Original photo by Ben Iwara/ Unsplash+

The average adult blinks about 15 times a minute, whether to lubricate the eyes, clear unwanted irritants, or refocus attention. Babies, on the other hand, blink far less often — only two to three blinks per minute on average. So, why do infants blink less than adults? The answer may lie with our brain’s dopamine levels, which control human blinking. Scientists initially made connections between this feel-good neurotransmitter and blinking because people with schizophrenia, who usually have excess dopamine production, may blink more frequently. The inverse is also true — Parkinson’s disease, caused by damaged dopamine-producing neurons, makes people blink less often. So a baby’s infrequent blinking may be a clue about how the brain forms after we’re born, showing that a baby’s dopamine system is likely still forming and thus impacting blinking frequency. 

Birds blink just like humans.

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Like humans, birds have an upper and lower eyelid — but they also possess a third eyelid, known as a nictitating membrane. This transparent nictitating membrane sweeps sideways across the cornea, keeping it clean and moist. As a result, most birds don’t blink like humans do.

However, dopamine production is only one piece of the mystery. Scientists also theorize that because a baby’s eyes are small, they likely require less lubrication than adult peepers. Babies may also blink less often because it’s actually pretty demanding to be a baby, requiring more active attention to gather the necessary visual information for survival (and thus leaving less energy for blinking). So while babies may seem like pint-sized layabouts, they’re actually putting in a lot of work to become functioning and frequently blinking members of society. 

Numbers Don't Lie

Numbers Don't Lie

Years ago animals evolved the ability to blink
375 million
Average number of times a person blinks in a single day
16,800
Percentage of waking hours humans spend blinking
10
Number of studio albums by rock band Blink-182
8

Babies perceive the color ______ first.

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Babies perceive the color red first.

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Blinking neurologically resets our brain.

Blinking is vitally important for the healthy upkeep of our eyes, but it also gives our brain a much-needed rest throughout the day. In 2012, scientists from the University of Osaka observed participants as they watched a television show by recording their blinks at 600 frames per second. When the TV scene changed or actors exited the frame, subjects would often blink. Scientists theorized that this blinking activated a “default mode network” causing sections of the brain associated with attention to temporarily shut down. This brief mental reprieve explains a variety of behaviors involved with blinking, including why humans tend to nictitate far more than mere lubrication requires. Blinking essentially allows the human brain to refocus, and this momentary suppression of attention — which also switches off the visual system — is why humans have little to no perception of blinking at all.

Darren Orf
Writer

Darren Orf lives in Portland, has a cat, and writes about all things science and climate. You can find his previous work at Popular Mechanics, Inverse, Gizmodo, and Paste, among others.

Original photo by Venimages/ Alamy Stock Photo

Since his 1938 debut in Action Comics No. 1, Superman has evolved into an even more powerful superhero than the original character. While he’s always been super strong and super fast, he didn’t initially have his now-famous ability to fly. You’ve probably heard the slogan “able to leap tall buildings in a single bound” — that comes from his ability to jump an eighth of a mile at a time, which is originally as close as he came to being able to fly.

Kryptonite was introduced on the Superman radio show before the comic books.

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Kryptonite became official Superman lore in 1943, five years after the character debuted. It was introduced on the “Adventures of Superman” radio show as a tool to incapacitate the character, which allowed the voice actors to take a break. It was later added to the comics in 1949.

The first implied instance of Superman taking flight was on an August 1939 cover of the British magazine Triumph, where the superhero appears to be flying into space. It was also hinted at in the second episode of The Adventures of Superman radio program in 1940. Then came artist Leo Nowak, who, assuming the hero had been given the power of flight, mistakenly drew Superman hovering above the ground in 1941’s Superman No. 10, which some now consider to be the first example of the character midflight. Funnily enough, Nowak was also the first to portray the villainous Lex Luthor as bald (earlier drawings depicted him as having red hair).

Superman officially gained the ability to fly in 1941’s The Mad Scientist, the first of 17 animated shorts from Fleischer Studios. The studio found it challenging to animate Superman’s leaping ability and asked DC Studios’ permission to make the character fly, which was easier to portray. (The request was granted.) In the comics, the first formal mention of this ability came in 1944’s Superman No. 30. While chasing a character named Mr. Mxyzptlk through the sky, Superman quips, “I thought I was the only one who could fly!!”

