Prof photographs the secret lives of snowflakes
Caltech snowflake specialist Kenneth Libbrecht shared his love for winter’s little ice crystals at Dal Wednesday.
January 16, 2014, 2:42 PM ADT
Last updated January 17, 2014, 2:04 AM ADT
Snowflakes don’t pose long for photos.
“You’ve got to get them while they’re fresh. They’re like fish,” says professor Kenneth Libbrecht of the California Institute of Technology.
The snowflake photographer and researcher of 15 years shared his technique at a public lecture at Dalhousie Wednesday. About 120 people heard his lecture at the Goldberg Computer Science Building on snowflakes as both science and art.
Libbrecht makes the picturesque a little easier to picture with his “travelling snowflake photo-microscope.” It has to travel because he lives in California.
Native to North Dakota he is no stranger to winter, calling the cold an “occupational hazard.”
He takes most of his flake photography in Alaska or Northern Ontario. He takes close-up photos of individual snowflakes, or ice crystals, gathered before they hit ground.
Libbrecht catches flakes on a piece of cardboard, and uses a paintbrush to pick up and place them on a slide.
Snowflakes are a delicate medium. But, “they’re falling out of the sky,” says Libbrecht. “You can break as many as you want.”
Though, you never get that same one again.
“No two crystals follow exactly the same path. So you don’t get two that are exactly alike.”
You have to photograph them quickly, before they melt. There is no using mashed potato in place of vanilla ice cream.
Snowflakes are made of clouds. Clouds are just tiny water droplets. At around -10 C or -12 C the cloud droplets start to freeze. These frozen droplets absorb the moisture around them, until they’re heavy enough to fall from the sky. It takes approx. 100,000 droplets to create a single snowflake.
Artificial snow, made for ski-hills, looks nothing like natural flakes, as these droplets freeze before hitting the air. Close up it looks like stuck together ice pellets.
Disney consulted Libbrecht’s expertise when producing the animated children’s movie Frozen, released before Christmas. He arrived at Walt Disney Studies to find his snowflake photos pasted on the wall.
“Mostly I told them: do not have any four-sided, five-sided, eights-sided, seven-sided [snowflakes]. They all have to be six,” says Libbrecht, laughing. Watching the film, he noticed that artistically the animators really stuck to the six-sided theme.
Disney’s production crew told him they “try to get the science right, and then put the fantasy on top.”
Libbrecht makes his own “designer snowflakes” in a controlled environment, simulating perfect conditions of -15 C with no wind.
There is a lack of research on crystal growth. Mineral crystals are found in nature and we have recipes for synthetic ones, but Libbrecht says these are largely from trial and error. He studies snowflakes to understand the fundamental physics of crystal composition.
Lots of laboratory research materials are dangerous or complicated to deal with. He says snowflakes are probably the cheapest and safest medium to research.
“If you spill it on the floor, it’s OK.”
Still, his work is more of a curiosity-driven science. “It’s hitting me in the face,” says Libbrecht. He wants to know why.
Dalhousie chemistry masters student Andrew Namespetra had never thought about the macroscopic properties of a snowflake, but just the snowflake as a whole.
“How the molecules pack really influences the crystal.”
He learned that a snowflake’s “shape is governed very much by the history of its lifecycle. Like humans – we’re shaped by what we’ve gone through.”
John Noel, also in chemistry at Dalhousie, says, “Most of the time I just hated snow because it means a lot of work. When you see it on a microscopic level you get an appreciation for the actual beauty that exists there.”
Noel studies materials, like ice, which store energy by changing their physical state.
Professor Kenneth Libbrecht has published seven books on snowflakes, including a coffee table book of photographs, a field-guide to snowflakes, and most recently a children’s book titled, The Secret Life of Snowflakes.