Delton Boom?

Last night I had just unloaded the dishwasher and was walking back into the living room when the house was shaken by a large boom And I mean shaken. We couldn't figure out what it was and even went out to check and make sure no neighborhood home had exploded. No sign of anything.

Back in April of 2012, there were reports of such booms in nearby Baraboo. Here is an account from a Madison television station: 

Neighborhoods on Baraboo's southwest side woke early Sunday morning to a loud boom, and less than an hour later, another one. Both booms accompanied by a flash of light. More than a dozen callers described the sounds of an explosion, blasting dynamite or a gunshot.

A police officer on duty was parked along 8th Street at about 1:45 a.m. Sunday when he heard the boom and saw the flashing light. He immediately thought a transformer blew...

But it wasn't. Alliant Energy told authorities they had no outages or transformer problems.

27 Storm Track meteorologists say it is highly unlikely that what Baraboo experienced was weather related, because no storms traveled through the area -- leading Schauf to the only explanation he can think of: fireworks.

"There's no evidence to suggest that there's anything other than a man made cause at hand," Schauf says.

But many of those who've heard it say it sounded much more intense...

Police say there's little they can do now, unless the city hears more booms.

Tom has suggested that the Baraboo boom has moved to Delton. Rich opined that it was a sonic boom, which is not nearly as esoteric as some of the theories floated after the Baraboo boom and similar booms in a few other communities two years ago, which theories included CO2 sequestration storage, which has been documented to cause “small to moderate earthquakes,” improper disposal of wastewater from a natural gas fracking operation (also documented to cause earthquakes), or more exotic explanations such as the High Frequency Active Auroral Research Program (HAARP) or secret underground military tunneling."

High Frequency Active Auroral Research Program? Here's Wikipedia on that:

The High Frequency Active Auroral Research Program (HAARP) is an ionospheric research program jointly funded by the U.S. Air Force, the U.S. Navy, the University of Alaska, and the Defense Advanced Research Projects Agency (DARPA).Designed and built by BAE Advanced Technologies (BAEAT), its purpose is to analyze the ionosphere and investigate the potential for developing ionospheric enhancement technology for radio communications and surveillance.The HAARP program operates a major sub-arctic facility, named the HAARP Research Station, on an Air Force–owned site near Gakona, Alaska...

HAARP was a target of conspiracy theorists, who claimed that it was capable of modifying weather, disabling satellites and exerting mind control over people, and that it was being used as a weapon against terrorists. Such theorists blamed the program for causing earthquakes, droughts, storms and floods, diseases such as Gulf War Syndrome and Chronic Fatigue Syndrome, the 1996 crash of TWA Flight 800, and the 2003 destruction of the space shuttle Columbia. Commentators and scientists say that proponents of these theories are "uninformed", because most theories put forward fall well outside the abilities of the facility and often outside the scope of natural science .