杏吧原创

Success for F-35 ejection seat test

Despite budget overruns and software failures, Lockheed Martin鈥檚 F-35 Lightning stealth fighter should go on active duty later this decade. And if anything should go wrong with one of these multimillion-dollar planes, the pilot should be able to escape safely. Last week, a full-scale mock-up of the cockpit was strapped to a rocket sled and shot down a track in Chalgrove, UK, at over 950 kilometres per hour. When an 鈥渆ject鈥� handle was pulled, small explosives broke away the canopy, the ejection system fired, and the parachute opened 鈥� all inside 3 seconds.

A barcode scanner for zebras鈥� stripes

Zebras鈥� black-and-white stripes have been turned into biological barcodes, thanks to a computer program developed by Mayank Lahiri of the University of Illinois, Chicago, and colleagues. The StripeSpotter allows researchers to identify individual animals from a single photo. Simply snap a picture of your favourite zebra, use the program to outline the animal鈥檚 torso with a rectangle, and the computer converts the image into a pattern of black and white pixels unique to each beast. This pattern can then be used to identify photos of the same animal.

Quantum holograms are colour-safe

Holograms shift in colour depending on the angle you look at them. But now Satoshi Kawata at the RIKEN Institute in Japan and colleagues have taken advantage of a quantum effect to produce holograms that stay the same colour no matter your perspective. They used thin metal films, which contain free electrons that oscillate on the surface and interact with incoming photons. By etching holograms on 55-nanometre-thick films with red, green and blue lasers, the team encouraged the wave of surface electrons to resonate with the three different wavelengths in such a way that they cancelled out the colour-changing effect of viewing angle (Science, ).