Turns out the "sonic boom" heard by many in New Hampshire early Thursday morning was actually a small earthquake, officials at the Weston Observatory said.
Officials at the observatory say the small earthquake, which was 1.6 in magnitude, happened at 2:53 a.m. about 4 miles away from Exeter.
The earthquake was heard in Exeter and Brentwood as a loud explosion, and some in the area felt the ground shaking.
