An extraordinary series of lunar eclipses is about to begin. The action starts on April 15th when the full Moon passes through the amber shadow of Earth, producing a midnight eclipse visible across North America. So begins a lunar eclipse tetrad—a series of 4 consecutive total eclipses occurring at approximately six month intervals.

The total eclipse of April 15, 2014, will be followed by another on Oct. 8, 2014, and another on April 4, 2015, and another on Sept. 28 2015.

The most recent tetrads appeared in 1967 and 1968 as well as 1949 and 1050.

“The most unique thing about the 2014-2015 tetrad is that all of them are visible for all or parts of the USA,” says longtime NASA eclipse expert Fred Espenak.

See more: http://science.nasa.gov/science-news/science-at-nasa/2014/27mar_tetrad/