Twice this week, East Coast residents have been stunned by a sudden boom that rattled their windows and homes and left them questioning what had caused the commotion.<\/p>\n
The latest thundering sound came from a fireball piercing through the air over the Boston area on Saturday around 2 p.m., NASA said.<\/p>\n
The agency said the fireball reached speeds of up to 75,000 miles per hour as it was sucked into Earth\u2019s atmosphere. Forty miles above the Massachusetts border with New Hampshire, the meteor fragmented.<\/p>\n
The energy released as the rock broke up was equivalent to about 300 tons of TNT, accounting for the loud booms, NASA said. The event was not part of a meteor shower.<\/p>\n
Before an explanation emerged, residents in the greater Boston area and Rhode Island had taken to social media to entertain a range of potential causes, including a nuclear attack or even an alien invasion. <\/p>\n
Rich Sauro, of Medfield, Mass., about 40 miles west of Boston, had been lying down in his second-floor bedroom, trying to take a nap. The shades were drawn. He began to nod off. Then he experienced something he never heard before. <\/p>\n
\u201cI thought a car hit my house,\u201d he said. \u201cI opened up the shade in the window and looked out.\u201d <\/p>\n
Mr. Sauro, 64, proceeded like many others in the region: He called the police. <\/p>\n
The Boston Police Department had fielded calls from across the state and officers had been dispatched in the Brighton, Mass., area, about 10 miles from downtown Boston.<\/p>\n
Mr. Sauro grabbed his son and the two ventured around the neighborhood, expecting to find a horrific scene. But they did not encounter anything of note. <\/p>\n
Since it was cloudy over Boston on Saturday, residents may not have had a clear view of the burning rock, said Carl W. Hergenrother, the executive director of the American Meteor Society. The fireball could have been around the size of a basketball, and appears to have landed in the ocean, he said.<\/p>\n
The initial mystery of the sound was partly fueled by the timing.<\/p>\n