 I have with me Dr. Yorg Han, who's a system engineering manager in the European Space Agency's program for satellite navigation Galileo. Galileo is of course named after the famous Italian astronomer and mathematician of the 17th century. Dr. Yorg Han, we are here today looking at existing and new navigation systems that are literally changing the way transportation systems work and the way we find our way around the world. Now, what exactly is the navigation system that you're working on? Thank you first of all for being here in this BIPM ITU workshop. We appreciate very much with Galileo. Our position is of interest to the community and we are happy here to contribute to establishing a good position for that decision on leap seconds. Secondly, we are building the European component to the so-called GNSS, which is the Global Navigation Satellite System, which is basically a system contributed by many different systems like GPS, GLONASS, GPS of the US and GLONASS of the Russian Federation, Baidu of the Chinese. And Galileo is basically the European contribution to that. It is an autonomous system built up under full civilian control. This system will be fully interoperable with the US system GPS, which many of us know today, and the GLONASS system of the Russian Federation. Our system will provide from the outset dual-frequency signals to the public and this allows from the beginning for meter-level accuracy, which is much better than what we have today. In addition, this system, which will consist of 30 satellites in the end, by the way, 27 operational satellites and three active spare satellites, this system will provide global services for all communities interested. This system is not just the space segment, it contains also a ground segment, which is distributed worldwide with sensor stations gathering data and collected and sent to our tool control centers we have in Europe, in Italy, in Fuccino, and in Oberpfaffenhofen in Germany. To send these data, we use a redundant network, communication network, and in order then to communicate with our satellites, we use uplink stations to control the satellites and to provide mission navigation data. At ITU, we've been discussing the future of the international time scale. Now, does the Galileo system work on a different time scale from UTC or is it based on UTC? Okay, the Galileo system works with an internal time scale. This is quite similar to what GPS does. GPS time is quite known to many people in the science community and engineers. So our time scale is called Galileo system time, GST. So this is an internal time scale, it's a continuous time scale, which is steered to UTC, modulo one second. So that means it does not have leap seconds as such, it's really a continuous time scale, but the information on leap seconds is made available to the users. Universal time is coordinated with the addition of the leap second. Now, there's a proposal to eliminate this leap second. What is your opinion on that? Okay, we have carefully, of course, investigated this situation. We are, as Galileo, we are also following the discussions since many years. So myself, even I was involved some years ago in a workshop in London, for instance. The situation indeed is our internal operations run with system time of Galileo, GST. So everything internally is time-tact to GST. The operator uses GST, but I must say also for operations scheduling, the operator for convenience is using also UTC. You see this a lot in the displays. So scheduling, planning aspects are done in UTC. Since our system cannot run in full isolation of the world, we need also external connections to communities, as I said. So we have this time service provider. The files we get, they are tagged in UTC. We have also a link to the Geodesy community, international earth rotation service, Geodesy, and they also time-tact in UTC. As such, we are impacted indeed if there's a leap second coming. And this creates quite an inconvenience. I have to say... What happens when you put in the leap second? I have to say, the system is designed to cope with leap seconds. But what you have to do, you have to change configurations on the elements. You have to check for the proper implementation. You have even to test it. And in the end, it's always an operational hazard. So if you look at the operators, they don't like that today. And our position, coming then back to the original question, indeed to facilitate the operations and to increase the robustness of our Galileo system, we would be in favor, in principle, to abandon the leap seconds. We have also to say, of course, there is a famous parameter under discussion, the DUT1 parameter. And this parameter would grow eventually above the one-second range today. And this would cause some, let's say, changes we have to do on our interfaces to the external world, for instance, to cope with this kind of offset. And so to ensure that the operations will continue smoothly. Having said so, we have to change interfaces in our system. We are also considering, once such a decision would be taken, to consider the provision of this DUT1 parameter for Galileo. So we look forward to having Galileo working fully. And we look forward to using it as users in a normal day-to-day functioning. Thank you very much, Dr. Han, for coming with us to ITU. Thank you very much. Thank you.