Depends on factors both human and natural.
Atomic War-as long as you have the weapons they can be used.
Yellowstone caldera any time.
Meteorite, never know when it will be a Planet Killer.
Depends on factors both human and natural.
Atomic War-as long as you have the weapons they can be used.
Yellowstone caldera any time.
Meteorite, never know when it will be a Planet Killer.