Numbers Don't Lie

Numbers Don't Lie

Cost of the most expensive Superman comic ever sold
$6 million
Top speed (in mph) of the Superman roller coaster at Six Flags New England
77
Movies in which Superman is portrayed by Christopher Reeve
4
Price paid by DC Comics for the exclusive rights to Superman
$130

Superman appeared in an episode of the beloved sitcom “______.”

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Superman appeared in an episode of the beloved sitcom “I Love Lucy.”

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Superman was originally conceived as a villain.

Superman wasn’t always the goody two-shoes we know him to be today; in fact, the original version was a villainous character. In January 1933, comic book writer Jerry Siegel published a short story titled “The Reign of the Superman” in an edition of Science Fiction. It centered around an evil supervillain with telepathic abilities who was dead set on world domination. The story also featured illustrations from Siegel’s friend and comic book artist Joe Shuster, but it wasn’t the smash hit they hoped it to be. In the wake of Adolf Hitler’s rise to power that same year, Siegel, who was Jewish, reimagined the “super man” as a force for good. The duo got to work on a new comic featuring the Superman character as a hero. The pair struggled in shopping around the idea until 1938, when DC Comics finally purchased the inaugural Superman story.

Bennett Kleinman
Staff Writer

Bennett Kleinman is a New York City-based staff writer for Inbox Studio, and previously contributed to television programs such as "Late Show With David Letterman" and "Impractical Jokers." Bennett is also a devoted New York Yankees and New Jersey Devils fan, and thinks plain seltzer is the best drink ever invented.

Original photo by Daniel Villalobos Oliver/ iStock

The internet is unfathomably vast, but it’s also quite small. In fact, a researcher in 2006 found that in physical terms, it only weighed about 50 grams — roughly the same as three large strawberries. That estimate was updated to 141 grams in 2018, and as the internet continues to grow exponentially, we can assume it’s well on its way to the equivalent of a whole crate of strawberries. What’s actually being weighed in that calculation are the electrons inside the computer servers that make the internet run. The weight of that energy is considerably heavier than that of the actual stored data on the internet itself, which in 2007 was measured as low as 0.2 millionths of an ounce — about the same as the smallest grain of sand you can imagine. There are at least 100 million internet servers in existence, which weigh quite a lot when combined.

Strawberries are berries.

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They actually belong to the rosaceae (rose) family and have been called a “false fruit” by botanists.

These are all estimations, of course. The internet is growing at a rapid pace, and any calculations of its size — whether in terms of the information contained therein or the actual mass of the infrastructure — could quickly become outdated. Even so, the disparity between how simultaneously big and tiny the web can seem by different measurements remains striking.

Numbers Don't Lie

Numbers Don't Lie

Tons of strawberries produced in the U.S. in 2023
1.4 million
Estimated gigawatts of electricity it takes to power the internet each year
84-143
Pounds of strawberries eaten per capita by Americans in 2021
6.7
Internet users in the world
5.45 billion

The internet doubles in size every ______ years.

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The internet doubles in size every five years.

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Each seed of a strawberry is its own fruit.

Despite the “false fruit” designation they’ve received from some botanists, strawberries are actually what’s called accessory fruits. This means the fleshy, bright-red pulp is derived from the plant’s receptacle (the thickened part of the plant’s stalk that connects to the flower), and the individual seeds are the actual fruit. As the average strawberry has about 200 seeds, that’s a lot of fruit per strawberry. The garden strawberry (as the common strawberry is known) is actually a hybrid of two different species, Fragaria virginiana (from North America) and Fragaria chiloensis (from Chile), and was first bred in Brittany, France, in the 1750s.

Interesting Facts
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Interesting Facts writers have been seen in Popular Mechanics, Mental Floss, A+E Networks, and more. They’re fascinated by history, science, food, culture, and the world around them.

