These fascinating science facts prove that reality is often stranger—and a lot more interesting—than fiction
25 Amazing Science Facts That Are Weird, Wild and True
Updated on Feb. 27, 2025
The human stomach can dissolve razor blades
Talk about a bizarre feature of the human body: If you happened to swallow a razor blade, your stomach acid would dissolve it. Acids are ranked on a scale from zero to 14—the lower the pH level, the stronger the acid. Human stomach acid typically has a pH of 1 to 2, which is incredibly strong. In a study published in the journal Gastrointestinal Endoscopy, scientists discovered that the “thickened back of a single-edged blade” dissolved after two hours of immersion in stomach acid. That said, we wouldn’t recommend swallowing one. Dissolvable or not, razor blades are still dangerously sharp.
A laser can get trapped in water
A cool thing known as “total internal reflection” happens when you point a laser beam at a jet of flowing water. To demonstrate this phenomenon, scientists from Harvard University positioned a laser on one side of a clear tank of water. On the other side, the water flowed through a hole and into a bucket. The heavier particles in the water slowed the laser’s light, effectively “trapping” the laser beam in the water. That’s why, when the light hit the flowing stream, it looked like a red waterfall. Even as the water flow was gradually decreased, the laser beam remained contained inside the jet until it eventually disappeared when the water was turned off completely.
Earth’s oxygen is produced by the ocean
Have you ever stopped to think about where oxygen comes from? Your first thought may be of a rainforest, but here’s a cool science fact for you: We can thank plant-based marine organisms for about half of the Earth’s fresh air, according to the National Oceanic Service. Luckily, this isn’t one of those ocean mysteries we’ll never solve. Scientists have learned that plankton, seaweed and other photosynthesizers produce more than half of the world’s oxygen.
Ocean animals use Earth’s magnetic field for orientation
Lost land animals aren’t the only ones who can find their way home; it turns out, some sea animals can too. But sea creatures use a completely different means of navigation. Here’s one of the coolest animal facts you’ll ever learn: According to the U.S. Geological Survey (USGS), some animals, like sea turtles and salmon, have the ability to sense the Earth’s magnetic field and can use this sense like a compass for navigation.
A cloud can weigh around a million pounds
Your childhood dreams of floating on a weightless cloud may not withstand this science fact: The average cumulus cloud can weigh up to a million pounds, according to the USGS. That’s even heavier than a Boeing 747 jet completely full of cargo and passengers. So why do they float? The moist air in clouds weighs less than the dry air below.
Soil is full of life
There are more microorganisms in a single teaspoon of soil than there are people on the planet. “Millions of species and billions of organisms—bacteria, algae, microscopic insects, earthworms, beetles, ants, mites, fungi and more—represent the greatest concentration of biomass anywhere on the planet,” says the U.S. Department of Agriculture.
Rats laugh when they’re tickled
These creatures are more dynamic than we think. Rats have the ability to “laugh” when tickled. A video from National Geographic based on a 2023 German study demonstrates that rats respond positively to tickling, and they even chase after the researcher’s hand in a playful manner.
Bananas are radioactive
Here’s a very strange history-of-food fact: Bananas contain potassium, and since potassium decays, that makes the yellow fruit slightly radioactive. But don’t worry—you’d need to eat a billion bananas (literally) in one sitting to die of banana-induced radiation poisoning, according to Joe Schwarcz, PhD, director of McGill University’s Office for Science and Society.
Hot water freezes faster than cold water
This may seem counterintuitive, but it’s called the Mpemba effect, after a Tanzanian teenager in the 1960s who found that homemade ice cream froze faster when it went into the freezer right after the mixture was boiled, and therefore still hot, instead of cooled down. Ever since, scientists have been trying to find an explanation for this phenomenon. Recent work has suggested it’s the result of the hot water being out of thermodynamic equilibrium. (That long science term refers to a system that’s stable and not undergoing changes to properties like temperature.) Other theories as to why this happens include the fact that cold water produces frost when freezing, which ironically insulates the water underneath, while hot water doesn’t.
There are more trees on Earth than stars in our galaxy
Here’s a cool space fact we bet you didn’t know: NASA experts believe there could be anywhere from 100 billion to 400 billion stars in the Milky Way. However, a 2015 paper published in the journal Nature estimated that the number of trees around the world is much higher: 3.04 trillion.
Humans have genes from other species
We like to think of humans as being superior to other living creatures, but the reality is that our genome consists of as many as 145 genes that have jumped from bacteria, fungi, other single-celled organisms and viruses, according to a study published in the journal Genome Biology. This process, called “horizontal gene transfer,” could change how we think about evolution.
But don’t worry—humans have a lot of DNA
Scientists have mapped the human genome and now know there are more than 3 billion base pairs of DNA in human genes and more than 25,000 genes in the human genome, according to an article in Nature. An entire copy of that genome exists in each of the 28 to 36 trillion cells in the adult human body.
It can rain diamonds on other planets
The atmospheres on Neptune, Uranus and Saturn have such extreme pressure that they can crystallize carbon atoms and turn them into diamonds. How do we know this science fact? Researchers were able to create the correct conditions in a lab to prove this occurs on Neptune and Uranus. Other researchers speculate that it may rain as much as 2.2 million pounds of diamonds on parts of Saturn every year.
