Demand is soaring for the metal cobalt, an essential ingredient in batteries and abundant on the seabed.
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Doctors in the Netherlands say they are within 10 years of creating a 'second' womb for premature babies.
A rocket engine blew up in the Arctic, killing five nuclear experts and sparking a radiation scare.
Air travel accounts for 2%-3% of global greenhouse gas emissions. Are electric engines an answer?
Autonomous air taxis are still years away, but prototypes are creating a buzz at this year's Paris Air Show.
Designed by Scots engineers, the Phoenix is a new type of plane which can travel long distances and stay aloft for long periods.
NBC News obtained a photo showing results of a test on a steel wall prototype.
The Spanish foreign minister says he disagreed with the idea, put to him during a visit to the US.
Cigarette butts have long been the single most collected item on the world's beaches, with a total of more than 60 million collected over 32 years.
Kalashnikov's electric CV-1 is described as a "cutting-edge supercar" styled on a 1970s hatchback.