Original photo by NurPhoto SRL/ Alamy Stock Photo

Civil rights icon Rosa Parks spent more than 40 years living in her home state of Alabama before moving to Detroit, Michigan, in 1957. There, she briefly resided in a house owned by her brother, located at 2672 S. Deacon Street. While there’s some debate over how long Parks lived there, what’s certain is she spent a great deal of time at the house with her family. Despite the house’s historic significance, however, it was set to be demolished by the city until Rhea McCauley — Parks’ niece — purchased the home from city officials in 2014 for $500. McCauley then gifted the home to artist Ryan Mendoza, and thus began its whirlwind adventure around the world.

Rosa Parks was the first woman to lie in state in the U.S. Capitol.

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In October 2005, Rosa Parks became the first woman to lie in honor in the rotunda of the U.S. Capitol, and only the second African American to earn the distinction. A statue of Parks was unveiled in the National Statuary Hall in 2013, the first full-scale statue of a Black American inside the U.S. Capitol.

After trying and failing to convince the city of Detroit to preserve the building, Mendoza dismantled the home and relocated it to his art studio in Berlin, Germany, where it was rebuilt. The house returned to the U.S. in 2018 as part of the Rosa Parks House Project, an art installation that honored the legendary activist. It was then briefly exhibited in the WaterFire Arts Center in Providence, Rhode Island, before it was sent back overseas to Europe. In 2020, the house found its way to Naples, Italy, where it was displayed in the courtyard of the Royal Palace of Naples for several months as part of an art exhibit. While the future status of the home is currently unclear, Mendoza has repeatedly expressed hope for it to permanently return to the United States and be converted into a national monument.

Numbers Don't Lie

Numbers Don't Lie

Fine imposed on Parks for refusing to give up her bus seat
$14
Length (in days) of the Montgomery bus boycott
381
Selling price of the Rosa Parks bus at a 2001 auction
$492,000
Year Rosa Parks received the Congressional Gold Medal
1999

Rosa Parks was a ______ by trade.

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Rosa Parks was a seamstress by trade.

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Claudette Colvin refused to give up her bus seat before Rosa Parks.

It’s impossible to deny the impact of Rosa Parks’ act of defiance, which acted as a major catalyst during the Civil Rights Movement. But she actually wasn’t the first Black woman to refuse to give up her bus seat in Montgomery, Alabama. Nine months earlier, on March 2, 1955, 15-year-old Claudette Colvin was riding a bus home from school with three other Black classmates when the driver demanded they move to make room for white passengers. While Colvin’s friends obliged, she insisted it was her constitutional right to stay, and she stood her ground until she was forcibly removed from the bus and arrested. The NAACP considered using this event to challenge extant segregation laws, but worried Colvin’s teen pregnancy could potentially attract negative attention. However, Colvin later served as a plaintiff in the 1956 court case Browder v. Gayle, which established that Montgomery’s segregated bus system was indeed unconstitutional. Several other women who had also refused to give up their bus seats in Montgomery between Colvin and Parks, including Aurelia S. Browder, Susie McDonald, and Mary Louise Smith, served as plaintiffs alongside Colvin.

Bennett Kleinman
Staff Writer

Bennett Kleinman is a New York City-based staff writer for Inbox Studio, and previously contributed to television programs such as "Late Show With David Letterman" and "Impractical Jokers." Bennett is also a devoted New York Yankees and New Jersey Devils fan, and thinks plain seltzer is the best drink ever invented.

Interesting Facts

No two humans smell exactly alike, because odor is a complex medley of aromatic influences that come from our environment, genes, and various secretions; all of these add up to what’s known as our volatile organic compound (VOC). Gender can also be a differentiating factor, as a 2023 study from Florida International University discovered. As part of the experiment, 30 self-described men and 30 self-described women grasped cotton balls for 10 minutes in hands that hadn’t been washed for at least an hour. Those cotton balls were then analyzed using gas chromatography and mass spectrometry to identify the individual chemicals that made up the various VOCs of the participants. Using a type of data analysis known as chemometrics, the researchers were able to identify the gender of the participant based on their hand odor with stunning 96.67% accuracy. In other words, men’s and women’s hands seem to produce different odors. 

The bacteria that make body odor are good for you.

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Most human sweat is essentially odorless salt water, but when skin bacteria eat proteins in our sweat, they produce odor. Yet many of these stinky types of skin bacteria actually protect us from eczema, as well as from dangerous infections such as MRSA.

