Strange Sounds • Mystery Booms Archive • 2015
In 2015, people around the world reported sudden house-shaking booms, explosion-like cracks and mysterious rumblings with no obvious source. Some came from meteors tearing through the atmosphere. Others were generated by shallow earthquakes, frost quakes, supersonic aircraft or military activity. Several remain unresolved.
The year also produced several extraordinary mystery-to-solution cases: a meteor shockwave recorded by seismic stations in Switzerland, a Florida fireball that rattled windows with delayed sonic booms, and a bizarre Rhode Island beach explosion eventually linked to hydrogen accumulating beneath the sand.
This archive preserves the strongest documented mystery booms of 2015 while separating the initial mystery from what later evidence revealed.
👉 Explore the science behind these events in the Mystery Booms & Rumblings hub.
2015 Mystery Booms — Key Facts
- Meteors produced some of the year’s best-documented booms. Major fireball events were reported over Florida, New Zealand, central Europe and Scandinavia.
- The March 15 European meteor was detected seismically. Sound waves from the fireball were recorded by stations across northeastern Switzerland.
- Small earthquakes frequently sounded like explosions. Connecticut, Oklahoma, Michigan and Illinois provide clear examples.
- Extreme winter cold produced frost-quake reports. Tennessee residents described sounds resembling explosions, gunfire and even aircraft crashes.
- One mystery beach blast was eventually solved. Scientists concluded that hydrogen gas accumulating beneath Salty Brine State Beach in Rhode Island most likely combusted.
- Several major reports remain unresolved. Hampton Roads, Delmarva, coastal Maine and Pennsylvania all produced credible boom reports without definitive explanations.
What Is a Mystery Boom?
A mystery boom is not a specific geological or atmospheric phenomenon. It describes an observation: a powerful boom, crack, rumble or pressure wave whose source is not immediately apparent.
Witnesses may report windows rattling, buildings vibrating, the ground shaking or a sensation similar to an explosion or earthquake.
Later investigation often reveals an ordinary physical mechanism. Common sources include meteors, sonic booms, shallow earthquakes, frost quakes, blasting and military activity.
How the 2015 events are classified
CONFIRMED — strong instrumental, official or documentary evidence identifies the source.
LIKELY — one explanation is strongly supported, although some uncertainty remains.
UNRESOLVED — the event itself is credible, but available evidence does not establish a reliable source.
UNCERTAIN — the surviving evidence is too incomplete to confidently distinguish between plausible explanations.
January 2015 — Earthquake Booms and Unexplained Winter Blasts
January 1 — Luzerne County, Pennsylvania: New Year’s Day Mystery Boom
Residents in Luzerne County reported a sudden explosion-like boom on New Year’s Day.
The event generated local attention but no sufficiently documented seismic, atmospheric or industrial source emerged to confidently
explain it.
Cause: Unknown
Status: UNRESOLVED
January 8 — Oklahoma: Strange Booms During Cold Weather and Rising Seismicity
Reports of loud unexplained booms surfaced across Oklahoma during a period of both intense winter conditions and unusually high earthquake activity.
That creates an important classification problem. Some individual sounds may have been associated with shallow earthquakes, while cold-weather ground cracking was also considered plausible in some areas.
Oklahoma was simultaneously experiencing a dramatic regional rise in seismicity. Much of that increase was later linked scientifically to wastewater injection. For the broader mechanism, see: Induced Seismicity & Man-Made Earthquakes Explained.
Possible causes: Shallow earthquakes / cryoseisms / local sources
Status: UNCERTAIN
January 12 — Plainfield, Connecticut: M3.3 Earthquake Produces Loud Booming
A magnitude 3.3 earthquake struck eastern Connecticut and was accompanied by widespread reports of loud booming and sudden shaking.
The case provides a useful reminder that even relatively small, shallow earthquakes can sound surprisingly explosive close to their source.
Cause: Earthquake
Status: CONFIRMED
January 27 — Winchester, England: Small Earthquake Produces Explosion-Like Shaking
A small earthquake beneath Hampshire startled residents around Winchester. Witnesses described sudden shaking and rumbling consistent with a shallow seismic event.
