The earthquake that hit the Northeast on Friday morning rattled nerves but did not do much damage. Still, it left many New Yorkers wondering how afraid they should be of a bigger one hitting closer to the city. The answer? It’s hard to say. Some news reports suggest that a large earthquake is “due” in New York City because moderate ones — with a magnitude of 5 or more — typically occur every few hundred years. The last one took place in the 1700s. Friday’s earthquake, in comparison, was a magnit