The American Meteor Society said a boom heard by residents in multiple states Saturday afternoon was a 3-foot wide meteor entering the atmosphere near the Massachusetts and New Hampshire border. Police and fire agencies across Massachusetts and Rhode Island received reports of buildings shaking, and videos of a double boom were posted on social media, without any smoke, fire or other visuals that would explain it. But dozens of people from Montreal to Delaware reported seeing the fireball enter the atmosphere Saturday, likely landing in the ocean if it didn’t burn up in the atmosphere, experts said.