In Victorian times, people would stop a house’s clocks at the time of an occupant’s death. Although this tradition continues somewhat today, there are some death clocks that weren’t stopped on purpose. Instead, they were broken by terrible circumstance, frozen forever to mark the last moments of disaster. These clocks are chilling mementos of past tragedies.

10 The Pirate’s Pocket Watch

On June 7, 1692, the town of Port Royal, Jamaica, was destroyed by a major earthquake. Shortly before noon, residents heard a thunderous cracking noise before feeling the earth shake violently and watching half their city slip into the sea. Three centuries later, historians began to explore the underwater ruins.

The most famous artifact recovered from the ruins was a pocket watch manufactured in the Netherlands around 1686. The hands on the watch were stopped at 11:43 AM, the exact time of the earthquake and the watch’s entrance into the sea. Although other records noting the time of the quake do exist, the discovery of the pocket watch was the first time that a stopped clock was used by archaeologists to date a disaster down to the minute.

9 Casey Jones’s Pocket Watch

Railroad enthusiasts know the story of John Luther “Casey” Jones, a train engineer who heroically died saving his passengers during a collision near Vaughn, Mississippi. While approaching the station at Vaughn, Jones and his signalman noticed something on the track ahead. They realized too late that it was the tail end of another train that was too long to fit its siding. The signalman leaped from the cab (on Jones’s orders), leaving Casey to his fate. A few seconds later, Jones’s train collided head-on with the other cars.

When Jones’s badly mangled body was pulled from the wreckage later that day, it was found that his pocket watch had stopped at 3:52 AM, the exact time of the impact. Although Jones died as a result of the crash, his actions ensured that he was the only fatality. No one else involved with either train suffered more than minor injuries.

8 The Titanic’s Mantel Clock

The story of the Titanic—the so-called “unsinkable” luxury ocean liner—is well-known. On the night of April 14, 1912, the ship struck an iceberg and ultimately sank into the North Atlantic during the early morning hours of April 15, taking approximately 1,500 people with it. Although there were many pocket watches and clocks retrieved from both victims and the ship itself, the most interesting one remains with the wreck.

This clock was located on the fireplace of the Straus suite, used by Macy’s founder Isidor Straus and his wife. Upon the dilapidated mantel, surrounded by sand and debris, sits a golden clock looking almost as new as it did the day it was made. Old pictures of the suite in its heyday show that the sinking did not affect the clock’s position at all. Its face, however, has seen some damage and is hard to read. The documentary Tony Robinson’s Titanic Adventure hypothesizes that the hands stopped either at 2:04 AM, when the last lifeboat was released, or 2:20 AM, the very minute the ship plunged beneath the waves.

7 John Taylor’s Pocket Watch

Joseph Smith, founder of the Church of Jesus Christ of Latter Day Saints, was killed on June 27, 1844, by a group of angry Illinois townspeople. After a long legal debacle that began with the destruction of an anti-Mormon newspaper’s printing press, Smith and a few other men waited in the Carthage, Illinois, jail for a trail. There, they saw a mob of around 200 men marching toward the building.

Although Smith was killed in the attack, his friend, John Taylor, miraculously survived. In the melee, Taylor tried to escape by jumping from the jail window but was pushed backward by the force of a gunshot from below. The shooter had been aiming for Taylor’s heart but instead hit his watch, which he kept in his left vest pocket. The hands of the watch were stopped at 5:16 PM, approximately the time that Joseph Smith breathed his last. Taylor later took his miracle watch to Salt Lake City, where he eventually became president of the Church of Jesus Christ of Latter Day Saints. The watch remains in the church’s archives to this day.

6 The Chernobyl Clock

In early morning hours of April 26, 1986, the Chernobyl nuclear power plant experienced a meltdown after a safety test went catastrophically wrong. In the ensuing hours, the power plant and nearby areas were blasted with radioactive energy, heat, and fire. In 2005, intrepid photographer Gerd Ludwig ventured into the radioactive ruins of the power plant for a 15-minute photography trip. Although all the photographs of ghostly control rooms and empty hallways are stunning, there was only one scene that Ludwig truly risked his life to capture.

