You can call it a “blood moon”, “a harvest moon”, or a “supermoon” . . . whatever you name it, the type of total lunar eclipse that took place September 27, 2015 hadn't happened in 32 years and won't happen again until 2033. Learn about the difference between a solar eclipse and a lunar eclipse and discover why the moon turns red as a shadow encroaches—hence the name "blood moon." En Español