Cause: Earthquake
Status: CONFIRMED
February 2015 — Fireball Sonic Booms and Explosive Frost Quakes
February 12 — New Zealand: Bright Meteor Lights the Sky and Produces a Sonic Boom
A brilliant blue-white fireball was seen across a remarkable portion of New Zealand, from the upper South Island to northern parts of the North Island.
Witnesses reported both the flash and a delayed thunderclap-like boom. Astronomers concluded that the object was a substantial meteoroid that probably disintegrated offshore.
The wide geographic footprint makes this one of 2015’s strongest atmospheric-boom cases.
Cause: Meteor / atmospheric shockwave
Status: LIKELY
February 20 — Tennessee: Frost Quakes Mistaken for Explosions and Aircraft Crashes
Emergency dispatchers received reports of powerful booms during an intense cold spell. Witnesses compared the sounds to gunfire, exploding pipes and even aircraft crashes.
The conditions strongly favored cryoseisms.
Frost quakes occur when water-saturated soil or rock freezes rapidly. Expanding ice builds stress until the frozen ground fractures suddenly, releasing a sharp boom and localized shaking.
Cause: Cryoseisms / frost quakes
Status: LIKELY
February 21 — Northern Florida: Brilliant Fireball Produces House-Shaking Sonic Booms
One of the best-documented mystery-boom events of 2015 occurred over northern Florida.
A brilliant fireball generated hundreds of eyewitness reports across the southeastern United States. Many observers around northern Florida reported a delayed boom strong enough to rattle windows, walls and entire houses.
The American Meteor Society mapped the reports and found that the sonic-boom observations clustered near the final portion of the meteor’s atmospheric path.
This is a textbook example of a mystery boom with a clearly identifiable atmospheric source.
Cause: Meteor-generated atmospheric shockwave
Status: CONFIRMED
February 27 — Kerala, India: Fireball, Loud Boom and Apparent Tremor
Residents across parts of Kerala reported a bright fireball followed by an explosion-like sound and apparent shaking.
Investigators considered a meteor or meteoroid fragmentation event the most plausible explanation.
Cause: Meteor / atmospheric airburst
Status: LIKELY
March 2015 — A Meteor Shockwave Recorded by Seismometers
March 15 — Switzerland, Germany & Austria: Meteor Shockwave Recorded by Seismic Stations
At about 20:45 local time, an exceptionally bright fireball crossed central Europe.
Witnesses in Germany, Switzerland, France and Austria reported the event, while people near Zurich heard a powerful delayed sonic boom and prolonged rumbling.
What makes this event exceptional is that the sound waves were not only heard.
Seismic stations across northeastern Switzerland recorded them.
The Swiss Seismological Service detected meteor-generated acoustic signals for roughly four minutes from the Uri region through Glarus and beyond Lake Constance.
Meteor-camera observations also allowed researchers to reconstruct the fireball’s trajectory through the atmosphere.
The 2015 Swiss fireball provides unusually strong evidence connecting an atmospheric meteor directly to both audible booms and signals recorded by ground-based seismic instruments.
Cause: Meteor atmospheric shockwave
Status: CONFIRMED
March 16 — Hampton Roads & Outer Banks: Ground-Shaking Booms Across the Coast
Residents across coastal Virginia and northeastern North Carolina reported loud booms and noticeable shaking.
Military aircraft, offshore activity and atmospheric propagation were among the possibilities discussed, but no sufficiently strong surviving evidence establishes one definitive source.
Cause: Unknown
Status: UNRESOLVED
March 26 — Illinois: Small Earthquake Produces Sudden Boom and Shaking
Residents around Lake in the Hills reported a sharp boom accompanied by ground movement.
Seismic data identified a small earthquake, solving what initially sounded to many witnesses like an unexplained explosion.
Cause: Earthquake
Status: CONFIRMED
April 2015 — Earth-Shaking Booms in New Jersey and Oklahoma
April 1 — Central New Jersey: Earth-Shaking Booms Across Mercer County
Residents across parts of central New Jersey reported sudden powerful booms accompanied by noticeable vibration.
