[Read directions thoroughly before applying to eyeballs][link]. I still say it is much more likely to come [from within][lavos].
[link]: http://gizmodo.com/5118876/badass-asteroid-destroys-earth-in-high-definition “Gizmodo – Badass Asteroid Destroys Earth in High Definition – Futuremodo”
[lavos]: http://chronocompendium.com/Term/Lavos.html “Chrono Trigger: Lavos”