ABSTRACT
Mathematical modelling of the shape of the Earth and computational methods to measure its shape parameters is known as geodesy. In other words geodesy models the overall shape of the Earth through mathematical modelling. The physical properties exhibited by Earth such as its gravity field, magnetic field, polar and Keplarian motion etc. forms the basis for modelling the shape of Earth. In recent years direct measurement of the diameter of the Earth by focusing the laser beams from the satellite gives a credible accuracy of the estimations arrived by geodesic estimations. A glimpse of various applications of geodesy and its principles in measuring the physical parameters of Earth is given to make the reading of the subject interesting. A formal definition of geodesy can be the mathematical modelling of the shape of Earth and measurement of its geometrical parameters by modelling the physical phenomena exhibited by Earth such as its magnetic and gravity fields. The direct measurement of the shape of Earth is performed by focusing of laser beams fitted on the satellites revolving around the Earth. In other words geodesy is modelling, measurement and study of the physical shape of the Earth, its geometry through laser range finder, magnetic and gravity field modelling.