Police and local authorities investigated reports, but the surviving record does not provide a definitive seismic, military or industrial explanation.
Cause: Unknown
Status: UNRESOLVED
April 8 — Guthrie, Oklahoma: M4.3 Earthquake Arrives With a Loud Roar
A magnitude 4.3 earthquake near Guthrie was widely felt and accompanied by descriptions of loud roaring or explosion-like sounds.
The immediate source of the boom was therefore not mysterious: it accompanied a shallow earthquake.
The event occurred within Oklahoma’s larger period of dramatically increased earthquake activity. For the science of wastewater-triggered earthquakes and other human-induced seismicity, see: Induced Seismicity & Man-Made Earthquakes Explained.
Immediate boom source: Earthquake
Regional context: Elevated Oklahoma seismicity / induced seismicity
Status: CONFIRMED
May 2015 — Michigan Earthquake Boom and a Finnish Fighter-Jet Shockwave
May 2 — Michigan: Rare M4.2 Earthquake Produces Explosion-Like Boom
A magnitude 4.2 earthquake struck southern Michigan near Galesburg and was felt across a broad region.
Witnesses reported both shaking and explosive booming, providing another clear example of a shallow earthquake being experienced acoustically as well as seismically.
Cause: Earthquake
Status: CONFIRMED
May 21 — Helsinki, Finland: Fighter Jet Breaks the Sound Barrier
A powerful boom startled residents around the Finnish capital region.
The Finnish Air Force confirmed that a Hornet fighter had exceeded the speed of sound during an operation, producing the shockwave.
Cause: Military aircraft sonic boom
Status: CONFIRMED
June 2015 — New Zealand’s Long-Distance Mystery Rumble
June 23 — New Zealand: Mystery Boom and Rumble Reported From Turakina to Waitōtara
Residents across a broad stretch of New Zealand’s lower North Island reported a powerful boom and rumbling sensation.
The reports extended from around Turakina toward Waitōtara, suggesting a source capable of being heard or felt over a substantial area.
No sufficiently documented earthquake, meteor, sonic boom or explosion conclusively accounts for the event in the surviving record.
Cause: Unknown
Status: UNRESOLVED
July 2015 — The Rhode Island Beach Explosion Mystery
July 11 — Rhode Island: Mystery Beach Blast Traced to Hydrogen Beneath the Sand
A bizarre blast at Salty Brine State Beach in Narragansett suddenly shook the ground and injured a beachgoer.
Investigators initially treated the incident as a possible explosion, but police and fire investigators found no bomb, explosive material or incendiary device.
Scientists from the University of Rhode Island’s Graduate School of Oceanography then examined the beach sediments.
Their investigation uncovered an unusual explanation.
Hydrogen gas had apparently accumulated beneath the beach sand as an abandoned copper cable left by the U.S. Coast Guard corroded underground. Researchers concluded that combustion of this hydrogen buildup was very likely responsible for the blast.
Cause: Combustion of accumulated hydrogen gas
Status: LIKELY / SCIENTIFICALLY RESOLVED
August 2015 — Meteor Booms Over Scandinavia
August 13 — Norway & Sweden: Large Meteor Disintegrates With Audible Booms
A bright meteor crossed the Scandinavian sky and was accompanied by reports of explosive sounds.
The combination of a well-observed fireball and delayed atmospheric noise strongly supports a meteor-generated shockwave.
Cause: Meteor / atmospheric shockwave
Status: LIKELY
September 2015 — The Delmarva Mystery Boom
September 22 — Delmarva: Powerful Mystery Boom Shakes Virginia and Maryland
A powerful thunder-like boom was reported across parts of the Delmarva Peninsula, with witnesses describing buildings and surroundings shaking.
A sonic boom from military aircraft was an obvious possibility.
However, officials at Naval Air Station Patuxent River reportedly said no aircraft from the facility were operating in the relevant area at the time.
NASA personnel also looked into possible explanations.
Without a confirmed earthquake, aircraft source or other documented explosion, the event remains one of the stronger unresolved boom cases
of 2015.