Deep in the heart of the reactor, where the radiation is strongest, Ludwig ventured into a room hidden behind a steel door. In the few seconds allowed to him, he saw an old clock hanging on a wall, its hands stopped at 1:23:58 AM, the exact time at which the reactor exploded. The image of the clock spoke so much to Ludwig that he begged to be allowed a few brief seconds to photograph, in his words, “the time when on 26 April, 1986, in the building that housed Energy Block #4, time stood forever still.”

5 The Train Workers’ Clock

The entire world knows the story of September 11, 2001, in which the United States suffered the worst terrorist attack in its history. Although the US has largely rebounded from the tragedy, 9/11 hasn’t been forgotten. Each plane crash site was made into a memorial, with the largest and most elaborate filling the footprint of the Twin Towers in New York City.

In 2005, the Ground Zero Museum Workshop opened in New York to honor the dead and remind the living of that terrible day. One of the featured items in the museum is a clock found in the wreckage, its hands pointing to 10:02:14 AM, when the south tower collapsed. The clock was discovered in a break room used by local train workers alongside the remnants of their weight lifting bench.

4 The Photographer’s Pocket Watch

On August 6, 1945, the future of warfare was changed forever. Whether truly merited or not, US military leaders decided to destroy the city of Hiroshima, Japan, with the ace they’d secretly been building: the atomic bomb. Roughly 100,000 people were killed in the attack, and everything within a 1.6-kilometer (1 mi) radius was completely turned to rubble.

In the aftermath of the bombing, 19-year-old Shinji Mikamo returned to Hiroshima to dig through the ruins of his family home. There, he found his grandfather’s golden pocket watch, which had originally been given as payment for serving as an imperial photographer. Even though the watch’s hands had been blown off, the heat of the blast had seared the time of the bombing onto the metal below, leaving the clock to always read 8:15 AM. Shinji donated the watch to the Hiroshima Peace Memorial Museum in 1955 and then to a museum in the United Nations Headquarters in New York. Unfortunately, the watch disappeared in 1989 and has not been seen since.

3 The Murrah Building Clock

Masterminded by two criminals who were disgruntled with the government, the bombing of the Alfred P. Murrah Federal Building in Oklahoma City, Oklahoma, was the deadliest terrorist attack in the US before 9/11. On the morning of April 19, 1995, a moving truck loaded with explosives detonated outside the building, killing 168 people (19 of whom were children under the age of six) and injuring more than 650 others. Three months later, the remains of the Murrah building were demolished so that a memorial and museum could be built on the grounds.

The idea of stopped time is heavily integrated into both the memorial and the museum. Two large structures known as the Gates of Time flank the entrances of the outdoor memorial, each inscribed with a time stamp of significance. The eastern gate reads “9:01,” which represents “the last moments of peace” before the blast. Its parallel, the western gate, reads “9:03,” called “the first moments of recovery.” Enshrined in the museum, however, is a memento that marks the exact time of the blast: a clock poised at 9:02 AM.

2 Oppau Church Clocks

Oppau (now incorporated into the city of Ludwigshafen) was a small town located in Southwestern Germany. Oppau’s BASF chemical plant was responsible for the production of ammonium nitrate fertilizer, which it stored in a large silo alongside another chemical. Unfortunately, these two chemicals had a habit of getting stuck together, a situation that was remedied with the use of dynamite charges. While this operation was dangerous, it was also commonplace.

However, Oppau’s luck ran out on September 21, 1921, when the fertilizer exploded. The huge blast left both the factory and town destroyed. What did survive were several clocks belonging to nearby churches. Every single one was found to have stopped at 7:33 AM, the exact time of the explosion.

