An astonishingly precise high-speed camera has revealed what snow looks like as it falls.
A novel three-camera system developed at the University of Utah has spent two years trying to catch the elusive sight as snow flakes collect together and fall in mid-air.
The pictures don't look like the perfect flat snowflakes seen in photos, but rather strange, irregular and 3D shapes that form and merge as they drift to the ground.
The camera, funded by the US Army and Nasa, will help understandings of how snow interacts with radar, improving snow forecasting.
The 'Multi-Angle Snowflake Camera' can take 3D images, with two industrial-grade 1.2 megapixel sensors and one 5-megapixel camera, plus two sets of motion sensors to measure the speed of falling snow.
Snowflakes In Slow-Motion
"Until our device, there was no good instrument for automatically photographing the shapes and sizes of snowflakes in free-fall," said Tim Garrett, an associate professor of atmospheric sciences at Utah.
"We are photographing these snowflakes completely untouched by any device, as they exist naturally in the air."
Garrett said that the traditional image of snowflakes is partly due to photographers picking those few which lie flat on a microscopic slide.
"These perfectly symmetric, six-sided snowflakes, while beautiful, are exceedingly rare – perhaps one-in-a-thousand at the most," said Garrett, according to Phys.org.
"Snow is almost never a single, simple crystal. Rather, a snowflake might experience 'riming,' where perhaps millions of water droplets collide with a snowflake and freeze on its surface."