Cause: Unknown
Status: UNRESOLVED
October 2015 — Coastal Maine Mystery Booms and a Taurid Fireball
October 1 — Coastal Maine: Quake-Like Boom Shakes Kennebunk and Kennebunkport
Residents and businesses around Kennebunk and Kennebunkport contacted police after hearing a powerful booming sound.
Some witnesses reported that their houses shook.
Police and firefighters checked the affected areas but found no obvious source such as construction blasting or an explosion.
Cause: Unknown
Status: UNRESOLVED
October 31 — Poland: Taurid Fireball Produces Atmospheric Booms
A brilliant fireball associated with the Taurid meteor stream was observed over Poland around Halloween.
Reports of delayed booming were consistent with shockwaves generated as the object penetrated deeply into the atmosphere.
Cause: Meteor / atmospheric shockwave
Status: LIKELY
November 2015 — Repeated Canadian Booms, a Huge Fireball and Pennsylvania Mystery Shaking
October 27 & November 7 — Oakville, Ontario: Repeated Early-Morning Mystery Booms
Residents in several parts of Oakville reported powerful early-morning booms on separate dates.
The recurrence attracted particular attention because no clear earthquake, explosion or other source was publicly established.
Cause: Unknown
Status: UNRESOLVED
November 19 — Midwest & Southern United States: Huge Fireball Produces Loud Blast
A bright fireball was observed over a broad region of the United States, with reports extending across parts of Illinois, Indiana, Kentucky, Tennessee and neighboring states.
Witnesses also reported explosive sounds consistent with atmospheric shockwaves from the meteoroid.
Cause: Meteor / atmospheric shockwave
Status: LIKELY
November 28 — Schuylkill County, Pennsylvania: Mystery Boom Shakes Residents
Residents reported a sudden powerful boom accompanied by shaking.
Authorities investigated possibilities including blasting and an atmospheric event, but no sufficiently strong explanation emerged.
Cause: Unknown
Status: UNRESOLVED
What Caused the Mystery Booms of 2015?
The strongest 2015 reports make one point especially clear: similar-sounding booms can come from completely different physical processes.
| Cause | 2015 examples | Typical evidence |
|---|---|---|
| Meteors |
New Zealand, Florida, Kerala, Switzerland, Scandinavia, Poland, Midwest U.S. |
Visible fireball, delayed boom, atmospheric trajectory, eyewitness clusters or instrumental detection |
| Earthquakes | Plainfield, Winchester, Illinois, Guthrie, Michigan | Seismic detection plus coincident shaking and audible rumbling |
| Cryoseisms | Tennessee and other cold-weather reports | Rapid deep freeze, saturated ground, localized cracking and shaking |
| Sonic booms | Helsinki and other military-aircraft events | Supersonic aircraft activity, broad pressure-wave footprint, no corresponding earthquake |
| Unusual combustion | Salty Brine State Beach | Physical investigation, gas measurements and identifiable mechanism |
| Unresolved | Luzerne County, Hampton Roads, central New Jersey, Whanganui, Delmarva, Maine, Oakville, Schuylkill County | Credible reports but insufficient evidence to establish one source |
How Can a Meteor Make the Ground Shake?
Meteoroids enter Earth’s atmosphere at enormous speeds. Instead of moving air gently aside, a fast object generates a shockwave.
If the meteoroid penetrates deeply enough or fragments violently, that pressure wave can reach the ground strongly enough to rattle windows and buildings.
In exceptional cases, atmospheric shockwaves can even couple into the ground strongly enough to appear on seismic instruments.
The March 15 Swiss event is a spectacular example: people heard the rumbling while seismic stations across northeastern Switzerland recorded acoustic energy generated by the meteor.
Why Can Small Earthquakes Sound Like Explosions?
Magnitude alone does not determine how an earthquake feels or sounds. A very shallow earthquake close to a populated area can create abrupt, high-frequency motion that witnesses describe as a crack, cannon shot, explosion or thunderclap.
Buildings, soil and rock near the surface can also convert part of the seismic energy into audible vibrations.
Plainfield, Guthrie and Michigan all demonstrate how an apparent mystery boom can turn out to be a small or moderate earthquake.
Where Does Induced Seismicity Fit Into the 2015 Boom Record?
