Introduction to earth observation / remote sensing

What is it in a nutshell?

Remote sensing can be defined as a way of collecting data to get information about an object without the instrument used to collect the data being in direct contact. The platforms that can be used for this purpose are airborne or space-borne and include manned aircraft, unmanned aerial vehicles (UAV) and satellites (Figure 1). The object of remote sensing may be a well-defined natural or anthropogenic target such as a pipeline, or it may be a natural, operational or administrative area, such as a lease region.

What is RS Schematic showing remote sensing from the range of platforms covered within this document. Satellites can potentially image very large areas with repeat observations whenever their orbits allow, while aircraft are capable of supporting observations with more detail and flexibility, albeit with more limited coverage.


Remote sensing technology has been available for over a century, developing in parallel with manned flight, but the capabilities of the technology have become increasingly powerful during the 21st century, largely as a result of the following:

  • Development of new types of operational remote sensing platforms, including very small satellites (<10 Kg) operated in large constellations that are able to generate observations of the surface very frequently, and UAV (with miniaturised sensors), which are becoming very common for flexible near-surface imaging.
  • Declining costs of remote sensing components and, in the case of satellites, launches, which has led to increasing competition and innovation, to the benefit of the market.
  • An increasing number of key remote sensing datasets that are publically available.
  • Increasing availability of value-added information services built on large quantities of data and advanced digital technologies (such as sophisticated algorithms, cloud computing and communication networks), resulting in more directly actionable intelligence for users.

The result of these developments is that remote sensing is now increasingly well aligned with commercial and operational drivers, and has attracted growing awareness of capabilities among the general public and non-governmental organisations (NGO).