1 The Tsunami Clock

While the Hawaiian islands are seen as a paradise by many, they still face the wrath of nature on occasion. The city of Hilo, located on the Big Island, has itself faced two major tsunamis in the last century, the second of which was on May 23, 1960. One of the area’s famous landmarks, a green clock located in the low-lying suburb of Waiakea Town, survived the first tsunami but was heavily damaged by the second. Its hands are stopped at 1:04 AM, the time at which the first massive waves hit the island.

The clock has been kept in this condition as a memorial to those who lost their lives and homes and still stands today. Waiakea Town no longer exists, its former lands having been replaced with public parks and green spaces.

The author is a Ph.D. student in agriculture who lives to read and learn.

Although they don’t hang out shingles reading “Consulting Detective” or “Private Eye,” scientists have occasionally solved mysteries associated with crimes. More often, though, they solve puzzles, some of which are centuries old, that are related to their own areas of largely academic expertise: the discovery of the causes of a medical condition, of bacterial locomotion, or of seemingly extraterrestrial radio signals.

Other times, they may figure out the solution to a vexing mathematical theorem, the fate of disappearing molecules, the reason that a computer model can’t seem to account for the apparent contradictions in the persistence of complex ecosystems, or the reason that particular architecture bears unlikely stains.

Other puzzles scientists have contended with—and ultimately solved—posed questions of identity: what the dinosaur with the two huge arms looked like, who painted Madonna of the Veil, and to whom the bones found in some Tennessee woods belonged.

Now that science has marked these mysteries “solved,” they’re even more intriguing than when they’d been only perplexing problems or puzzles.

10 Narcolepsy’s Cause

Before the cause of narcolepsy was discovered, the condition, which is marked by daytime sleepiness, the sudden onset of sleep, a loss of muscle tone, and possible hallucinations, was a mystery that left medical doctors at a loss to treat it effectively. Although narcolepsy is relatively uncommon, affecting approximately only 1 in 2,000 people, the chronic sleep disorder makes life difficult for those who experience it.

Since 1986, Stanford University’s Dr. Emmanuel Mignot, a geneticist, has been attempting to zero in on the gene that causes the condition. In 2022, he finally struck pay dirt, identifying the culprit as a control for a neurotransmitter called orexin, which promotes wakefulness and blocks REM (rapid-eye movement) sleep. His unrelenting, determined hunt for the responsible gene earned Mignot a share of the $3 million Breakthrough Prize, the other part of which has been awarded to Masashi Yanagisawa of Japan’s University of Tsukuba, who, separately, but at the same time as Mignot, discovered orexin.

Further work revealed that narcolepsy is an autoimmune disorder. The neurons that produce orexin are destroyed by the body’s own immune system. Now, when Mignot takes his narcoleptic dog Watson with him to the sleep clinic to help explain the disease to his younger patients, the scientist can deliver the good news that new treatments can be developed to treat the condition. Now, thanks to Mignot, this scientific mystery has been marked “solved!” As a result, before long, those with narcolepsy can, hopefully, look forward to a good night’s sleep and the better daytime functioning that results from such rest.^[1]

9 Bacterial Movement

For half a century, scientists wondered how bacteria got from point A to point B. Light microscopes couldn’t show how bacteria with flagella move at the level of individual atoms, so researchers turned to cryogenic electron microscopy (cryo-EM) and advanced computer modeling in their attempts to depict possibilities. However, as Edward Egelman of the University of Virginia’s Department of Biochemistry and Molecular Genetics points out, the computers’ scenarios were wrong.

Bacteria, it was understood, somehow push themselves ahead by coiling their flagella, their thread-like appendages, into rotating corkscrew-like propellers. How the bacteria accomplish this feat puzzled scientists since the flagella are made up of only protein. Now, this scientific mystery has been solved. It was found that the bacteria’s protein exists in 11 states, and an exact mixture of these states is responsible for the formation of the flagella’s corkscrew shape.^[2]

8 Peryton Origin

No astronomer could solve the puzzling mystery of the origin of the strange radio bursts that appeared to be extraterrestrial in nature. However, Emily Petroff, a doctoral student at the Swinburne University of Technology, solved the mystery. Known as perytons, the bursts resemble deep space signals, which, scientists thought, might have resulted from neutron stars becoming black holes.

