Twitter lit up on Saturday (November 29, 2014) as hundreds of witnesses reported hearing a sequence of mysterious and inexplicable loud bangs and booms that continued echoing throughout the United Kingdom for up to 30 minutes. Around the same time, reports of a similar strange noise began arriving from France, Denmark, Belgium, Australia and the eastern United States leading many to suspect the booming noise was the sound of a “pulse detonation engine”, the power source behind the United States’ top-secret Aurora aircraft project. Days after the event, there was still no official explanation for the mysterious noises.

Brits begin reporting odd series of “booms”

At around 10:00 PM local time, hundreds of Twitter users from Aberdeen to Devon in the United Kingdom began reporting “explosions” which shook windows, woke up sleeping children, and set the dogs to barking. The sounds were described variously as “echoing booms”, “high-caliber gunfire”, “jet cannons”, and “distant fireworks”.  The first reports of the mysterious booms arrived from Bedfordshire, Glasgow, North Devon, Leicestershire, Fareham, and West Sussex – areas that are hundreds of miles away from each other. One bleary-eyed resident, who said she listened to the noises for about a half hour, recorded the bizarre sounds on her smartphone (listen to audio recording below) and explained:

“I was just at home watching TV when I couldn’t hear the program due to the loud noises. It was very distracting as it went on for ages. I went out to look for fireworks, but I couldn’t see anything in the sky. That’s when I recorded the clip to send to my family to see if they could hear the same thing.”

The woman reported that indeed, her family members had heard the same sounds.  You can listen to her recording below.

Around the same time, another witness reported being alarmed at the ferocity of the burst of noise.

“I’m from London my sister is from Kent we both heard the noises which sounded like a mini war was going off, bomb explosions, automatic gunshots and other weird noise. It basically sounded like someone had the biggest speaker in the world hooked up to Call of Duty video game and I’m not exaggerating.”

Reports of mysterious booms arrive from other distant areas

Within an hour, a mysterious boom was reported by a number of people on the eastern coast of the United States. Residents of Buffalo, Cheektowaga, and Clarence, New York described it as loud enough to shake their homes and rattle windows. About an hour later, reports of explosive booms began arriving from France, Denmark, Belgium and even Australia. One Brussels resident reported:

“I first thought it was firework, but it was different. Maybe thunder, but the sky was clear, and I didn’t see lightning, even far away.”

Another witness in the area reported hearing the same strange sounds:

“Yesterday at about 1900 hours, I heard lots of loud bangs. I went outside thinking I would see fireworks lighting up the sky – nope. So then I thought maybe it was gun fire because where I live you often hear gun fire at night – (poaching scum bags who enjoy ‘lamping’ and killing innocent creatures). However – it sounded a bit more muffled than gunfire – it was strange. I was a bit puzzled. It lasted about 30 minutes and was sporadic.”

Possible causes for the strange noise

Some have speculated the noises in Britain were geological (i.e. earthquakes, tremors) but that does not explain how the sounds could be heard thousands of miles away. Others suggest meteorological and even space debris from old satellites entering the atmosphere. One piece from the Russian satellite Kosmos 2251 was scheduled for re-entry but the timing did not fit the reports of the UK noises. Besides, meteors or space debris would have been seen falling from the sky which was crisp and clear on the night the noises were heard.

Other potential explanations include space weather, electrical phenomenon, high-speed alien aircraft, and fireworks (fireworks were reportedly exploded in Croydon but not in the other places).

Pulse Detonation Engine?

One scientist theorized the noise was the sound of a pulse detonation engine (PDE), which works by using the force from a series of “explosions” (or pulses), caused by mixing a fuel mist and air intake, to thrust an aircraft forward. It can theoretically power planes at five times the speed of sound and has long been rumored to be the power source for the United States’ top-secret Aurora spy plane. If the sound was created by a PDE power source, it is worth noting that it may not be local at all. Steven Aftergood, government secrecy expert at the Federation of American Scientists explained:

“Because the sound wave that causes the boom can be reflected by the stratosphere, the source of the event could conceivably be hundreds or thousands of miles away from the place where it is heard on the ground.”

Similar 2013 report under odd circumstances

Coincidentally, one local resident reported a similar incident that he witnessed for about two hours in 2013 in the same area.  He wrote:

“I was out all night in early June 2013. There were lights all over the place. Not like lightning, but little flicks everywhere. There were booming sounds in the sky, too. I went up to a high vantage point and could see the flashing lights over the whole landscape. This was in Cornwall. I was so gobsmacked walking around in this craziness. I had my friend’s dog with me who was loving it and very excited. The lights were definitely not lightning. The sky was clear of clouds.”