Science & Technology

The first key to thinking about 3-D printers is this: Do not think printer. Think magic box that creates any object you can imagine.

In the box, razor-thin layers of powdered material (acrylic, nylon, silver, whatever) pile one on top of the other, and then, voila — you've got a shoe, or a cup, or a ring, or an iPhone case.

It's miraculous to see. Press a button, make anything you want. But just how important is 3-D printing? Unlike earlier big-deal technologies (like, say, the tractor) 3-D printing won't really replace what came before.

Scientists have cooled potassium gas to one billionth of a degree below absolute zero. But in the quantum world, that's actually hotter than the Sun. It's hotter, even, than infinity degrees Kelvin. Vladan Vuletić, a quantum physicist at MIT, talks about this 'Bizarro World' temperature.

Catfish eating pigeons, water travelling uphill, a blue whale barrel roll — where can one see such things? The scientific journals! Flora Lichtman and Ira Flatow look back on the year's best moments in science cinema. What was your favorite science video of the year?

Cold-water fish, snow-dwelling bugs and some grasses have evolved natural antifreeze proteins to avoid turning to ice cubes. Peter Davies, a biologist at Queen's University in Ontario, discusses how these antifreeze substances work, and their applications for human problems--like keeping the ice out of ice cream.

In Full Planet, Empty Plates: The New Geopolitics of Food Scarcity, Lester Brown says the world's food supply is tightening, and the reasons are many. People in developing countries are eating more meat, a grain-intensive food; farmers are overpumping, causing water tables to fall; and crop yields have plateaued, despite technological advances.

In 2012 the Higgs boson was spotted at CERN, private company SpaceX began supply flights to the International Space Station, and the world bade farewell to the Galapagos tortoise Lonesome George. A panel of journalists discusses the year's top stories in science.

The comet ISON, discovered by two amateur astronomers last year, will zoom past the Earth next fall. But where did it come from? Astronomer Andrew Fraknoi says a passing star could have flung the comet our way from the Oort Cloud, a distant realm of ice chunks at the outer limits of the solar system.