Gen 1:14 - And God said, Let there be lights in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years:
The word translated as "seasons" is the Hebrew word "moadim" which means appointed times.. So we have the Sun, Moon, and stars created to mark "appointed times" and act as "Signs" .
The Hebrew alphabet has 22 letters and each has a word symbol association and a numerical value. The last letter in the alphabet is "Tav". It has the symbol of an X or cross and means "Sign". It also has the numerical value of 400.
An extremely rare phenomenon to the Earth, if not completely unique, is the fact that the diameter of its moon is not only 400 times smaller than the Sun but 400 times closer to the Earth. This of course allows them to look identical in size from the perspective of Earth and also allows the moon to fully eclipse the sun when they align properly.
Throughout history there have been many significant events seemingly marked or heralded by solar and lunar eclipses. The upcoming August 21st, 2017 full Solar eclipse casting it's shadow across the United States shares the same August 21 date as the full solar eclipse that traversed over Europe and the Middle East in 1914 marking the beginning of World War I.
The celestial signs unfolding for the years of 2017/18, (5777, 5778 on the Hebrew Calendar) appear very significant beginning with the August 21st eclipse followed 33 days later by the Sept. 23rd fulfillment of the Revelations 12 sign. ( See my article Signs and appointed times for details on the Sept 23rd sign in the heavens)
Another interesting fact is the temperature of the Surface of the Sun is 5778 degrees Kelvin. A temperature measuring system that has only been around since 1848. Is it possible that the we are being told in these last days through the increase in knowledge that the Hebrew year of 5778 / 2018 which just happens to be the 70th anniversary of the State of Israel is the year the Messiah Yeshua returns to establish the Millennial Kingdom?
May God bless you and keep you through these exciting times.