When they say one megaton, do they mean total energy released during entry or something? There's no way we're having the equivalent of a one megaton nuke (minus

When they say one megaton, do they mean total energy released during entry or something? There's no way we're having the equivalent of a one megaton nuke (minus the fallout) on the surface every fifteen years ... Or are we just in a dry patch? Edit: The actual paper says 'impact' so I don't know what to think here.