Selected Papers from TimeNav 2007

As long as people have been navigating, they have needed to know how to measure time. Technology has changed the required level of precision, and the details of the application, but to-date some knowledge of time has always been required. In the earliest days, people would decide when to turn left or right by how many hours they had been walking or sailing. In the eighteenth century, contests were held and prizes awarded to those who could construct clocks accurate to the minute over monthly periods, so as to measure the longitude for navigational needs. And now, in the twenty-first century, we find navigation is dominated by radio-based global navigation satellite systems (GNSSs), which cannot function without knowledge of the time at the nanosecond level. In April 2007, three important international meetings devoted to time, frequency, and navigation were held together in Geneva under a common umbrella aiming to promote the interchange of these communities. The meetings were