There were roughly 2.5 billion T. rexes on Earth, but not all at the same time
Humans have been marveling at the size of the T. rex ever since they first put a full skeleton together. Now, thanks to research published in April 2021, scientists have a better idea of exactly how many of them once called Earth their (temporary) home. According to the team at the University of California, Berkeley, approximately 2.5 billion of these dinosaurs existed across more than 127,000 generations. They reached this estimate by figuring out what age T. rexes lived to, taking into account the dinosaur’s body size, sexual maturity and energy needs.
Water can exist in three states at once
This is called the triple boil—or triple point—and it is a specific temperature and pressure at which a material can exist as a gas, a liquid and a solid simultaneously. The triple point, which is also the only situation in which all three states of matter can coexist, is different for every material, according to the University of California, Santa Cruz. Water reaches its triple point at just above freezing (0.1 degree Celsius) and at a pressure of 0.006 atm (units of pressure).
Helium can work against gravity
When liquid helium is cooled to extreme temperatures, just a few degrees away from its boiling point (-460 degrees Fahrenheit), it turns into a superfluid, meaning it can flow without friction, Scientific American reports. It can climb up and over the sides of a glass, and it can leak through molecule-thin cracks in a container.
Another interesting science fact about helium: While it’s the second most abundant element in the universe, it can be harmful to the human body, according to an article in the journal Injury Prevention. So as funny as it may be to suck down some helium and hear your high-pitched voice, it’s best to keep birthday balloons out of your mouth.
Solar flares are more powerful than bombs
Sudden explosions from the sun, called solar flares, release energy equivalent to a billion hydrogen bombs, according to NASA. It’s a good thing Earth’s atmosphere protects us from their radiation! Though we’re safe on Earth during solar flares, we may experience blackouts and power outages from the disturbance they cause in Earth’s magnetic field.
It’s impossible to burp in space
When you burp on Earth, gravity keeps down the solids and liquids from the food you just ate, so only the gas escapes from your mouth. In the absence of gravity, the gas cannot separate from the liquids and solids, so burping essentially turns into throwing up a little in your mouth.
Plastic can end up as vanilla flavoring
Researchers have figured out how to transform plastic bottles into vanilla flavoring with genetically engineered bacteria, according to a 2021 study published in the journal Green Chemistry. The authors of the study explain that the demand for vanillin (the primary flavor component of vanilla) is “growing rapidly,” given that it’s found in a wide variety of food, cosmetics, pharmaceuticals, cleaning products and herbicides. But don’t expect to be eating plastic-bottle-flavored ice cream any time soon: This research demonstrated only that the conversion is possible—not that it is safe for human consumption.
About half of your body’s cells are bacteria
Experts estimate that the human body consists of 39 trillion bacteria and 30 trillion human cells—a roughly 1:1.3 ratio. But because bacteria are so small, they make up about only 1% to 3% of our body mass. In the past, researchers thought we were much more bacteria than human, with a ratio of 10:1.
Men are more likely to be colorblind than women
Guys have a greater likelihood of colorblindness, and it has to do with genetics. The genes responsible for the most common type of colorblindness are found on the X chromosome, the National Eye Institute explains. Even if women have the colorblindness genes on one of their two X chromosomes, a properly functioning gene on the other one makes up for that loss and allows them to see color. If men inherit the gene on their only X chromosome, they’ll be colorblind
We have no idea what most of the universe looks like
About 96% of the universe is made up of dark matter and dark energy, which are undetectable to humans. Scientists believe this is because the particles that make up these substances don’t interact with regular matter or light. So on the list of baffling mysteries about the universe, we can add “most of it.”
Bats don’t get sick from most viruses
And yup, that includes coronaviruses. Bats can, of course, contract and spread viruses, but according to research, they also have plenty of genes responsible for antiviral activity, keeping them out of harm’s way. Virologists have long been interested in bats because they carry rabies, says Thomas Kepler, PhD, a professor of microbiology at Boston University. But while bats occasionally get sick from rabies, they rarely die from it.
Beer is twice as fizzy as Champagne
If someone asks for a glass of bubbly, you won’t pour them a Guinness. But maybe you should. Scientists have determined that as far as bubbles go, beer is tops. While one flute of Champagne produces about 1 million bubbles, a half-pint of beer can create up to 2 million, according to a 2021 study published in the journal ACS Omega.
So why does this matter? More bubbles result in a more intense flavor. Of course, that’s not to say that beer and Champagne are in any way comparable to each other in taste—but they both contain carbon dioxide, which creates bubbles when you open a bottle and pour the liquid out.
Humans are capable of producing venom
Did you know we’re closer to cobras than you might think? Believe it or not, while humans do not currently produce venom, technically, we could. In fact, all reptiles and mammals have that capability, according to an article published in the journal Proceedings of the National Academy of Sciences. Basically, we have all the tools we need, and it’s up to evolution to get us there. We told you: These fun science facts are pretty amazing!
Additional reporting by Claire Nowak.
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Sources:
- NASA
- Science.gov
- Science Direct
- Nature
- McGill University: “Is it true that bananas are radioactive?
- Cell: “The Egyptian Rousette Genome Reveals Unexpected Features of Bat Antiviral Immunity”
