A Mathematical Symetry in this Sky Sign never seen before.

 The last "Tetrad" of Blood Moons was in 2015.

#1 There was also a total Lunar Eclipse on January 31, 2018

#2 The longest Lunar Eclipse in 150 Years will be on July 27, 2018

#3  The next Lunar Eclipse will be January 21, 2019

It will result in a Blood Moon.  But the Math associated to create these Blood Moons only on Shabbats and

 on Jewish "Feast Days" in exactly the pattern below has not been done ever with this symetry ever.  Not once in history.  Further, this Tetrad is a mirror image of the one in 2014-2015.  Exact number of days between.  Exact everything.  The numerical probablity of this is astronomical.  Think about it. People have been watching for this particular Tetrad for many, many years.

Credit to:The Apocromancer On Youtube. 

The times displayed are accurate within 2-3 seconds.
The magnitude of the eclipse is 1.609.
The penumbral magnitude of the eclipse is 2.679.
The total duration of the eclipse is 6 hours, 14 minutes.
The total duration of the partial phases is 2 hours, 12 minutes.
The duration of the full eclipse is 1 hour, 43 minutes.

An Eclipse Never Comes Alone!

A solar eclipse always occurs about two weeks before or after a lunar eclipse.
Usually, there are two eclipses in a row, but other times, there are three during the same eclipse season.
All eclipses 1900 — 2199
This is the second eclipse this season.
First eclipse this season: 13 July 2018 — Partial Solar Eclipse
Third eclipse this season: 11 August 2018 — Partial Solar Eclipse

Credit:  https://www.timeanddate.com/eclipse/lunar/2018-july-27