Is it true that no two snowflakes are alike?

iStock/Marccophoto
iStock/Marccophoto

Up in the winter sky, water vapor in a cloud condenses into a droplet and freezes into a tiny bit of ice, with the water molecules bonding together as a hexagonal crystalline lattice with a six-fold symmetry. As water vapor condenses on its surfaces, the ice crystal grows into a hexagonal prism. As the crystal gets larger and larger, branches begin to form at the corners of the hexagon. When the crystal is heavy enough, it falls through the atmosphere toward the ground, where we call it a snowflake.

Many of those snowflakes have fallen onto the small town of Jericho, Vermont, the home of Wilson Alwyn Bentley. As a teenager, Bentley became interested in snowflakes, and he attempted to draw them while looking at them through a microscope his mother had given him. He found that he couldn't get the complex structures of the flakes down on paper before they melted, so he attached a camera to a microscope using an adjustable bellows mechanism and photographed his first snowflake on January 15, 1885.

Over the next few decades, Bentley continued to study snowflakes, taking 5,381 photographs of them and developing a system to categorize over 80 different flake types and shapes. In 1920, he became a Fellow of the American Meteorological Society and was awarded the Society's first research grant ($25). Bentley sometimes told people that he had never seen two snowflakes that looked alike and published several magazine articles arguing that no two flakes are identical. That idea stuck in the public imagination, which brings us to today's question: was he right?

Scientists have discovered that as an ice crystal gets blown around in the air while it grows, the environmental conditions it is exposed to and the timing of the exposure determine the shape of the snowflake. With different factors determining the snowflake's shape, and that shape changing as the growing snowflake moves through different conditions, you get a lot of variety in snowflake shape. Here's a handy little graph from a Caltech physics professor that shows which shapes occur in which conditions:

If two growing snowflakes are exposed to the same temperatures and humidity and water saturation levels at the exact same time (live out the exact same lives, if you will), they may look exactly alike at the macroscopic level. In fact, in 1988, the Nancy Knight was studying snowflakes as part of her work with the National Center for Atmospheric Research and found two identical snowflakes of the hollow column type in a Wisconsin snowstorm.

But Caltech physics professor and snowflake expert Kenneth Libbrecht (the man who made the above graph) points out that if you look at any two flakes "“ even seemingly identical ones "“ on the atomic level, you'll find numbers of water molecules and different layouts of those molecules (most water molecules contain an oxygen atom of 16O, but one molecule in every 500 has an 18O). One thing you won't find? Two snowflakes that are exactly alike.

If you've got a burning question that you'd like to see answered here, shoot me an email at flossymatt (at) gmail.com. Twitter users can also make nice with me and ask me questions there. Be sure to give me your name and location (and a link, if you want) so I can give you a little shout out.

Looking to Downsize? You Can Buy a 5-Room DIY Cabin on Amazon for Less Than $33,000

Five rooms of one's own.
Five rooms of one's own.
Allwood/Amazon

If you’ve already mastered DIY houses for birds and dogs, maybe it’s time you built one for yourself.

As Simplemost reports, there are a number of house kits that you can order on Amazon, and the Allwood Avalon Cabin Kit is one of the quaintest—and, at $32,990, most affordable—options. The 540-square-foot structure has enough space for a kitchen, a bathroom, a bedroom, and a sitting room—and there’s an additional 218-square-foot loft with the potential to be the coziest reading nook of all time.

You can opt for three larger rooms if you're willing to skip the kitchen and bathroom.Allwood/Amazon

The construction process might not be a great idea for someone who’s never picked up a hammer, but you don’t need an architectural degree to tackle it. Step-by-step instructions and all materials are included, so it’s a little like a high-level IKEA project. According to the Amazon listing, it takes two adults about a week to complete. Since the Nordic wood walls are reinforced with steel rods, the house can withstand winds up to 120 mph, and you can pay an extra $1000 to upgrade from double-glass windows and doors to triple-glass for added fortification.

Sadly, the cool ceiling lamp is not included.Allwood/Amazon

Though everything you need for the shell of the house comes in the kit, you will need to purchase whatever goes inside it: toilet, shower, sink, stove, insulation, and all other furnishings. You can also customize the blueprint to fit your own plans for the space; maybe, for example, you’re going to use the house as a small event venue, and you’d rather have two or three large, airy rooms and no kitchen or bedroom.

Intrigued? Find out more here.

[h/t Simplemost]

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

New Study Suggests That Raphael Died from Bloodletting and Pneumonia—Not Syphilis

Fever in the mornin', fever all through the night.
Fever in the mornin', fever all through the night.
Raphael, Uffizi Museum, Wikimedia Commons // Public Domain

On April 6, 1520, Italian painter Raffaello Sanzio da Urbino—better known as Raphael—died at just 37 years old from what was reported to be a fever. While the last 500 years have given rise to various theories about the details of this illness, the most popular explanation is that Raphael’s excessive philandering led to a fatal case of syphilis.

His free-loving lifestyle wasn’t exactly a secret, and painter Giorgio Vasari popularized the idea that this behavior was linked to his untimely demise in his 1550 book, The Lives of the Most Excellent Painters, Sculptors, and Architects:

"Meanwhile, pursuing his amours in secret, Raffaello continued to divert himself beyond measure with the pleasures of love; whence it happened that, having on one occasion indulged in more than his usual excess, he returned to his house in a violent fever. The physicians, therefore, believing that he had overheated himself, and receiving from him no confession of the excess of which he had been guilty, imprudently bled him, insomuch that he was weakened and felt himself sinking; for he was in need rather of restoratives."

But a new study published in the journal Internal and Emergency Medicine suggests that Raphael’s fever was a symptom of pneumonia—not venereal disease—and the doctors’ ill-conceived attempts to treat the infection with bloodletting contributed to his death. Sources from the time state that Raphael had a high, continuous fever that lasted anywhere from eight to 15 days, which a disease like syphilis wouldn’t typically cause.

“A recent sexually transmitted infection—such as gonorrhea and syphilis—could not explain the incubation period,” the study explains. “Similarly an acute manifestation of viral hepatitis could not be considered without jaundice and other signs of liver failure.”

Since there are no records of any typhus or plague outbreaks in Rome from that time period, and because Raphael didn’t appear to have any intestinal symptoms, University of Milan-Bicocca historian Michele Augusto Riva and other authors of the study landed on pneumonia as the most likely culprit. Though 16th-century physicians wouldn’t customarily treat respiratory diseases with bloodletting, it seems that Raphael didn’t give them much information to go on.

“[W]e are sure that bloodletting contributed to Raphael’s death," Augusto Riva told The Guardian. "Physicians of that period were used to practicing bloodletting for the treatment of different diseases, but it would not generally be used for diseases of the lungs. In the case of Raphael, he did not explain the origin of the disease or his symptoms and so the physician incorrectly used bloodletting.”

Draining a patient’s blood while he fights off a high fever seems like a painfully dimwitted idea by today’s standards, but it definitely wasn’t the worst remedy that Renaissance doctors had in their arsenal—read about 11 other wild ones here.

[h/t The Guardian]