A Blood Moon is a non-scientific description of the Moon that can appear with a rusty-red color.
This phenomenon happens when the Moon goes through a total lunar eclipse.
A Blood Moon can also refer to a series of four total lunar eclipses which is very rare.
During a total eclipse, the Moon is fully in Earth’s shadow but at the same time, some light from Earth’s sunrises and sunsets fall onto the Moon. When the red light reaches the surface of the Moon, it appears red.