Ekkehard Peik thought it would take only a few months to create the basic ingredients of a radical new clock. That was back in 2001, when he and his colleague Christian Tamm proposed a device with ...

It's a simple enough idea; the Hubble Traveller Dot Clock has a pair of multicolor LEDs in the middle of it, stacked one on top of the other in mechanically driven rings. The light is focused ...