Such a fact aligns with a variety of evidence that humans have subtle aromatic differences. Diseases have particular smells (acute diabetes smells like rotten apples, for example) and diet can also play a role. One study even discovered that single males smell differently than their partnered counterparts, mainly due to differences in testosterone levels. As for our hands, this subtle chemical fingerprint could one day inspire new tools for forensic scientists to analyze crime scenes. But for now, our fragrant hands remain primarily an aromatic oddity.

Numbers Don't Lie

Numbers Don't Lie

Value (in USD) of the worldwide hand sanitizer market as of 2023
$3 billion
Rough age (in years) of handprints left by children in Tibet, possibly the world’s oldest cave art
200,000
Position of the “thumbs up” in Adobe’s 2022 ranking of most popular emojis in the U.S.
2
Approximate number of bacteria found on an average young man
39 trillion

Only about ______ in 10 people are left-handed, though estimates vary.

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Only about one in 10 people are left-handed, though estimates vary.

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The evolution of the human hand begins with a 380 million-year-old fish.

Go back far enough in time, and all humans share the same fishy ancestor. Therefore, it’s not surprising that some scientists think that certain aspects of the human body still reflect our past life in the water. Hiccuping, for example, has been theorized as a leftover spasm from back when we sported gills, and humans (as well as most other animals) look distinctly fishlike when we’re embryos. Even features that seem uniquely human, such as our dexterous hands, may be evolutionary gifts from our water-dwelling ancestors. For decades, scientists believed that the evolutionary journey of the human hand began with tetrapods, otherwise known as our four-legged, terrestrial forebears. However, recent research found that an ancient fish known as Elpistostege watsoni, which lived during the Late Devonian period, evolved the digits and radial bones that eventually became our hands and feet. Scientists theorize that hands developed in these ancient fish as a way to support body weight, allowing the animals to perform “push-ups” in shallow water for gulping down fresh air. As hard as it may be to fathom that land-dwelling Homo sapiens actually has an aquatic origin story, it’s an ancient tale that’s etched into our very biology.

Darren Orf
Writer

Darren Orf lives in Portland, has a cat, and writes about all things science and climate. You can find his previous work at Popular Mechanics, Inverse, Gizmodo, and Paste, among others.

Original photo by Barisev Roman/ Shutterstock

Although the sky is blue throughout the year, it’s often a richer blue in the fall and winter, especially at latitudes farther from the equator. Why? Well, the answer has to do with both electromagnetism and the biology of the human eye. As a refresher: All visible colors are tied to some wavelength along the electromagnetic spectrum. When sunlight enters Earth’s atmosphere, gas and dust particles reflect the shorter wavelengths of visible light (such as blue) more than longer wavelengths (such as red). That — and the sensitivity of the human eye to the color blue — is why the sky appears as a cool sapphire.

Boston is considered the U.S.’s fall foliage capital.

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While New England attracts legions of leaf-peepers every autumn, it’s the northern city of Stowe, Vermont, that’s widely regarded as the best place to view fall foliage. Some 850,000 people visit the small town every year in the summer and fall.

However, as the seasons progress, one part of this equation changes: the sun’s position. As the sun gets lower and lower in the sky during its annual journey back toward the equator (and eventually the Tropic of Capricorn), the angle of the sun’s light hitting the atmosphere causes even more blue light to scatter, while red and green light decrease. That causes the sky to turn an even richer blue. These blue skies are especially easy to see in much of North America as cooler temperatures mean less moisture (and therefore fewer clouds), giving you an uninterrupted view of that deep azure atmosphere.

Numbers Don't Lie

Numbers Don't Lie

Year Irving Berlin wrote the song “Blue Skies”
1926
Max length (in nanometers) of the electromagnetic wavelength our eyes perceive as blue
495
Percentage of U.S. citizens who prefer the color blue — the most of any color — according to one survey
31
Year the phrase “blue devils” was first recorded; it eventually influenced the name of the “blues” genre
1756

The original name for the fall season was “______.”

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The original name for the fall season was “harvest.”

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When leaves change color, they’re revealing pigments that have been there all along.

