At the Discovery Science Center in Bridgeport, they’re used to talking about earthquakes. But they rarely get to experience one – until Friday.

“I was surprised, but I was very excited,” said Kate Oliver, the museum’s STEM program director. “This is right up my alley.”

Kate Oliver said tremors this strong are very unusual in the Northeast, but they can happen.

“The North American Plate – we’re pretty solidly in the middle of it. We’re not near any plate boundaries,” she said. “But there could be fault lines from old movements happening.”

And earthquakes in the local area can actually feel stronger than they are because of the hard rock beneath the East Coast.

“It’s like when you blow up a balloon too far,” Oliver said. “Eventually, it’s going to pop.”

Michele Chockey, of Fairfield, stopped by the museum minutes after the quake. Being from California, she immediately recognized it. “The shaking, how it was, it was sort of like this,” she said, shaking her hands left-to-right. “I’ve known it from living in California, and how they felt, but it was a little unsettling being in Connecticut, feeling it.”

The last significant East Coast earthquake was in 2011 – an even stronger 5.8 magnitude based in northern Virginia.

Friday's quake shook skyscrapers and suburbs across the northeastern U.S., causing no widespread damage but startling millions of people in an area unaccustomed to temblors. The U.S. Geological Survey said over 42 million people might have felt the midmorning quake with a preliminary magnitude of 4.8, centered near Whitehouse Station, New Jersey.

Aftershocks were reported hours later in a central New Jersey township, producing some reports of damage and items falling off shelves, Hunterdon County Public Safety Director Brayden Fahey said.

Earthquakes are less common on the eastern than western edges of the U.S. because the East Coast does not lie on a boundary of tectonic plates. The biggest Eastern quakes usually occur along the Mid-Atlantic Ridge, which extends through Iceland and the Atlantic Ocean.

But rocks under the East Coast are better than their western counterparts at spreading earthquake energy across long distances.

“If we had the same magnitude quake in California, it probably wouldn’t be felt nearly as far away,” said U.S. Geological Survey geophysicist Paul Caruso.

A 4.8-magnitude quake isn’t large enough to cause damage, except for some minor effects near the epicenter, the agency posted on the social platform X. By comparison, the temblor that killed at least 12 people and injured more than 1,000 in Taiwan on Wednesday was variously measured at a magnitude of 7.2 or 7.4.

Earthquakes with magnitudes near or above 5 struck near New York City in 1737, 1783 and 1884, the USGS said. Friday's rumbles also stirred memories of the Aug. 23, 2011, earthquake that jolted people from Georgia to Canada. Centered in Virginia, the 5.8-magnitude quake was the strongest earthquake to hit the East Coast since World War II.