“…there will also be deceptions which are so subtle that even the elect themselves might be fooled. Then the sign of the coming of Christ: it will be sudden, from above, and not like His first coming. The signs of the very end are that “the sun shall be darkened, the moon shall not give its light, the stars will fall from heaven”; and then Christ Himself will appear in the heavens with the sign of the Cross.”
(Fr Seraphim Rose+ ‘Contemporary Signs of the End of  the World’)