Thousands of people across northeastern Oklahoma are asking the same question today: So what WAS it?
The "it" in this case was a very loud boom that was heard and felt at about 8 p.m. Saturday, January 25, 2014. Moments after it happened, the News On 6 social media accounts were jammed with people wanting to know if anyone else had heard and felt it.
The police and fire department scanners in the newsroom crackled to life with dispatchers telling crews in the field about all the calls to 911 about it.
People across the News On 6 viewing area reported a very similar experience: a boom loud enough to be heard indoors that shook windows and even rattled doors. It's understandable why they would want to know what caused it. That goes double for those of us here at News On 6.
So far, no one has reported any kind of damage attributed to the boom. No one has reported seeing a flash of light that would be consistent with an explosion. No one has reported any cracks in their walls or foundations that would be consistent with an earthquake. There was no severe weather in the area at the time so a lone crack of thunder seems unlikely.
So what about a sonic boom? As we noted Sunday, the U.S. Air Force operates several different types of aircraft that are easily capable of supersonic flight.
The 138th Fighter Wing based at Tulsa International Airport flies F-16 Falcons, which have a top speed of more than twice the speed of sound. A spokesman for the 138th says the unit usually flies Monday through Thursdays and its jets were "put up" this weekend.
Vance Air Force Base near Enid trains pilots for the U.S. Air Force. It uses T-38 Talons, which are supersonic aircraft. A spokeswoman says none of that base's jets could have created the sonic boom because the syllabus that the pilots use does not involve breaking the sound barrier.
A spokeswoman for the U.S. Air Force Press Desk at the Pentagon says her office has no effective way of learning if the boom was caused by a USAF jet.
Major Natasha Waggoner tells News On 6 it's Air Force policy not to break the sound barrier below 30,000 feet over land. If a pilot does it accidentally, she says the pilot is required to report it to his or her unit upon landing.
Major Waggoner says it's possible an Air Force (or other U.S. military) jet flying cross country broke the sound barrier as it crossed over northeastern Oklahoma on what the crew considered a routine flight.
The Air Force does not usually comment on its operations, even if they're routine, because of security concerns.
A sonic boom may be the most likely - and least satisfying - explanation for what so many Oklahomans heard and felt. If the atmospheric conditions are right, an airplane exceeding the speed of sound while flying six or seven miles up would cause a shock wave that could be felt over a huge area.
An airplane flying that high and fast would be many miles away before its shock wave traveled to the ground, where it would be experienced as a boom.
Sonic booms caused by military jets were fairly common in the U.S. until the early 70s, when complaints from the public prompted the government to adopt rules to limit them.