Eclipse of super blood moon signals end of tetrad
September 28, 2015
In a span of two years the world has had the opportunity to witness four full lunar eclipses. This cycle of rapid succession is known as a tetrad and was brought to an end with the perigee full blood moon which lasted from Sept. 27-Sept. 28. According to astronomers, the phenomenon of a super moon aligned with a full lunar eclipse will not repeat until 2033.