The multihued splendor of fall foliage is one of the most indelible symbols of the season. Although this process is often described as leaves “changing color,” it might be better to say they’re showing off color that’s always been there. During the spring and summer, a tree’s leaves are green due to the busy work of photosynthesis, which produces the pigment chlorophyll. When trees prepare for the dark and cold months ahead, they stop producing chlorophyll, and as this green color recedes, pigments that have always been present in the leaves, such as carotenoids (orange and brown) and anthocyanins (red and purple), are finally able to shine through.

Darren Orf
Writer

Darren Orf lives in Portland, has a cat, and writes about all things science and climate. You can find his previous work at Popular Mechanics, Inverse, Gizmodo, and Paste, among others.

Interesting Facts

Cats certainly aren’t unknown in the world of physics. Isaac Newton had a cat named Spithead (and supposedly created a cat door for him), while Albert Einstein once said that only two things provided refuge from the misery of life: “music and cats.” Of course, the most famous example is Schrödinger’s cat, a thought experiment devised by Austrian physicist Erwin Schrödinger to explain the complexity of quantum superposition. But none of these cats, whether real or allegorical, has ever written an influential physics paper. That distinction belongs solely to F.D.C. Willard, a Siamese cat otherwise known as Chester.

The CIA tried using cyborg cats as spies in the 1960s.

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As part of Operation Acoustic Kitty, the CIA implanted a microphone and a radio transmitter inside a cat to spy on Cold War adversaries. But the project quickly hit a dead end, with a now-unclassified document stating the obvious problem: “Cats are not especially trainable.”

While it’s fun to imagine Jack H. Hetherington — the paper’s very human author — working alongside his cat to explore atomic behaviors at different temperatures, the reason for the feline’s inclusion was actually a matter of pronouns. Before submitting his paper for publication in the journal Physical Review Letters back in 1975, Hetherington noticed that he’d used the royal “we” throughout his work, and a colleague informed him that the journal only used such verbiage when a paper had multiple authors. Unwilling to go back and change the entire paper (these were typewriter days after all), Hetherington instead invited Chester, under the more official-sounding pseudonym F.D.C. Willard, to be his collaborator. Hetherington’s deception was baked right into the name: Felis Domesticus Chester Willard (Felis domesticus being the genus and species of the common house cat, and Willard being Chester’s father’s name). According to Hetherington, the journal’s editors didn’t find the feline contribution especially amusing, but time heals all wounds. In 1980, Willard even went on to become the sole “author” of a scientific paper in French. In 2014, Physical Review Letters granted free access to all cat-written physics papers as an April Fools’ Day joke.

Numbers Don't Lie

Numbers Don't Lie

Number of animals (including one cat named Simon) who’ve received Britain’s Dickin Medal for wartime animals
75
Estimated number of households in the U.S. that have a feline family member
46.5 million
Year Erwin Schrödinger devised the thought experiment “Schrödinger’s cat”
1935
Number of ship sinkings a cat nicknamed “Unsinkable Sam” survived during World War II
3

The Norse goddess of fertility ______ rode in a chariot pulled by two tomcats.

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The Norse goddess of fertility Freyja rode in a chariot pulled by two tomcats.

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In 1963, France sent the world’s first (and still only) cat to space.

On October 18, 1963, a Parisian stray cat named Félicette began her spacefaring journey aboard a French rocket launched from the Sahara Desert. The black-and-white cat was chosen from a crew of 14 cats trained for the mission, and she quickly traveled from the surface nearly 100 miles skyward, far beyond the Kármán line that separates Earth’s atmosphere and outer space. After becoming the first cat to escape the gravitational embrace of Earth, Félicette parachuted back to the planet’s surface. There, she was recovered by helicopter (still very much alive); the entire trip lasted only 15 minutes. Today, few people know about Félicette’s epic journey, as it’s often overshadowed by the 1957 flight of the Soviet space dog Laika. To commemorate the one and only astrocat’s achievements, a 2017 Kickstarter campaign raised £43,323 to create a memorial to Félicette. Today, the bronze statue — featuring Félicette perched atop the globe — resides at the International Space University in Strasbourg, France.

Darren Orf
Writer

Darren Orf lives in Portland, has a cat, and writes about all things science and climate. You can find his previous work at Popular Mechanics, Inverse, Gizmodo, and Paste, among others.

