Harvard University scientists have created solar cells made from a single wire that's just 300 nanometers wide. The technology could be used to provide electricity to tiny sensors, or lead to cheaper solar power.

Each of the tiny wires is made up of layers of silicon that basically take over the job of semiconductors in conventional solar cells. Eventually, the nanowires could be packaged together into larger arrays, and might even lead to less-expensive rooftop solar panels. This research is just one aspect of a larger effort to make solar power more competitive with cheaper sources of energy, and according to scientists, it's an important step forward.—Gregory Mone

Via Technology Review

Devalued stocks, raging unemployment and weakened national pride plagued the 1930s, but PopSci escaped the Great Depression with a focus on fun inventions. A ride that “gives thrill seekers topsy-turvy sensations, comparable to those of looping the loop in a plane” graced our May 1934 cover, half a century after the roller coaster first appeared in American amusement parks. A giant steel arm swung this four-passenger car like a pendulum until momentum took over, hurling riders around a full loop.