From The New York Times, Olympics 2014: The Science of Snowmaking:
Machines make snow the same way nature does, by freezing water droplets. But they do it a few feet above the ground, rather than in the much colder conditions high in the atmosphere. Snowmaking machines employ a few thermodynamic tricks to help, but at times there is a limit to what physics can do…
…a droplet may not freeze entirely during the few seconds it takes to fall to the ground — what snowmakers call hang time.
“We’re basically making eggs,” Mr. Moulton said — icy shells around still-liquid centers.
Related snow videos: when nature handles it, How Is Snow Made?
…a very big meteor burned up over Chelyabinsk, a city in Russia just east of the Ural mountains, and about 1500 kilometers east of Moscow. The fireball was incredibly bright, rivaling the Sun! There was a pretty big sonic boom from the fireball, which set off car alarms and shattered windows.
Slate’s Bad Astronomy blog continues to update with videos and photos as more information is revealed (and corrected). In the incredibly clear video above, you can see the meteor as it was recorded on February 15, 2013 by a dashboard camera.
UPDATE: video link replaced.
From the archives: What is a meteor? And how do we study them?
Via Climate Adaptation.