Not one big enough to cause another great extinction, but small enough to just turn a whole small country and parts of neighboring ones into a huge crater. Will the people who was evacuated out after NASA stated a warning try to rebuild the country after everything has settled down or do they’d become citizens of another country?
Meteor
Meteor impacts are typically expressed by converting their kinetic energy into its TNT equivalent.
https://en.wikipedia.org/wiki/Torino_scale