It is an amazing thing, and no one could have engineered that. Such activity helps our planet stay stable for life to thrive. I would like to read about that extraterrestrial impact you mentioned. Even though we have little evidence, that collision might really have weakened the crust and started the plates moving. But who knows, maybe someone out there is really powerful enough to execute all these things, far beyond what humans can do. Thank you. :)
RE: How unique is Earth? New evidence shows it’s the only planet with unique and active plate tectonics - moving for 3.5 billion years.