7 Unsolved Scientific Mysteries

There is a lengthy list of everyday occurrences that science still can't explain—along with several more bizarre mysteries that leave scientists puzzled, spanning disciplines from weather science to healthcare. Here are a few of them, drawn from an episode of The List Show on YouTube.

1. Why Some Individuals Wake Up from a Coma Speaking a Foreign Language

In April 2010, a young girl in Croatia awoke from an unexplained 24-hour coma, bringing joy to her family. However, something unusual happened: The 13-year-old could no longer speak Croatian to her parents. Despite understanding the language, she could only respond in fluent German, a language she had only recently started learning in school. She needed a translator to communicate with her family, and doctors were left baffled.

The case of this mysterious Croatian-German language switch isn't the only instance of brain injuries triggering unexplained language phenomena. In 2013, an Australian man emerged from a car accident speaking flawless Mandarin. In 2016, a teenager from Atlanta woke from a coma speaking perfect Spanish, struggling to speak his native English, to the point where he would have seizures whenever he tried.

Doctors and scientists can't fully explain these occurrences. The study of language development in the brain is an evolving field; experts generally assume that it's significant that all the cases mentioned above had some prior exposure to their new language, but the reasons behind why this phenomenon affects certain individuals so profoundly remain unclear.

2. What Triggered the Tunguska Event?

On June 30, 1908, a powerful explosion devastated a forest in Siberia near the Podkamennaya Tunguska River. A fireball, thought to be as large as 100 meters across, erupted in the sky, leveling around 80 million trees and killing hundreds of reindeer. The explosion's intensity was such that people in the nearby town, about 35 miles away, could feel its heat. One eyewitness described the event:

“The sky was split in two, and high above the forest the whole northern part of the sky appeared covered with fire … At that moment there was a band in the sky and a mighty crash … The crash was followed by a noise like stones falling from the sky, or of guns firing.”

In total, the explosion, now known as the Tunguska Event, is believed to have released roughly 185 times the energy of the atomic bomb dropped on Hiroshima.

Given the scale and intensity of this event, one would expect the cause to be clear. Yet, over a century later, scientists have yet to pinpoint the exact source. Initially, a meteoroid was considered the most likely cause. However, there was no impact crater, and few traces of an extraterrestrial object were found in the area. Some researchers later proposed it was a comet entering the atmosphere, as comets are primarily composed of ice and wouldn't leave behind clear rock fragments.

In 1958, an expedition to the site uncovered some promising globules that suggested a meteoritic origin. This could have solved the Tunguska riddle, but doubts remained. A 1973 paper proposed that a black hole had collided with Earth, triggering the explosion, but this theory was swiftly refuted. Later studies seem to support the idea of a meteoric explosion, though no definitive answer has been reached, and alternative theories, such as UFO crashes or nuclear blasts, still persist.

3. The Formation of the Patom Crater

The Tunguska Event isn't the only unexplained phenomenon in Siberia. In the Irkutsk region, another baffling site hides among the trees: the Patom Crater, also known as the Fire Eagle Nest. This large rock formation in southeastern Siberia is roughly 520 feet in diameter and rises about 130 feet in height, complete with a ring-shaped crown. Discovered in 1949 by geologist Vadim Kolpakov, it's believed to be around 350 years old.

The area is inhabited by the Yakuts, a Turkic people who have lived there for generations. According to Yakut folklore, the crater is a cursed location, feared by even the local deer. When Kolpakov first came upon it, he remarked, “From a distance it looked like a mine-shaft slagheap, only whitish. I even thought, 'Where are the people?' There were no labor camps in the area. Unless a very, very secret one?”

As the Tomsk Science Center (with help from Google Translate) reports, Kolpakov added, “But then I would not have been sent to geo-prospect this area, but, on the contrary, would have been advised to stay away from here. My second thought was an archaeological artifact. But the local Evenks and Yakuts, with my respect for them, are not the ancient Egyptians. They could not build stone pyramids, and didn’t have the human resources nor the necessary scientific knowledge.”