Original photo by zagi89/ iStock

On average, twins are delivered just a few minutes apart — but this isn’t always the case. In 1996, for instance, a Maryland woman named Lesa West gave birth to fraternal twins over a span of 90 days. On January 1 of that year, Lesa and her partner David welcomed their daughter Molly into the world, who was born premature. After Molly’s birth, doctors were able to stop Lesa’s contractions so she could carry the other baby to full term. Three months later, on March 30, Lesa finally gave birth to little Benjamin, setting an all-time record for the longest gap between the birth of two twins.

Four babies were born at a Rolling Stones concert in 1969.

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On December 6, 1969, the Rolling Stones headlined the Altamont Free Concert in California, alongside Santana, Jefferson Airplane, and others. According to the American Red Cross, four concertgoers gave birth during the six-hour spectacle, which was attended by roughly 300,000 people.

When it comes to triplets, the longest recorded interval between births is shorter, albeit still quite substantial. On September 20, 2004, Kara McBurney of Missouri gave birth prematurely to her son Lorne. Kara then remained in the hospital for weeks until she delivered her son Sullivan 17 days, 18 hours, and 55 minutes later, and her son Isaac shortly after. There have also been two recorded instances of women delivering quadruplets over the span of several days. In general, twins are delivered earlier than single-baby pregnancies, and less than one in every two twin pregnancies lasts beyond 37 weeks. Once the first baby is delivered, it’s preferable to deliver the next child in about 15 minutes to avoid complications, and the majority of twins are delivered within 30 minutes. It doesn’t always take that long, however: The shortest recorded time between twin births was a Canadian woman named Amanda Dorris, whose twins were born just 22.976 seconds apart on April 6, 2017.

Numbers Don't Lie

Numbers Don't Lie

Average birth rate of twins per 1,000 live births in the U.S. (as of 2022)
31.2
Most surviving children ever delivered during a single birth
9
Weight (in pounds) of the heaviest baby ever born
22
Percentage of twins who are said to share their own “secret language”
~40%

Babies are born with around 300 ______.

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Babies are born with around 300 bones.

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African elephants have the longest gestation period of any land mammal.

If you thought being pregnant for nine months was difficult, you should thank your lucky stars you aren’t an elephant. The African elephant has a gestation period of around 22 months, the longest of any land mammal. Asian elephants are also known for their lengthy gestation periods, between 18 and 22 months. But that’s just on land — things get a bit more extreme when you factor in creatures that live in the water. Take, for instance, the Chlamydoselachus anguineus, a shark found off the coasts of Chile and South Africa. This creature is believed to have a gestation period of up to 42 months, possibly due to its intensely cold habitat slowing down its metabolism. On the flip side, there are a few land mammals with gestation periods as short as 12 to 13 days, including the Virginia opossum and the water opossum.

Bennett Kleinman
Staff Writer

Bennett Kleinman is a New York City-based staff writer for Inbox Studio, and previously contributed to television programs such as "Late Show With David Letterman" and "Impractical Jokers." Bennett is also a devoted New York Yankees and New Jersey Devils fan, and thinks plain seltzer is the best drink ever invented.

Original photo by NASA/ Unsplash

It being a vacuum and all, space isn’t often thought of as having a scent of its own. And while no one has directly smelled outer space — exposure without a helmet would be fatal — many astronauts have reported that it smells like a mix of gunpowder and burnt steak. The odor is most noticeable after an astronaut returns to their spacecraft through the airlock and removes their helmet, at which point the lingering scent can be detected by both the astronaut who had been outside the ship and their crewmates who remained aboard.

The sun is one of the biggest stars.

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It’s actually quite average, with a radius of about 435,000 miles. The biggest known star, UY Scuti, has a radius of 738 million miles.

It’s been theorized that the source of space’s scent is dying stars, which release molecules called polycyclic aromatic hydrocarbons — a chemical compound also found in coal, oil, and food — as they near the end of their existence. There’s even a cologne named “Eau de Space” based on the smell, which was originally synthesized by biochemist Steve Pearce at NASA’s behest to better prepare astronauts for every aspect of the job. Based on his interviews with astronauts who had been to space, Pearce described the aroma as “hot metal, burnt meat, burnt cakes, spent gunpowder, and welding of metal.”

