ESA Portal - PHARAO atomic clock agreement signed by ESA and CNES

PHARAO atomic clock agreement signed by ESA and CNES

15 December 2009



ESA Portal - PHARAO atomic clock agreement signed by ESA and CNES

PHARAO atomic clock agreement signed by ESA and CNES

15 December 2009
ESA PR 31-2009 Today at the Paris headquarters of the French space agency (CNES), Simonetta Di Pippo, ESA Director of Human Spaceflight, and Thierry Duquesne, CNES Director for Strategy, Programmes and International Relations, signed an agreement that paves the way for the launch of a high-accuracy atomic clock to be attached to the outside of the European Columbus laboratory onboard the International Space Station (ISS).

The PHARAO (Projet d’Horloge Atomique par Refroidissement d’Atomes en Orbite) atomic clock, which will be combined with another atomic clock, the Space Hydrogen Maser (SHM), to form ESA’s Atomic Clock Ensemble in Space (ACES), will have an accuracy of 1x10^-16, corresponding to a time error of about one second over 300 million years.

This new generation of atomic clocks in space will be instrumental in enabling accurate testing of Einstein’s theory of general relativity. In addition, it will contribute to the accuracy and long-term stability of global timescales, e.g. International Atomic Time (TAI) and Coordinated Universal Time (UTC), and also help in the development of applications in the field of geodesy, and support applications involving remote sensing via the GNSS network.