These are *Cosmic Events* Solar and Lunar Eclipses, and what will cause a *Great Earthquake* IMO Comet Elenin in our solar system...
Often used in the Old Testament context as a metaphor for great political changes, empires falling, that sort of thing. Not, I know, how a lot of people are wont to interpret John's Apocalypse. Fact, none the less.
Comet Elenin
You might want to consult some actual astronomical websites about it, instead of the whackadoodle stuff.
The Star of Bethlehem was not a metaphor, it was an actual cosmic event....When Jesus asended to the Father, it was not a metaphor, he went up in a cloud that hid him and this was seen by his diciples.....
Signs and Seasons are not metpahors, they were used as a *Harvesting* and biblical holy days in the OT....