Credit Kevin Ma, Pakpong Chirarattananon / AAAS/Science
These robotic flies, which were built in a Harvard lab, can flap their wings independently of each other and fly around while tethered to a power and control wire.
Credit University of Illinois and Beckman Institute
An insect's eye lets it see really well because each of its light-sensitive cells has a dedicated lens. This miniature camera, which mimics an insect eye, is made from an array of microlenses arranged on a stretchable sheet that can be inflated like a balloon to a hemispherical shape.
A smartphone can tell you where to get a cup of coffee, but it can't go get the coffee for you. Engineers would like to build little machines that can do stuff. They would be useful for a lot more than coffee, if we could figure out how to make them work.
But the rules of mechanics change at small scales. Friction becomes dominant; turbulence can upend a small airplane.
Colorado Governor John Hickenlooper, center, exits the Fort Lyon Correctional Facility in Las Animas, Colo., on Wednesday after touring the facility. Hickenlooper has proposed closing the facility due to budget concerns.
The government of Kazakhstan says it's cooperating with U.S. officials in the investigation of the Boston Marathon bombings, a day after two men from the Central Asian country were charged in connection with the blasts that killed three people and wounded more than 250.
For years, many marine biologists have argued that the floating, open-ocean net pens that produce billions of pounds of salmon per year also generate pollution, disease and parasites.
In some places in western Canada, the open-ocean salmon farming industry has been blamed for the collapse of wild salmon populations in the early 2000s — though other research has challenged that claim.