In order to study this, they had to grow snowflakes in laboratory conditions. It was not an easy thing to figure out how to do. On his Snowcrystals page, physicist Kenneth G. Libbrecht show you how it's done.
There are many ways to grow snowflakes, but my favorite starts with something called a vapor diffusion chamber. This is essentially nothing more than an insulated box that is kept cold on the bottom (say -40C) and hot on the top (say +40C). A source of water is placed at the top, and water vapor diffuses down through the box, producing supersaturated air. The cold, supersatured air at the center of the chamber is ideal for growing ice crystals.
While working with this diffusion chamber, we rediscovered a wonderful technique for growing synthetic snow crystals that was first published in 1963 by meteorologist Basil Mason and collaborators . One starts by putting a wire into the diffusion chamber from below, so that small ice crystals begin growing on the wire's tip. Then apply a high voltage to the wire, say +2000 volts, and voila -- slender ice needles begin growing from the wire.
Brian Wansink is one of the most-cited nutrition researchers in the world; 30,000 US schools use his advice to design their lunch programs, drawing on studies he’s done that show that kids eat more carrots when they’re called “X-ray vision carrots” and that putting out fruit bowls improves eating habits, and that smaller plates reduce […]
A Chinese company developed a human sperm extraction machine for use in hospitals and other settings where human sperm may be required on the spot, but where conservative social norms or embarrassment make “while they wait” masturbation a difficult proposition. The Jiangsu Sanwe Medical Science and Technology Center says their device, which has been sold […]
“Gets stuff done,” is a good way to be described by anybody. Especially by coworkers or bosses. Because whether you’re in finance or a children’s librarian, stuff needs to get done. But how do you make sure stuff gets done? You definitely can’t do all the stuff yourself, unless your company/organization/government office consists entirely of you. And […]
Even the most expensive pair of hi-fi headphones can’t match the feeling of bass rumbling through your body at a live show. That’s why music aficionados designed The Basslet, an accessory that reproduces that sensation from your wrist. Does it make your whole body shake with deep subs? Not really, because that would be terrifying, but […]
They probably just sleep a lot. But still, you can remotely keep an eye on them when you’re at work and missing them deeply with this HD monitor from Kodak.If you have a new puppy that destroys everything in sight, or you just want to be a little more security-conscious, this WiFi camera is a […]