Ohio State nav bar


What Is Geodesy?

Geodesy is the science of determining the size and shape of the Earth (including its temporal variation) using measurements primarily (today) of distance, time, and gravity. Being one of the oldest sciences, with a history of more than two thousand years, the traditional measurements were mostly associated with land surveying (distance and direction measurements of landmarks and celestial objects) and gravity observations (to determine the geoid, as reference surface for heights, and the plumb direction). The age of satellites, radio science, and computer technology have completely transformed these methods and enabled geodesy to branch into many of the Earth sciences where the exquisite measurement precision has enabled the determination of ocean level variations, crustal deformation, tectonic plate motions, ice sheet heights, Earth rotation variation, and other geodynamical phenomena with unprecedented detail and accuracy. Contemporary geodesy utilizes the latest in mathematical modeling, physics research, astrometry, computer science, and statistical analysis to aid in the understanding of ocean currents, sea level rise, the world's hydrological cycles, atmospheric conditions, global climate change, post-glacial rebound, and other crustal deformation, particuarly as it relates to natural hazards, such as earthquakes, volcanoes, and flooding. In these Earth science applications, accurate coordinate reference frames, high-resolution global gravity models, and precise time keeping are of paramount and fundamental importance. Geodesy, of course, continues the tradition of forming the backbone for all national and international datums and reference systems needed to establish three-dimensional positional control of regional and global networks of terrestrial points. Several geodetic principles and techniques also have found application in studies of the Moon and other planets.


Stud. Hist. Phil. Mod. Phys., 31(3):371-404


A Brief History of Geodesy at OSU

1947: The Mapping and Charting Research Laboratory first offers degrees.

1950: The Institute of Geodesy, Photogrammetry, and Cartography is established (G. Harding, Director; W.A. Heiskanen, Scientific Director).

1953: First M.S. degree is awarded (to W.M. Kaula).

1955: First Ph.D. degree is awarded (to C.E. Ewing).

1961: The Institute becomes the Department of Geodetic Science in the College of Mathematical and Physical Sciences.

1964: Prof. Urho Uotila begins 20-year chairmanship of the Department.

1975: B.S. in Surveying is added.

1981: The department name changes to Geodetic Science and Surveying.

1984: Prof. Ivan Mueller becomes chair of the Department.

1986: 35 years of Geodetic Science at OSU. The Center for Mapping is established, largely with efforts by the Department; Prof. John Bossler becomes its director.

1992: Prof. Clyde Goad becomes chair of the Department.

1995: The Department is tranferred to the College of Engineering under a university-wide re-structuring exercise.

1996: The Department merges with Civil Engineering, which becomes Department of Civil and Environmental Engineering and Geodetic Science.

1996: The Geodetic Science and Surveying Program continues within the new department, but independently of Civil Engineering programs.

1998: B.S. in Surveying is changed to B.S. in Geomatics Engineering.

2002: The Geodetic Science Program celebrates 50 years at OSU with the W.A. Heiskanen Symposium in Geodesy.

2005: The majority of Geodetic Science faculty moves to the Department of Geological Sciences (College of Mathematical and Physical Sciences).

2006: The Department of Geological Sciences becomes the School of Earth Sciences with divisions, one being the Division of Geodesy and Geospatial Science.

2009: The Geodetic Science Graduate Program moves entirely to the School of Earth Sciences. The Division name changes to Division of Geodetic Science. Geodetic Science in engineering becomes a track, Geoinformation and Geodetic Engineering, in the Civil Engineering Graduate Program.