Magnified Snowflake: ANRI

In today's links: declining mistletoe, burgeoning snowflakes, Santa, elves and more.

• This year, the tradition of a kiss under the mistletoe is safe. But the plant's habitat is in decline, and in the future, people may have to smooch under something else.
• The theory that no two snowflakes are alike is as much a part of winter as the one about Santa having eight reindeer. Here's a look at how snowflakes form the way they do.
• How does Santa get to all those homes? Relativity clouds. (Maybe.)
• If there's no sign of elves at the North Pole, that may be because they emigrated to Iceland. There, according to one researcher, there are 13 different types of elves, to say nothing of the trolls and fairies.
• As you ring in New Year's, have another drink. You're going to be getting an extra "leap second" in which to either party it up, or sleep it off, depending on how late you stay up.