Home   Sun & Moon   Eclipses   Blood Moon

What Is a Blood Moon?

Blood Moon may originate from the red glow a Full Moon get as Earth casts its darkest shadow, the umbra, on it. The term is sometimes used to describe 4 total lunar eclipses that occur in a row.

Illustration image

A total lunar eclipse can be a Blood Moon.

Blood Moon is sometimes used to describe 4 total lunar eclipses in a row.


Lunar Tetrad

Total lunar eclipses do not occur often – only about 1 in 3 lunar eclipses are total, and about 4 to 5 total eclipses can be seen from any single location on Earth in a decade.

Every once in a while, however, 4 total lunar eclipses happen in a row. This rare occurrence is called a lunar tetrad. The eclipses in a tetrad occur 6 months apart with at least 6 ll s between them.

Blood Moons & the 2014–2015 Lunar Tetrad

Illustration image
2014–2015 lunar tetrad.
2014–2015 lunar tetrad.

The 2014–2015 lunar tetrad gathered a lot of attention because of claims by some religious organizations that the eclipses in the tetrad were a sign of the end times. Some even called the eclipses Blood Moons after a statement in the Book of Joel, that referred to the Sun turning dark, and the Moon turning red before the second coming of Jesus.

Christian pastors Mark Blitz and John Hagee are thought to have been instrumental in popularizing the idea of the prophetic nature of the 2014–2015 Blood Moons, which had special significance because they coincided with important Jewish festivals. The April 15, 2014 and April 4, 2015 Total Lunar Eclipses occurred at the same time as Passover, while the October 8, 2014 and September 28, 2015 eclipses occurred during the Feast of Tabernacle.

The 2014–2015 Lunar Tetrad or Blood Moons were significant for an additional reason – all 4 total lunar eclipses were visible from most of the United States. The September 28, 2015 eclipse was the last total lunar eclipse visible from mainland USA until January 31, 2018.

Another Prophecy That Never Came True

Reports of impending doom due to the Blood Moon Prophecy were clearly exaggerated, especially since 8 tetrads since 1 C.E. have coincided with Jewish holidays without the world going under. In fact, prior to the last eclipse of the 2014–2015 tetrad, many religious organizations debunked the doomsday claims and reassured their followers that the world wasn't going to end anytime soon.

Blood Moons or Red Moons?

While Blood Moon is not an astronomical or scientific term, it can be used to describe any total lunar eclipse. This is because a Full Moon very often turns red when completely eclipsed. This happens because of Rayleigh scattering, the same mechanism that causes colorful sunrises and sunsets.

How Often do Lunar Tetrads Happen?

It depends on the century you look at. Italian Astronomer Giovanni Schiaparelli calculated that the occurrence of lunar tetrads varies over centuries. Some 300-year intervals have several lunar tetrads, while other 300-year intervals do not have any. For example, the years between 1582 and 1908 did not have any tetrads, whereas the next 250 years – from 1909 to 2156 – will have 17 tetrads.

When's the Next Blood Moon?

According to NASA, the current century – 2001 to 2100 – will have 8 tetrads. The first tetrad of the 21st century took place in 2003, the second was in 2014–2015 and the next Full Moon will be in 2032–2033, with the following eclipses:

Topics: Astronomy, Eclipses, Moon

Next Total Lunar Eclipse


Total Lunar Eclipse

Jan 31, 2018 at 10:51:13 UTCSee more


Eclipse Lookup

Lunar Eclipses

  1. Total Lunar Eclipse
  2. When Is the Moon Red?
  3. Partial Lunar Eclipse
  4. Penumbral Lunar Eclipse
  5. Can I See a Lunar Eclipse?
  6. Blood Moon - Total Lunar Eclipse
  7. Magnitude of Eclipses


Eclipse Shadows

  1. Umbra
  2. Penumbra
  3. Antumbra

Why Are There 3 Shadows?

You might also like

2017 / 2018 Cosmic Calendar

List of cosmic events in 2017 an 2018 including supermoons, solar and lunar eclipses, meteor showers, solstices, and equinoxes. more

Why 3 Shadows?

The Earth and the Moon cast 3 different shadows: umbra, penumbra, and antumbra. Why are there 3 types of shadows and how are they defined? more