Atomic Clocks in Space
Prof Michael Tobar
University of Western Australia
The Atomic Clocks Ensemble in Space mission is a cornerstone European Space Agency mission in fundamental physics and technology based upon the operation of precise clocks in the microgravity environment of the International Space Station. The time scale will be delivered to Earth through a high-performance microwave link, which will be used to make space-to-ground and ground-to-ground comparisons, thus permitting synchronization of world clocks with unprecedented sensitivity, allowing
the following experiments: (i) a gravitational red-shift experiment a factor of 35 better than previous best, (ii) tests on the invariance of fundamental physical constants at the level of 10-17/year, (iii) tests on the anisotropy of the speed of light (odd parity test) better than 10-10, (iv) demonstration of relativistic geodesy from space allowing measurement of height differences at the cm level on a near global scale, (v) the availability of better clocks and high performance time and frequency transfer links for the validation of the Global Navigation Satellite Systems (GNSSs), (vi) as well as other research that utilizes GNSS hardware such as radio occultation and reflectometry.
Professor Tobar is an ARC Laureate Fellow with the School of Physics, University of Western Australia. His research interests encompass the broad discipline of frequency and quantum metrology, precision measurement and precision tests of the fundamental of physics. He is also the focal point of Australian participation in space experiments involving precision clocks and oscillators, including the only non-European Scientific Coordinator of the Atomic Clock Ensemble in Space mission. Tobar was the recipient of the 2010 WA scientist of the year award, presented by the Western Australian Department of Commerce, 2009 Barry Inglis medal presented by the National Measurement Institute, the 2006 Boas medal presented by the Australian Institute of Physics. He has published more than 175 refereed journal papers across his areas of research.