“You couldn’t miss it,” he said.
The fire department immediately began receiving calls from residents inquiring about the explosion. Mr. MacDonald said he was still not sure.
“Fortunately, I had been to church this morning,” he said. “So I felt prepared.”
Dylan Mei, a dispatcher with the Winchendon, Massachusetts Police Department, said three townspeople called to report the “ground was shaking.” WCVB-TV reported that many residents emailed the station to share stories of hearing a loud boom and feeling the ground shake.
Don Blakeman, a geophysicist with the US Geological Survey, said on Sunday that the National Earthquake Information Center had detected no seismic activity in the area on Sunday. But that doesn’t entirely rule out that there was a minor earthquake, he said.
New Hampshire often experiences small earthquakes, said Jessica Turner, a geophysicist for the US Geological Survey. The last time was on Aug. 22, when a magnitude 1.7 earthquake was recorded in an area south of Rochester, New Hampshire, Ms Turner said.
Paul D. Raymond Jr., administrator of strategic communications for the New Hampshire Department of Security, said in an email Sunday that the agency had seen people commenting on the noise online.
He said the statewide 911 center received only one call of a large boom around 11:30 a.m. in Lyndeborough, New Hampshire, and no call to the dispatch center of the state police. Mr. Raymond pointed out that more than 400 people had shared their observations on volcandiscovery.com, a website where people can report seismic activity.
Mr Brian, who discussed his experience on Twitter, pointed out that his home is near the New Boston Space Force Station, a satellite tracking station that has been recently transferred from Air Force to Space Force.