Numbers Don't Lie

Numbers Don't Lie

Dwarf planets in our solar system (Pluto, Ceres, Haumea, Makemake, Eris)
5
Craters on the moon officially recognized by the International Astronomical Union
9,137
Different types of olfactory receptors in the human nose
~400
Average surface temperature (in degrees Fahrenheit) of Neptune’s moon Triton
-391

Sunsets on Mars are the color ______.

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Sunsets on Mars are the color blue.

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A day on Venus is longer than a year.

There are many reasons why humans will never go to Venus — it’s so hot and uninhabitable that it’s been called Earth’s “evil twin” — but if we did, we’d experience something hard to imagine: a day that lasts longer than a year. It takes the planet 243 Earth days to fully rotate on its axis, but only 225 days to orbit the sun, meaning that a year on Venus is indeed shorter than a day there. This is believed to be due to the planet’s thick and stormy atmosphere, which slows down its rotation.  

Michael Nordine
Staff Writer

Michael Nordine is a writer and editor living in Denver. A native Angeleno, he has two cats and wishes he had more.

Original photo by Gatot Adri/ Shutterstock

It’s physically impossible to hum while pinching your nose. Go ahead, give it a try. See? To understand why humming, which we often associate with the mouth, would be affected by the nose, we have to look at the anatomy of our vocal folds. Vocal folds, aka vocal cords, are delicate bands of muscle located in the larynx, aka the voice box. When relaxed (i.e., when we’re quiet), our vocal folds resemble a wishbone. But when we speak, sing, yell, grunt, whisper — and, yes, hum — we send air up from the lungs and through the voice box. Simultaneously, those thin bands of muscle contract together, as if the open end of the wishbone has snapped shut. In reality, our vocal folds move in a wavelike pattern, vibrating against one another in varying frequencies that allow us to speak, sing, shout, and murmur. The faster our folds vibrate together, the higher the pitch; the slower, the lower.

We have “true” vocal cords and “false” vocal cords.

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“False” vocal cords, also known as the vestibular or ventricular folds, are thick folds of mucous membrane that sit above the “true” vocal folds to serve as backup protection against food or liquid entering the airway. Manipulating the “false” vocal cords can produce a deep, gravelly tone.

While we might think of humming as a sound that emanates from our mouth and lips, we actually produce this sound by sending air from the voice box to the nasal cavity and out through the nostrils. Thus, when we pinch our noses, there’s nowhere for the air to travel, and the vibration and corresponding sound stops. This also explains why pinching your nose mid-hum might make you feel like something’s caught in the back of your throat. (That’s the air trying to find a way out.) Another good way to test this theory is to hum when you’re congested. Depending on how blocked your nostrils are, you might not be able to hum at all, or you might even feel the mucus in your nose trying to move around as the air attempts to escape your nostrils — gross, but pretty interesting, too!

Numbers Don't Lie

Numbers Don't Lie

Frequency (in hertz) of the vocal folds of adult males
125
Year French anatomist Antoine Ferrein coined the term “vocal cords”
1741
Length (in millimeters) of vocal folds when we’re born
6-8
Length (in minutes) of the longest continuous vocal note
~2

In addition to the “humming” of their wings, Anna’s hummingbirds have distinct calls that last more than ______ seconds.

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In addition to the “humming” of their wings, Anna’s hummingbirds have distinct calls that last more than 10 seconds.

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There’s an Amazonian language that uses hums to communicate.

Pirahã is an Indigenous language spoken by fewer than 500 people. The Pirahã people live along a tributary of the Amazon River called the Maici River in northwest Brazil, and their language is largely regarded as one of the simplest tongues known to humankind. Its limited use of linguistic elements allows its speakers to communicate via humming, as well as yelling, singing, and whistling. You know when you’re trying to talk with a mouth full of food or while brushing your teeth and it comes out as a sort of rhythmic hum? The Pirahã language is a little like that — except its speakers actually understand what they’re saying to each other.

Melanie Davis-McAfee
Writer

M. Davis-McAfee is a freelance writer, musician, and devoted cat mom of three living in southwest Kentucky.