Geoid (IMAGE) Physikalisch-Technische Bundesanstalt (PTB) Caption It resembles a baggy football: this is the Earth when it is represented as a geoid, i.e., when the actual distribution of the gravitational force is shown. Here, the height of the "bumps," which are related to the gravitational field of the Earth, has been determined by the Goce satellite. Although the data are precise as far as the respective height of the "humps" is concerned, the lateral resolution amounts to a few kilometers. In future, frequency comparisons between optical atomic clocks can be used if one wants to know the height of the smaller structures and places on Earth. Now it will be possible to transport the frequency over a distance of approximately 2,000 km with a resolution which corresponds to a height difference of only 4 mm if the remote clocks support such accuracy. Credit ESA Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.