In astronomy, the term blood moon refers to a complete lunar eclipse which causes the moon to appear red. The moon looks red due to dispersed light from Earth's sunrises and sunsets that is refracted back onto the moon's... More »

A blood moon does not signify anything. It is a total lunar eclipse that turns a rusty red-orange or a deep blood-red color while it is in Earth's shadow. Sunlight filters through Earth's atmosphere and reaches the moon ... More » World View Symbolism

The dates of the 2015 blood moons are April 4th and September 15th. These dates are the final two of the 2014 to 2015 Lunar Tetrad, the first two being April 15th and October 8th of 2014. More » Science Earth Science

The term "gibbous moon" refers to the phase of the moon's cycle when more than half but less than all of the moon is illuminated by the sun, making it visible from Earth. A gibbous moon can be either waxing or waning, ex... More »

A blood moon is a deep reddening of the moon caused by the Earth passing between the moon and the sun. During the period of the eclipse, light from the sun passes around the Earth and through its atmosphere. This scatter... More » Science Astronomy Our Moon

A blood moon, or lunar tetrad, does not occur on a regular schedule. However, the blood moons of 2014 and 2015 are not isolated events. Between the first century and 2014, there were 62 lunar tetrads. More »

Moon phases occur because the angle of the Earth, moon and sun changes as the moon orbits the Earth. One-half of the moon is always illuminated by the sun. As a person's angle of sight changes, different portions of sunl... More » Science Astronomy Our Moon