The actual cause of the signals was much more mundane: Microwave ovens used by astronomers to heat up their pot noodles. The oven’s door had been opened before the timer ended, causing the appliance’s magnetrons to emit very brief bursts at the 1.4Hz frequency. These emissions are typical of fast extragalactic radio bursts, but they were not coming from beyond the Milky Way.^[3]

7 Fermat’s Last Theorem

Seventeenth-century mathematician Pierre de Fermat’s Last Theorem remained a mystery for three centuries. Presented in the form of a seemingly straightforward equation, the theorem states there are no whole number solutions to the equation xn + yn = zn when n is greater than 2. Intrigued by the mystery since his boyhood, Andrew Wiles studied intensely during the seven years he attended Princeton University before the answer came to him. It happened thanks to a method involving “modular forms, elliptical curves, and Galois representations.” The fact that such pursuits are likely to be unfamiliar to us isn’t surprising, as they mean nothing to the layman but everything to brainiacs trying to solve this problem.

For his troubles, the Oxford University professor was awarded the 2016 Abel Prize and $700,000 cash. He also achieved fame. As a representative of the Norwegian Academy of Science and Letters said, “Wiles is one of very few mathematicians—if not the only one—whose proof of a theorem has made international headline news.”^[4]

6 Disappearing Molecules

During ultracold chemistry research, Kang-Keun Ni, the Morris Kahn associate professor of chemistry and chemical biology and of physics at Harvard University, and her team lowered the temperature of two potassium-rubidium molecules to almost absolute zero. As a result, they prolonged the duration of the existence of the intermediate, the space where reactants transform into products, a million times longer than they live in higher-temperature regions. They extended it to about 360 nanoseconds, allowing them not only to observe the reactants’ transformation into a product but also to manipulate it using lasers. In the process, the team learned why ultracold molecules disappear when forced to react.

When trapped together in the laser light, the gas molecules bumped against each other as expected, but some simply disappeared—or seemed to. In reality, the disappearing molecules are believed to have transformed into new species when they collided. So rather than simply heading off in different directions because of the light that the team used during their experiments, the molecules deflected off their typical reaction path and into a new one.^[5]

5 Persistent Complex Ecosystems

Scientists use computer models for much the same reasons that filmmakers use special effects: either it is impossible or too dangerous to chart or shoot the real deal. A case in point: scientists struggle to identify ecosystem responses to environmental change. Sometimes, such models themselves introduce unexpected mysteries. One such enigma is the co-existence of divergent complex systems, such as jungles, deserts, and coral reefs, in which species coexist and interact with one another. The math says that the persistence of such systems is impossible; nature shows that it is not.

How to reconcile the math with the reality was a puzzle that stymied scientists until recently. According to the U.S. National Science Foundation, Stefano Allesina and Si Tang, both from the University of Chicago, solved that vexing modeling mystery by introducing a real-world variable that the modelmakers had omitted. Namely, it was the fact that, whether in the rainforest, the desert, the coral reef, or elsewhere, some species interaction takes the form of the eat-or-be-eaten relationships between predators and prey. The model designed by Oxford University’s Robert M. May omitted such behavior. Allesina and Tang added predation to the mix.

The results of this additional variable showed that the stability properties of complex ecological systems were determined by the type of interaction among species (predation, competition, mutualism) and the strength of those interactions. The researchers did so without using the supercomputers or other high-tech instruments that are so frequently at the core of current biological discoveries, employing nothing more than pen and paper. Their breakthrough came after finding a 1988 article on quantum physics that gave them the key to cracking the problem.^[6]

4 Deinocheirus Mirificus’s Appearance

It’s difficult, even for scientists, to solve a mystery when they have only a couple of the pieces of a puzzle, and that’s all paleontologists had of a dinosaur’s fossilized skeleton. All the bones but two—a pair of massive arms—were missing. Scientists tried to guess the appearance of the rest of the Deinocheirus mirificus. It was thought it might have resembled a T. rex-type predator. On the other hand, it might have looked more like a giant sloth-like climber that used its arms to dangle from trees. After a complete skeleton of the mystery beast was finally discovered in 2014, lead researcher Yuong-Nam Lee of South Korea’s Institute of Geoscience and Mineral Resources said it was found to have been “weird beyond our imagination.”

