Introduction to Geodesy: Geoids, Ellipsoids, and Coordinate Systems

Mapping the Earth accurately requires a deep understanding of its true, irregular shape. This course introduces you to the core principles of geodesy, the science that underpins all modern mapping, GPS, and geographic information systems (GIS). You will progress from basic concepts of Earth measurement to understanding how we model the planet's surface using reference ellipsoids and geoids. By mastering these spatial foundations, you will be able to interpret coordinate reference systems and work confidently with geospatial data. What you'll learn: 1. Learn the fundamental definitions and history of geodesy as a mathematical science. 2. Understand the physical difference between the geoid, reference ellipsoids, and the actual Earth surface. 3. Explore how coordinate reference systems and datums are established and maintained. 4. Analyze the relationship between ellipsoidal heights and orthometric heights. 5. Apply geodetic principles to modern GPS, GNSS, and GIS mapping workflows. 6. Practice converting and interpreting spatial coordinates through written step-by-step exercises. The course begins with foundational definitions of Earth's geometry and gravity fields before guiding you through the practical application of datums and coordinate transformations. Designed for beginners in GIS, surveying, civil engineering, and geography, this text-based course requires no prior background in advanced geophysics. Start reading today to build a rock-solid foundation in geospatial science.