April's pre-Easter 'Blood Moon' has apocalyptic conspiracy theorists chattering

For the third time in two years, stargazers and apocalyptic doomsayers Saturday are getting their fill of unique celestial events with a total lunar eclipse.

Lunar eclipses happen about twice a year when the moon passes directly behind the Earth into its shadow, or umbra. Total lunar eclipses, or "blood moons" are a little more rare.

But what's up with the creepy red glow that gives the lunar event its nickname?

Well, the red color is actually not unlike a sunset, but from the moon's perspective. NASA describes it as "seeing every sunrise and every sunset in the world, all of them, all at once." And that red glow from behind the Earth gets projected onto the moon.

This total lunar eclipse is the third in a series of four appearing every six months, a phenomenon called a "tetrad" – something not particularly rare for this century according to NASA.

While a total lunar eclipse is a fun night sight for skywatchers, for others the oncoming blood moon and tetrad brings something else – tidings of doom.

As CTV News points out, a number of conspiracy sites suggest links between lunar eclipses and major historical events, including the fall of Constantinople and the founding of the State of Israel. In fact, the last blood moon outside this current tetrad occurred when the Red Sox won the World Series in 2004.

But perhaps the biggest proponent for any conspiracy concerning the upcoming blood moons is Pastor John Hagee, who released a book titled "Four Blood Moons: Something Is About to Change in 2013."

In a 2013 interview with Fox News, Hagee emphasized the significance that each blood moon will occur during a Jewish holiday.

"To have a blood moon, and then for those blood moons to be on this exact date, is something that just is beyond coincidental."

All four of this recent set of blood moons are viewable from the U.S., which Hagee claims is further proof of impending doom in America.

The last of the four blood moons in this tetrad will be viewable later this year on September 28.

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