Turn your gaze to the stars tonight for an eerie and spectacular view of the “blood moon.” At 12:53 a.m. ET, the Earth will begin to position itself between the sun and the moon for the first of a series of four total eclipses to conclude in September 2015.
The phenomenon is known as a tetrad, in which the moon is completely covered by the earth’s umbral shadow for four eclipses in a row, as opposed to only partial eclipses that fall in the outer penumbra. But rather than succumbing to complete darkness, the moon will glow red as it receives the refracted light that spills over the Earth’s circumference.
The series is a rare occurrence in history, with large spans of time, such as the 300 years between 1600 and 1900, witnessing none.
“Frequency sort of goes through 585-year cycles, So you go through centuries where you don’t have any, and centuries where you have a number of them.”