The creature was huge, with a beak, a humped back, and giant, hoofed feet. It was 36 feet (11 meters) long and weighed six tons with an elongated head, a duck-like beak, a large humped sail on its back, short and stumpy legs, and big hooved feet. It moved slowly and inhabited boggy wetlands, dining on plants and fish. It possibly used its long forearms and giant claws to dig and gather herbaceous plants in freshwater habitats. Professor John Hutchinson, a paleontologist with the UK’s Royal Veterinary College, said, “It really is shocking to see how many weird features it has. It changes our view of what kind of forms dinosaurs can take.”^[7]

3 Botticelli Painting Authenticity

To collectors and museums, authenticity means big bucks in the art world. However, forgery is more prevalent than may be thought. One of the questions of authenticity in the twentieth century involved Madonna of the Veil, allegedly painted by the Italian master Sandro Botticelli.

Around the time of World War II, art experts began to harbor suspicions about the painting. Electron-beaming EDX analysis on the painting revealed it contained opaque chromium oxide green, a pigment that didn’t become widely available until 1862, some 350 years after Botticelli died. The painting’s frame must have been old, though, since its wood bore wormholes. The holes, however, turned out to be the work of a drill rather than of wood-hungry beetle larvae. Ultimately, the supposed masterpiece was exposed as the work of Umberto Giunti, an Italian forger at work during the 1920s. Science had solved the mystery of the bogus Botticelli.^[8]

9 Cold Case

Years of uncertainty about what happened to a missing person is frustrating, to say the least. It is also quite an ordeal for those without a clue about their loved one’s fate. The distress of those who knew fifteen-year-old Tracy Sue Walker, who disappeared in Lafayette, Indiana, in 1978, did not come to an end until years after she went missing. This happened when, four hundred miles from Lafayette, some of her bones, including her skull and teeth, were found in the woods of Campbell County, Tennessee, along with a necklace. However, the forensics of the day weren’t able to positively identify the remains as Tracy’s. It wasn’t until 2022 that the Tennessee Bureau of Investigation was able to ID the remains of the missing female.

Thanks to new techniques that allowed the creation of a DNA profile from the scantest remaining material, despite long-term environmental contamination, digital information could be uploaded to genealogical databases. As a result, a potential relative was located in Indiana, as were possible family members in Lafayette who confirmed that Tracy had disappeared from the area. The University of North Texas Center for Human Identification in Fort Worth was able to confirm that the remains that had been found in the Tennessee woods were, in fact, those of Walker. At last, her family now knows where, if not how, their missing loved one died.^[9]

1 Alhambra’s Purple Stains

The “purplish smudges” on the “gilded plasterwork” of the Alhambra, the Islamic fortress-palace monument in Granada, Spain, mystified experts. Specifically, they wondered what had caused them. Scientists knew what they were not. They weren’t effects of added pigment. A bit of library research turned up a possible culprit: gold particles. Examining the purple stains under an electron microscope verified the researchers’ hypothesis. Now all that remained of the mystery was how the gold particles had been produced.

The centuries-old age of the Alhambra made it difficult to pinpoint the exact process by which the gold particles were created, but the location in which they were discovered offered a clue. The purple stains of the Alhambra are not everywhere, only in some of the gilded portions of the monument that are outdoors or exposed to humidity and salt from the spray of the Mediterranean Sea, which is only 31 MILES (50 kilometers) away. These facts led researchers to finally solve the mystery of Alhambra’s purple stains. They are due to a mixture of elements: the tin sheets behind the gold leaf, the humidity of the environment, and the aerosols that the wind brings from the Mediterranean, which dissolved the gold in the sheets. Experts marked another scientific mystery “solved!”^[10]