Raumfahrtgravimetrie

Raumfahrtgravimetrie refers to the measurement of Earth's gravity field from space. This is primarily achieved using satellites equipped with specialized instruments that can detect tiny variations in gravitational acceleration. By precisely tracking the orbits of these satellites and observing how their speed changes due to gravitational pull, scientists can create detailed maps of the geoid, which is the equipotential surface of Earth's gravity field that best approximates mean sea level.

The principle behind Raumfahrtgravimetrie involves measuring the distance between two satellites in a constellation or the acceleration of a single satellite. Instruments like gradiometers measure the difference in gravitational force across a certain distance, providing high-resolution information about local gravity anomalies. Alternatively, satellite-to-satellite tracking, where a leading satellite measures the acceleration experienced by a trailing satellite, can also reveal gravity field variations.

These gravity maps are crucial for a wide range of scientific and practical applications. They aid in understanding the Earth's internal structure, including the dynamics of the mantle and core. Furthermore, Raumfahrtgravimetrie plays a vital role in oceanography, helping to determine ocean currents and sea surface height anomalies, which are influenced by the underlying gravity field. It is also essential for precise navigation, geodetic surveying, and monitoring changes in groundwater storage and ice mass. Missions like GRACE (Gravity Recovery and Climate Experiment) and GOCE (Gravity Field and Steady-State Ocean Circulation Explorer) have significantly advanced our understanding of Earth's gravity field through Raumfahrtgravimetrie.