NEW YORK (FOX5NY.COM) - Three weeks ago, seismographs around the world detected seismic waves but according to reports no one felt them.
"I actually have no idea what happened on November 11th," Stephen Holler, a Fordham University associate professor of physics, told Fox 5.
Holler said the seismic station under the bedrock at Fordham detected those waves, too. The station has been monitoring seismic activity on campus from a concrete bunker since the Great Depression.
Holler showed us evidence of the shaking earth in New York City that the station observed on Nov. 11.
"The most likely explanation for this one was some sort of volcanic activity," he said. "Maybe some shifting of magma underneath the surface of the earth or the collapse of one of the magma activities."
It was not likely an underwater eruption but perhaps an early indicator of one in the region where those waves appeared to originate—near the island of Mayotte in the Indian Ocean between Madagascar and the rest of the African continent.
"There's a volcano over there obviously," Holler said. "I don't know if it's ready to erupt or not."
Holler dismissed theories of asteroids, the supernatural, or an alien spaceship. Instead, he called the low-frequency waves almost certainly geological in origin.
"There is a mystery to be solved," he said. "But how big it is I don't know."