In orbit demonstration of a H-maser clock system

The ESA/NASA technology demonstration flight of a pair of hydrogen masers on the EURECA 3 mission is planned for 1998. The ESA part of the experiment will have a maser built by Neuchatel Observatory and a microwave time and frequency transfer system derived from the existing Precise Range and Range Rate Equipment (PRARE) system. The NASA part of the experiment will have a maser built by the Smithsonian Astrophysical Observatory and a laser time transfer system. The technology demonstration experiment is described with its expected outcomes and applications.