Oklahoma and the Dallas–Fort Worth region were experiencing unusually high earthquake activity during this period.
Research has shown that large increases in seismicity in parts of the central United States were associated with the disposal of wastewater into deep underground formations.
That does not mean every audible boom or every individual earthquake can automatically be assigned to a particular injection well. The immediate source of an earthquake boom is still the earthquake itself.
For the broader mechanism, evidence and important case studies, see: Induced Seismicity & Man-Made Earthquakes Explained.
What Made the Rhode Island Beach Explosion So Unusual?
The Salty Brine incident shows why not every mystery boom fits familiar categories such as meteors, earthquakes or aircraft.
Investigators initially found no explosive device. Scientific sampling later pointed instead to hydrogen accumulating beneath the sand as an abandoned copper cable corroded.
The episode moved from apparent unexplained explosion to a rare interaction between chemistry, buried infrastructure and coastal sediment.
How This 2015 Mystery Boom Archive Was Rebuilt
Strange Sounds originally reported a much larger number of individual boom stories during 2015.
This archive is deliberately more selective.
Events are retained when they:
- document a meaningful natural or atmospheric phenomenon;
- show how an apparent mystery was scientifically resolved;
- have unusually strong eyewitness or instrumental evidence;
- represent a credible unresolved regional event; or
- help distinguish between commonly confused boom mechanisms.
Generic monthly compilations, ordinary fireworks, routine military noise advisories, known industrial accidents, infrastructure failures and poorly sourced internet claims are not treated as individual mystery-boom cases in the rebuilt timeline.
Classification prioritizes seismic records, meteor networks, government agencies, military statements, scientific investigations and credible contemporary local reporting.
Unresolved does not mean paranormal, extraordinary or inexplicable. It simply means the surviving evidence is insufficient to reliably identify the source.
Mystery Booms 2015 — Frequently Asked Questions
What caused the mystery booms of 2015?
There was no single cause. The strongest documented cases involved meteors, shallow earthquakes, frost quakes, sonic booms, military activity and unusual combustion events. Several credible reports remain unresolved.
Did meteors really cause house-shaking booms in 2015?
Yes. The February 21 northern Florida fireball generated numerous reports of delayed sonic booms that rattled windows and houses. Large meteoroids moving hypersonically through the atmosphere can generate powerful shockwaves before fragmenting or decelerating.
Was a meteor boom recorded by seismometers in Switzerland?
Yes. On March 15, 2015, seismic stations across northeastern Switzerland recorded sound waves generated by a bright meteor. The signals were detected over several minutes while witnesses also reported audible rumbling.
What caused the 2015 Rhode Island beach explosion?
Rhode Island and University of Rhode Island investigators concluded that combustion of accumulated hydrogen gas was very likely responsible. The hydrogen appears to have formed during corrosion of an abandoned copper cable buried beneath the beach sand.
Did earthquakes cause some of the 2015 mystery booms?
Yes. Earthquakes in Connecticut, Oklahoma, Illinois, Michigan and the United Kingdom were associated with audible booms, cracking or rumbling. Small shallow earthquakes can sometimes sound surprisingly explosive.
Were Oklahoma’s 2015 earthquakes related to induced seismicity?
Oklahoma’s broader increase in earthquake activity during this period was strongly associated with deep wastewater disposal. However, regional induced seismicity should not be interpreted as proof that every individual earthquake or boom was caused by a particular injection operation.
What caused the September 2015 Delmarva mystery boom?
No definitive source was established. Residents reported a powerful thunder-like boom and shaking, while a military-aircraft explanation was investigated but not confirmed. The event remains unresolved in the surviving record.
What does “unresolved” mean in this archive?
It means there is credible evidence that the reported event occurred, but insufficient evidence remains to identify its source with reasonable confidence. It does not imply an extraordinary or unknown physical phenomenon.
Did We Miss a Major 2015 Mystery Boom?
If you witnessed an important unexplained boom in 2015 that belongs in this historical archive, include the date, approximate time, location, weather, whether the ground or windows shook, whether a flash was visible, and any surviving video or contemporary news coverage.