Much like the Tunguska Event, scientists initially speculated that the crater was caused by some form of extraterrestrial impact. However, some theorists suggest that it may have been caused by natural gas escaping through the Earth's surface. The debate surrounding its origins has been so intense in the geological community that a 2010 conference was held, named the Patom Crater Conference. The consensus was that the crater was not caused by a meteorite, but rather by some geological process, though this remains an educated guess for now.

4. How The Placebo Effect Works

In drug testing, scientists often compare a new medication to a placebo, like a sugar pill, to see if the drug is effective. For a drug to be considered effective, it must show better results than the placebo. However, an intriguing phenomenon occurs where placebos themselves seem to bring about changes in the test subjects, despite having no physiological basis for such changes. This measurable, albeit 'fake,' effect is known as the placebo effect.

The concept of the placebo effect has existed since at least the 18th century, yet scientists still don’t fully grasp it. What is understood is that the brain can trigger complex neurobiological responses simply because it expects results. For instance, the brain might release endorphins or dopamine if it believes it's been given an antidepressant. But that doesn't explain why this happens. Researchers at Harvard have been exploring both the positive and negative aspects of the placebo effect, treating it as a holistic experience. Professor Ted Kaptchuk explains it as follows:

"When you look at these studies that compare drugs with placebos, there is the entire environmental and ritual factor at work. You have to go to a clinic at certain times and be examined by medical professionals in white coats. You receive all kinds of exotic pills and undergo strange procedures. All this can have a profound impact on how the body perceives symptoms because you feel you are getting attention and care."

Despite these insights, the placebo effect remains puzzling. It’s still unclear why it doesn’t always work or why it’s more effective for certain people or situations. For now, it remains one of the many fascinating and enigmatic traits of the human brain.

5. How Morning Glory Clouds Form

While we, as a species, have made great strides in understanding weather—knowing what causes it, how to predict it, and when it’s a good conversation starter on a date—there’s one phenomenon that still puzzles us: morning glory clouds. These striking formations seem straight out of a fantasy novel.

Although reports of these impressive roll clouds have emerged from all over the world, the most reliable sightings occur near Burketown, Australia. Under very specific conditions, these clouds can stretch up to 600 miles in length. Each October, tourists, including many hang gliders, flock to Burketown hoping to witness this awe-inspiring sight.

Despite having a basic understanding of the conditions like specific humidity, sea breeze patterns, and mesoscale circulations that typically precede the formation of morning glory clouds, scientists still can’t explain why they are so distinctive and almost exclusively seen in one part of Australia. The mystery persists, likely because the necessary research into this visually stunning but scientifically insignificant phenomenon is underfunded.

6. What Caused Mary Reeser's Death

On July 2, 1951, Mary Reeser's landlord found a shocking scene when he visited her apartment: her charred remains. The only part of her body left unburned was one foot, still encased in a slipper. Intriguingly, the rest of the room showed no significant fire damage.

The FBI’s investigation suggested that Reeser had taken sleeping pills the previous night, and it was theorized that she may have fallen asleep while smoking a cigarette, possibly igniting her clothing. Their report also suggested that her body fat fueled the flames.

Skeptics found it hard to believe that a fire could reach such high temperatures while leaving the apartment largely undamaged. Cremation requires temperatures above 2000 degrees. Some speculated that spontaneous human combustion might explain the incident. This even led one professor from the University of Pennsylvania to propose that Mary was murdered, her body cremated, and then returned to her apartment. To this day, the true cause of her death remains unsolved.

7. The Origin of the Mysterious 'Upsweep' Sound

In the realm of unexplained phenomena, there is a whole spectrum of mysterious sounds. Some are heard from outer space, others from remote wilderness areas, and some are particularly chilling, emanating from the depths of the ocean. One of these strange sounds is the 'upsweep' sound.

The upsweep sound has been recorded since 1991, when the Pacific Marine Environmental Laboratory started capturing data from SOSUS, a network of underwater Soviet listening stations scattered across the globe. The sound consists of a long series of narrow-bandupsweeping noises, each lasting several seconds, as reported by the lab. If you’re curious about what it sounds like, you can listen to it yourself above.

The sound is believed to originate from an area located roughly halfway between Australia and South America. Interestingly, the upsweep sound varies with the seasons, peaking in both spring and autumn, though the reason for this fluctuation remains unknown. The most widely accepted explanation for the sound is volcanic activity.