For those who want a really good and decisive explanation as to the identity of the Red Dragon in Revelation, and just what it means to have 'days of darkness,' my lengthy essay on my Occult Physics website does give the answer.
It is a solution that is backed up by science, and really solid physical processes.
Specfically, when certain special conjunction patterns are established in the heavens, the sun cancels its light waves and there is a resonant agitation of the planets, creating massive destructive seismic activity.
The full article is here: http://www.occultphysics.com/Revelation.html