The science of Geodesy has undergone far-reaching changes in the last half century. The impact of new technology, from electromag netic distance measurements to the use of artificial satellites, has been great, and is still largely to be felt. These changes have forced the practitioners of the ancient art of Earth measurement to alter their way of thinking about the space that surrounds us, something fundamentally more difficult than absorbing a new technology. A key influence in this modem change in geodetic thinking has been the work of Antonio Marussi, in his scientific publications from 1947 onwards, through his students and collaborators at the Uni versity of Trieste, and in the series of symposia on three-dimensional Geodesy which he organised with his great friend and collaborator, Martin Hotine. His influence on the latter, stemming from their first meeting at the General Assembly of the International Association of Geodesy in Oslo in 1948, was remarkable in itself, leading as it did to the ultimate publication of Hotine's Mathematical Geodesy in 1969.

This volume contains selected papers by Torben Krarup, one of the most important geodesists of the 20th century. The collection includes the famous booklet "A Contribution to the Mathematical Foundation of Physical Geodesy" from 1969, the unpublished "Molodenskij letters" from 1973, the final version of "Integrated Geodesy" from 1978, "Foundation of a Theory of Elasticity for Geodetic Networks" from 1974, as well as trend-setting papers on the theory of adjustment.

The fourth edition of this textbook has been thoroughly revised in order to reflect the central role which geodesy has achieved in the past ten years. The Global Geodetic Observing System established by the IAG utilizes a variety of techniques to determine the geometric shape of the earth and its kinematics, the variations of earth rotation, and the earth’s gravity field. Space techniques play a fundamental role, with recent space missions also including gravity field recovery. Terrestrial techniques are important for regional and local applications, and for validating the results of the space missions. Global and regional reference systems are now well established and widely used. They also serve as a basis for geo-information systems. The analysis of the time variation of the geodetic products provides the link to other geosciences and contributes to proper modelling of geodynamic processes. The book follows the principal directions of geodesy, providing the theoretical background as well as the principles of measurement and evaluation methods. Selected examples of instruments illustrate the geodetic work. An extensive reference list supports further studies. The book is intended to serve as an introductory textbook for graduate students as well as a reference for scientists and engineers in the fields of geodesy, geophysics, surveying engineering and geomatics.

Apart from Hotine's work on Mathematical Geodesy, several previously unpublished reports are collected in this monograph, complemented by extensive comments on these contributions and a complete bibliography of Hotine by the editor.

The Glossary of Mapping Sciences, a joint publication of the American Congress on Surveying and Mapping (ACSM), American Society for Photogrammetry and Remote Sensing (ASPRS), and American Society of Civil Engineers (ASCE), contains approximately 10,000 terms that cover the broad professional areas of surveying, mapping and remote sensing. Based on over 150 sources, this glossary west through an extensive review process that included individual experts from the related subject fields and a variety of U.S. federal agencies such as the U.S.Geological Survey. This comprehensive review process helped to ensure the accuracy of the document. The Glossary of Mapping Sciences will find widespread use throughout the related professions and serve as a vehicle to standardize the terminology of the mapping sciences.

Geodesy (the measurement of the size and shape of the earth), fascinating since the time of Erathosenes, became a basic science for the space program. Irene Fischer was a leader in the construction of the World Geodetic System (has an Earth reference ellipsoid named in her honor) when it was still being done by surveyors, piecing together terrestrial, gravitational and astronomical data. By the 1970s, satellite geodesy and marine geodesy were just coming into their own. Using her career, Fischer revels in explaining how the science unfolded, and how misunderstandings occur across scientific fields, e.g., why the "standard ocean" and the geoid do not easily translate across the fields of oceanography and geodesy. Her account should appeal to those writing the history of women in science. Government science, too, is less well studied than academic science even though some fields, such as geodesy, were always government led. Fischer provides food for thought, as well, to those who claim to study the management of science in bureaucratic settings different from those of industry or academia. Peppered among these themes are Fischer's solutions to historical mysteries such as why Columbus' used a figure for the size of the earth's circumference that was so much smaller than Erastothenes' or Posidonius' (with the added benefit of making it easier to persuade his patrons).

"Physical Geodesy", published in 1967, has for many years been considered as the standard introduction to its field. The enormous progress since then has required a complete reworking. While basic material has been retained other parts are completely updated. However, there is a seamless welding of new ideas and methods (GPS, satellites, collocation). Highlights include: emphasis on global integration of geometry and gravity, a simplified approach to Molodensky's theory without integral equations, and a general combination of all geodetic data by least-squares collocation. In the second edition minor mistakes have been corrected.

Written by leading experts, this book provides a clear and comprehensive survey of the “status quo” of the interrelating process and cross-fertilization of structures and methods in mathematical geodesy. Starting with a foundation of functional analysis, potential theory, constructive approximation, special function theory, and inverse problems, readers are subsequently introduced to today’s least squares approximation, spherical harmonics reflected spline and wavelet concepts, boundary value problems, Runge-Walsh framework, geodetic observables, geoidal modeling, ill-posed problems and regularizations, inverse gravimetry, and satellite gravity gradiometry. All chapters are self-contained and can be studied individually, making the book an ideal resource for both graduate students and active researchers who want to acquaint themselves with the mathematical aspects of modern geodesy.

It was in September 1906 that the predecessor of the IAG, the 'Internationale Erdmessung', th organized the 15 General Assembly at the Hungarian Academy of Sciences in Budapest. It was 95 years later, in September 2001, that the IAG returned to this beautiful city to hold its Scientific Assembly, IAG 2001, in the historical premises of the Academy. The meeting took place from September 2-7, 2001 and continued the tradition of Scientific Assemblies, started in Tokyo (1982) and continued in Edinburgh (1989), Beijing (1993) and Rio de Janeiro (1997). Held every four years at the midpoint between General Assemblies of the IAG, they focus on giving an integrated view of geodesy to a broad spectrum of researchers and practitioners in geodesy and geophysics. The convenient location of the main building of the Hungarian Academy in downtown Budapest and the superb efforts of the Local Organizing Committee contributed in a major way to the excellent atmosphere of the meeting. As at previous meetings, the scientific part of the program was organized as a series of symposia which, as a whole, gave a broad overview of actual geodetic research activities. To emphasize an integrated view of geodesy, the symposia did not follow the pattern of the IAG Sections, but focussed on current research topics to which several IAG Sections could contribute. Each symposium had 5 sessions with presented papers and poster sessions on two consecutive days.

This volume gathers the proceedings of the IX Hotine-Marussi Symposium on Mathematical Geodesy, which was held from 18 to 22 June 2018 at the Faculty of Civil and Industrial Engineering, Sapienza University of Rome, Italy. Since 2006, the Hotine-Marussi Symposia series has been produced under the auspices of the Inter-Commission Committee on Theory (ICCT) within the International Association of Geodesy (IAG). The ICCT has organized the last four Hotine-Marussi Symposia, held in Wuhan (2006) and Rome (2009, 2013 and 2018). The overall goal of the ICCT and Hotine-Marussi Symposia has always been to advance geodetic theory, as reflected in the 25 peer-reviewed research articles presented here. The IX Hotine-Marussi Symposium was divided into 10 topical sessions covering all aspects of geodetic theory including reference frames, gravity field modelling, adjustment theory, atmosphere, time series analysis and advanced numerical methods. In total 118 participants attended the Symposium and delivered 82 oral and 37 poster presentations. During a special session at the Accademia Nazionale deiLincei, the oldest scientific academy in the world, six invited speakers discussed interactions of geodesy with oceanography, glaciology, atmospheric research, mathematics, Earth science and seismology.