Caltech physicist Ken Libbrecht deals with gravity-wave detectors, tunable diode lasers and nanoscale crystal growth, but his biggest claim to fame is snowflakes. How many other physicists can brag that their work has been printed on postage stamps? Not that Libbrecht is the kind of person to brag, but if he was, he'd have one more thing to brag about: Sweden's Lennart Nilsson Award, a 100,000-kronor ($15,000) prize given annually to honor scientific and medical photography.

"Kenneth Libbrecht's images open our eyes to the regularity and beauty of nature," the board said in its citation. "With his photographs of snowflakes, he turns mathematics, physics and chemistry into images of great beauty."

Over the years, Libbrecht has perfected his formula for capturing the microscopic crystalline structure of frozen water in photographs -- to the point that he's authored several books on the subject. His recipe for preserving snowflakes on a microscope slide, involving a "1 percent solution of polyvinyl acetal resin," even made it into the script for an episode of "The Big Bang Theory" on prime-time television.

Probably one of the most often asked questions he faces is a classic: "Is it true that no two snowflakes are alike?" He provides the most reasonable answer: No two snowflakes are exactly alike, but they can look alike. (Other researchers have taken a similar stance.)

Libbrecht is due to pick up his award next week at Berwald Hall in Stockholm, with Swedish photographer Lennart Nilsson himself in attendance. The Swedish Postal Service will also be issuing a set of Libbrecht snowflake stamps next month. Some parts of Sweden can be pretty chilly this time of year, but it's nice to know the Swedes are giving the king of snowflakes a warm reception.

More about snowflakes and winter:

• The science behind snowflakes, in verse
• Visit a winter wonderland of science
• 10 more wonders for wintertime
• Snowflakes on Christmas cards drawn wrong