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In Total Penumbral lunar eclipses, Jean Meeus, 1980
The frequency of tetrads varies by century with the frequency of total lunar eclipses. This repeating cycle is called a tetradia. See
In astronomy
Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall evolution. Objects of interest includ ...
, a tetrad is a set of four total lunar eclipse
A lunar eclipse is an astronomical event that occurs when the Moon moves into the Earth's shadow, causing the Moon to be darkened. Such an alignment occurs during an eclipse season, approximately every six months, during the full moon phase, ...
s within two consecutive years.The frequency of tetrads varies by century with the frequency of total lunar eclipses. This repeating cycle is called a tetradia. See
Eclipse cycle
Eclipses may occur repeatedly, separated by certain intervals of time: these intervals are called eclipse cycles. The series of eclipses separated by a repeat of one of these intervals is called an eclipse series.
Eclipse conditions
Eclipses ...
for more information.
List of tetrad events
1949–2000
2001–51
See also
* for statistics by century * Blood moon prophecy Apocalyptic preaching ofJohn Hagee
John Charles Hagee (born April 12, 1940) is an American pastor and televangelist. He founded John Hagee Ministries, which telecasts to the United States and Canada. He is also the founder and chairman of the Christian Zionist organization Chr ...
and Mark Biltz in part based on the observed phenomenon.
References
{{Lunar eclipses Lunar eclipses