Six million snowflakes fell from the sky this winter. These are billions of billions of them, which are now mostly melted away as spring approaches.
Few people looked at them one by one.
Kenneth G. Libbrecht, a professor of physics at the California Institute of Technology, spent a quarter of a century trying to understand how such a simple substance – water – can freeze in a multitude of forms.
“How do snowflakes form?” Dr. Libbrecht said during an online talk on Feb. 23 presented by the Bruce Museum in Greenwich, Conn. “And what do these structures look like – and, as I like to say, literally from the air?”
One of the people described by Dr. Libbrecht’s research and photography on snowflakes fascinated him was Nathan P. Myhrvold, a former chief technology officer at Microsoft, who has since followed projects in countless scientific disciplines, including paleontology, cuisine and astronomy.
Dr. Myhrvold, an avid photographer, met dr. Libbrecht first met more than ten years ago and in the spring of 2018 he decides that he wants to take the intricate frozen crystals himself. He remembers thinking, ‘Oh, we’ll just throw something together, and we’ll be ready for winter.’
But as with many of his projects, things were not as simple as dr. Myhrvold did not plan.
“It seems to be extremely complicated than I thought,” said dr. Myhrvold said. “So it took 18 months to build the damn thing.”
The ‘damn thing’ was the camera system for photographing snowflakes. He wanted to use the best digital sensors, one that captured a million pixels. “The real snowflake is very, very fragile,” he said. “It’s very complicated. So you want high resolution. ‘
But the type of sensor is much larger in area than the images usually produced by the lenses of microscopes, due to decisions made by microscope manufacturers about a century ago.
That means he had to find a way to stretch the image of the microscope to fill the sensor.
In his tampering, “I devised a personal optical path that would make it work,” he said.
Then there is the housing for the optics. It is usually of metal, but metal expands when it is hot and shrinks when it is cold. By moving the device from the warm indoor to an ice-cold balcony where he would collect the snowflakes, it would screw up the entire microscope, Dr. Myhrvold said and made it impossible to keep everything in focus.
Instead of metal, he used carbon fiber, which does not expand or shrink significantly.
Dr. Myhrvold also found a special LED manufactured by a company in Japan for industrial use, which would emit 1 / 1,000th of a light source, as long as it was an ordinary flash of the camera. This reduces the heat radiated by the flash, which can melt the snowflake a bit.
To look at something under a microscope, a sample is usually placed on a glass plate. But glass retains heat. It also melts the snowflakes. Therefore, he switched from glass to sapphire, a material that cools more easily.
By February 2020, he was ready. But where do you find the most beautiful snowflakes to photograph? At first he thought he could just go to a ski resort – maybe Aspen or Vail in Colorado or Whistler in British Columbia.
But these places were not cold enough.
“Powder snow that a skier would like to ski through is in fact a lot of powder,” said dr. Myhrvold said. “There’s not much beauty in things.”
Indeed, the snowflakes that mostly fall on most people are rarely what people consider to be snowflakes.
Water is a simple molecule made up of two hydrogen atoms and one oxygen. When the temperature drops below 32 degrees Fahrenheit, the molecules begin to hold on to each other – that is, they freeze.
A snowflake is born in a cloud when a drop of water freezes in a small ice crystal. The shape of the water molecules causes them to stack together in a hexagonal pattern. Therefore, the archetypal snowflake has six arms.
Then the crystal grows, absorbs water vapor from the air and other droplets in the environment evaporate to replenish the vapor. “It takes maybe 100,000 water droplets that evaporate to make one snow crystal,” said Dr. Libbrecht said.
But how the crystal grows depends on the temperature and the humidity. In the 1930s, a Japanese physicist, Ukichiro Nakaya, was the first to grow artificial snowflakes in his laboratory, and by changing the conditions, he was able to catalog the types of mold under most conditions.
If the temperature is just below freezing, the snowflakes are generally simple hexagonal plates. At about 20 degrees Fahrenheit, the common shape is hexagonal columns. The archetypal beautiful snowflakes usually form between 15 and -5 degrees Fahrenheit.
At these temperatures, the tips of the hexagon grow into branches. The branches then spawn other branches and smaller hexagonal plates. Slight variations in temperature and humidity affect the growth pattern, and conditions constantly change as the snowflake falls to the ground.
“Because it has this intricate path through the clouds, it gives it an intricate shape,” said Dr. Libbrecht said. “They all follow different paths and therefore each one looks a little different, depending on the road.”
So, to find the beautiful snowflakes, dr. Myhrvold north, much further north. He and a few assistants hauled about a thousand pounds of equipment to Fairbanks, Alaska; Yellowknife, the largest community in the Canadian Northwest Territories; and Timmins, Ontario, about 150 miles north of Lake Huron.
A month later, the coronavirus pandemic brought the attempt to a halt. But dr. Myhrvold was able to take the highest resolution photos of snowflakes ever.
This claim has irritated others in the snowflake world, including Don Komarechka, a Canadian photographer who follows a decidedly lower-tech approach. He uses a digital camera purchased in the store with a strong macro lens. He does not even use a tripod – he just holds the camera while the snowflakes sit on a black hand that his grandmother gave him.
“Incredibly simplistic,” he said. Komarechka said. “It’s so accessible to anyone with any camera.”
He said of Dr Myhrvold’s bespoke system: “I think it’s a bit of a design.”
Mr. Komarechka also takes a different approach to illumination using the light reflected by a snowflake, while dr. Myhrvold’s images capture the light that passes through. “You see surface texture and sometimes beautiful rainbow colors in the middle of a snowflake,” he said. Komarechka said.
The rainbow effect is the same as what you see in a soap film, but the colors ‘appear much firmer than you would see in a soap film or anything else,’ he said. “It’s almost psychedelic colors that look almost like a tie-dyed T-shirt.”
To meet the demands of dr. To counter Myhrvold, Mr. Komarechka took an image that he said was an even higher resolution. Dr Myhrvold responds with a long refutation and explains why his images were more detailed.
In practical terms, dr. Myhrvold’s images sharper when printed on large printing paper. It is for sale in sizes up to 2 meters by 1.5 meters.
“In the very narrow sense, yes, that’s what Nathan claims, and he’s not wrong,” Dr Komarechka said.