After some northern Utah residents reported hearing "booming" noises and feeling earthquake-like shaking Monday night, the 388th fighter wing at Hill Air Force Base confirmed that it was one of their jets during a training.
The wing had previously announced that it is conducting required night combat training this week as late as 9:30 p.m. — right around the time the rattling was felt and heard.
On Tuesday, the wing tweeted that it was a sonic boom from one of its planes over the Utah Test and Training Range, which is in the West Desert midway between Tooele and Wendover.
“These sonic booms happen when these military aircraft fly at supersonic speeds," said Katherine Whidden, a research scientist with the University of Utah Seismographic Station (UUSS). "If the weather conditions are just right, like they were yesterday, that could be felt on the ground. People could... hear something or people might feel shaking.”
The wing wrote that a sonic boom occurring out there would not normally be felt or heard in the Wasatch Front, but the inversion layer can cause the energy and sound to travel farther. The topography of the basin and mountain ranges can also exacerbate this, they said. Whidden affirmed that science Tuesday.
"All of us in the 388th Fighter Wing do our best to be good neighbors, and appreciate the support of all the communities in Northern Utah as we train for our combat mission," the wing tweeted, adding that the pilot was approved for supersonic flight in that airspace and was in compliance with regulations.
And although the UUSS confirmed right away Monday night that it was not an earthquake, they did actually detect the disturbance.
“It’s different from an earthquake in that it’s an atmospheric source — it’s a source that comes from above us in the air, whereas an earthquake of course comes from the ground," Whidden said.
We’ve heard some reports of people hearing “booms” and feeling shaking along the Wasatch front. While it was energetic enough to be recorded by our seismometers, the waves are traveling too slowly to be seismic. Aka not an earthquake. pic.twitter.com/vrWUwT9HI4
— UUSS (@UUSSquake) January 26, 2021