An apparent meteor passing through the atmosphere just east of Boston caused a loud boom heard over multiple areas of Massachusetts around 2 p.m. on Saturday, according to Ken Mahan, lead meteorologist for the Boston Globe.
“It’s a bolide meteor, which is essentially a fireball,” Mahan said. “These are large and often spark a sonic boom when passing through the atmosphere with speeds faster than the sound barrier and air compressing ahead of the meteor as it races through, generating a massive pressure wave.”
“The average size bolide meteor sits at 1-2 meters,” he added. “NASA will ultimately estimate the size of this meteor in the coming days.”
In a post on X Saturday, the Massachusetts Executive Office of Public Safety and Security said “there are no known emergency police or fire requests connected to” reports of the sonic boom caused by the apparent meteor.
The agency did not confirm that the boom was caused by a meteor.
“We remain in contact with our local, state, and federal partners to monitor any impact and understand the cause when it becomes available,” the statement said.
John Ebel, a senior research scientist at Weston Observatory in Boston College, said in a phone interview Saturday that if not for heavy cloud cover, a fireball might have been visible over the Massachusetts coast.
“It must have gotten pretty far into the atmosphere,” he said, adding that sound waves from meteors entering the upper atmosphere usually dissipate by the time they reach the ground.
Ebel said an earthquake couldn’t have caused the sound because atmospheric pressure waves, which come from the sky, were much stronger than seismic signals he detected on the ground.
“My automated system for detecting earthquakes didn’t trigger,” he said.
Mahan said small meteors enter the atmosphere all the time, but typically don’t make a sound as loud as the one heard Saturday afternoon.
The apparent meteor “had to be much larger and traveling faster than normal meteors to make a sound this loud,” he said.
James Ryan, a professor emeritus of physics and a researcher at the Space Science Center at the University of New Hampshire, said satellite imagery of the shockwave is “consistent with a good-sized meteor.”
“Meteors cast a very wide range of sonic booms,” he said.
Ryan referenced a 2013 incident in Russia when a meteor the size of a bus entered the atmosphere in a blinding fireball, causing a shockwave that shattered windows and collapsed part of the roof of a zinc factory.
“The sonic boom is a shockwave and if intense enough, can be dangerous,” he said.
Truman Dickerson can be reached at truman.dickerson@globe.com.