Remote sensing involves the determination of the position of points on, above and below the earth's surface without traveling to and touching that point. This method of surveying involves an advanced knowledge of the shape of the earth and its movement (called Geodesy) and knowledge of Photogrammetry techniques.
Principally, this involves using satellite imagery, airborne laser scan results, GPS and other tools to create a mathematical model of the region in question.
Remote sensers rely upon statistical analysis to ensure reliability of their results and work with very large data sets.
This is a specialist area of surveying and demands quite a different skill set to the Engineering or Cadastral surveyor.
Students at university level and Diploma level are introduced to Geodesy and Remote Sensing in their undergraduate courses.