Using Atomic Clocks and Quantum Gradiometers Onboard Satellites for Determining the Earth’s Gravity Field

Satellite missions like GRACE (now followed by GRACE-FO) and GOCE have remarkably advanced our knowledge on the global Earth’s gravity field, by measuring the first and second derivatives of the gravitational potential. However, a more precise gravity field model with better spatial and temporal resolution is still highly required by various geoscience disciplines such as oceanography, solid Earth physics, geodesy, etc. New technologies based on quantum optics emerged and quickly developed in the past years. They will enable novel observation concepts and deliver gravimetric observations with an unprecedented accuracy level in future. For the first time, optical clocks provide the particular opportunity to directly observe gravity potential differences through measuring the relativistic redshift between clocks connected by dedicated links (“relativistic geodesy”). Moreover, cold atom interferometry and optical gradiometers have extensively been studied. They will potentially provide gravity gradient measu...