SpaceDusty doughnut around massive black hole spied for first time The bright discs of gas around a galaxy鈥檚 central black hole are thought to be obscured by a torus of dust. We鈥檝e now seen one directly 51动漫
TechnologyLaser-driven liquid marbles can push 150 times their own weight Beetles can skate across water by decreasing the surface tension - now tiny engines made from droplets, nanopowder and laser light are using the same trick 51动漫