The science of Christmas

It’s beginning to look a lot like … science, and now, everywhere you go, you can dazzle people with the latest research on snowflakes, Santa doing the time warp again and the lunar accuracy of gift wrap. Read on …

Santa’s amazing journey

How does Santa make it to millions – billions? – of houses every Christmas?

Well, according to Larry Silverberg, a professor of mechanical and aerospace engineering at North Carolina State University, Santa relies on electromagnetic waves, the space-time continuum, nanotechnology, genetic engineering and computer science.

While Silverberg’s contention that Santa fabricates presents on location using a nano-toymaker may seem a little far-fetched – generating gifts in each good little boy’s and girl’s house atom by atom out of snow and soot – who can really argue with the idea of relativity clouds for travel?

“Santa recognizes that time can be stretched like a rubber band,” Silverberg said in a news release. “Relativity clouds are controllable domains – rips in time – that allow him months to deliver presents while only a few minutes pass on Earth.”

Silverberg also suggests that Santa’s reindeer are genetically bred with enhanced night vision, good balance and the ability to fly, and that the fat man listens to children’s thoughts via an antenna using cellphone and EKG technology.

But Silverberg notes that old-fashioned letters to Santa work just as well.

“Santa,” he says, “is, in many ways, a traditionalist.”

Is this flaky or not?

Snowflakes taste good, sure, but they’re really at their best as eye candy.

Caltech physicist Kenneth Libbrecht, whose name is synonymous with the science of snowflake formation, has been trying to find out why different shapes form at different temperatures.

On his website, Libbrecht points out that 28 degrees Fahrenheit will get you “thin plates and stars” and 23 degrees produces “columns and slender needles.”

Just to complicate things, 5 degrees means a return to plates and stars, and minus 22 degrees results in a combination of plates and columns.

Humidity also plays a role – the most extreme shapes form when there’s more water in the air.

But.

But, but, but.

Libbrecht wanted to know why relatively minor changes in temperature (Minor? From 28 above to 22 below? Really?) cause big changes in snowflake shapes.

“What I found in my experiments,” Libbrecht said in a news release, “is a growth instability, or sharpening effect.”

The author of the release interprets the statement thusly: “Basically, the corners stick out a bit farther toward the moist air, so they grow faster.”

The release says that Libbrecht cannot yet explain why different temperatures make sharp points on different bits of the snow crystal, but it’s a start.

“This,” Libbrecht says, “is a real advance in snowflake science.”

Maybe it’s just a phase

When Santa flies through the moonlight, is it coming from a waxing crescent, a waning crescent, a half moon or a full moon?

Peter Barthel of the Kapteyn Astronomical Institute in the Netherlands decided to find out. In what he calls a jolly but “definitely incomplete” study of books, gift wrap, greeting cards and other seasonal items in the Netherlands and the United States, Barthel determined that many illustrations of the moon are scientifically inaccurate.

Barthel bases his conclusions on the fact that a waxing crescent moon (lit on the right side if viewed from the Northern Hemisphere) disappears by midnight. A waning crescent moon (lit on the left side) doesn’t appear until around 3 a.m.

As an example, he found a UNICEF Christmas card from 2010 showing children decorating an outdoor Christmas tree. “Judging from the moon phase, the scene takes place at 4 a.m. or 5 a.m. in the morning, which is not impossible but unlikely,” Barthel writes in the December issue of the journal Communicating Astronomy with the Public.

Seventy percent of the 30 American books he examined show a full moon while Santa delivers gifts, which is the easy way out (it’s just a circle, right?) but ultimately correct, while 40 percent of the 25 books examined in the Netherlands showed an incorrect last-quarter crescent moon.

On the gift wrap-card side of the research, the States again went for the full moon, while 65 percent of gift wrap analyzed in the Netherlands showed an incorrect crescent moon phase, he wrote.

“It must be concluded that the Americans are occasionally wrong, but not as frequently as the Dutch,” he wrote, and followed that up with an appropriate question: “Who cares?”

Santa’s night flight provides an easy opportunity for moon phase education, Barthel wrote, and that leads to more appreciation of its beauty.

“‘You better watch out’ is often heard in the December month,” he wrote. “It should also be taken literally.”

Diane Tennant, (757) 446-2478, diane.tennant@pilotonline.com