I wonder about a merger of a pair of supermassive black holes, say a billion solar masses each. Would it sterilize the whole galaxy? A galaxy is a pretty dange

I wonder about a merger of a pair of supermassive black holes, say a billion solar masses each. Would it sterilize the whole galaxy? A galaxy is a pretty dangerous place to be. Probably we should get clear at first opportunity. A pretty big pair is scheduled to merge sometime in the next three years. Probably we will get enough warning to be watching carefully when it happens.