun and the moon are at a given point in time.
See more at: