Historically comets have come before wars, seen as bad omens of deaths of kings or noble men or a warning of forthcoming danger. See my blog of 9/25/11 Significant Comets Connection to Historic Events.
Comet ISON was discovered by September 21, 2012 by 2 Russian Astronomers, Vitali Nevski and Artyom Novichonok. Since they were using a telescope that belonged to International Scientific Optical Network (ISON) the comet was named after the network and not by their names (i.e., Halleys Comet found by Edmond Halley).
Comet ISON could be the brightest comet in history, time will tell. We will see what happens as it approaches the sun November 28, 2013.
The significance I see is that it is expected to be the brightest comet in history and it will be in our viewing during the first of the tetrad Blood Moon over Passover of 2014.
When the signs are in the heavenlies over God’s appointed festivals (Feasts of the Lord) it is calling us to attention, watch. Luke 2:25, “And there will be signs in the sun, in the moon, and in the stars; and on the earth distress of nations, with perplexity, the sea and the waves roaring; (28) Now when these things begin to happen, look up and lift up your heads, because your redemption draws near.” (Also Daniel 6:26-27; Joel 2:31; Isaiah 34:2-5)[my comment- look up, WATCH the heavenly signs]
Genesis 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:

