Watt balance machine in operation, pan and reveal, at the National Institute of Standards and Technology, Gaithersburg, USA
{"Image ImageDescription": "Pan up to reveal the Watt Balance machine at the National Institute of Standards and Technology, Gaithersburg. It is an experimental electromechanical weight measuring instrument that measures the weight of a test object very precisely by the strength of an electric current and a voltage. The  team that work there are trying to redefine the kilogram.", "Image Copyright": "Big Wave Productions"}