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.
I learned that there are two forms of mimicry in nature — honest mimicry (e.g., bees and wasps look similar and advertise that they can sting) and dishonest mimicry (e.g., some flies look like bees and wasps to trick predators into thinking they can sting). Inés Dawson, a graduate and PhD student at the University […]
In 1960, parapsychologist Anthony Donald Cornell donned a bed sheet and attempted to scare an audience watching an X-rated film in a movie theater. Why? Cornell, a believer in ghosts himself, wanted to understand how people reacted during “apparitional experiences.” Today at the BBC, University of Oxford experimental psychologist Matthew Tompkins explores Cornell’s strange experiments […]
With so many costumes adorning this election season, you might think the Halloween get-ups are overkill. Think again, because David Ng and B.R. Cohen are here to present the official universal survey about your candy favorites for the 2016 hierarchical delineation of candy virtue.
With Xamarin, coders can develop native apps for both iOS and Android without learning two different programming languages. Obviously, hiring one programmer rather than two is beneficial for companies and makes Xamarin experts highly in demand.You can easily learn Xamarin online with this Xamarin Cross-Platform Development Bundle. It will teach you to use Xamarin and code […]
TV antennas are making a comeback, and the Ghost Indoor HDTV antenna is a great example of why. Unlike the old bunny ear-style antennas, this compact antenna is barely noticeable and picks up channels easily. Plus with the addition of streaming services like Netflix, we find ourselves with plenty to watch without a pricey monthly cable bill. The Ghost […]
I’ve never really felt the need to purchase a smartwatch because a lot of them aren’t very functional, but at just shy of $30, the Martian Notifier Smartwatch was worth checking out. For that low of a price, it actually does feature an impressive amount of functionality, and comes in handy when you don’t want to be carrying around your […]