What is remote sensing?

Remote sensing is fundamentally defined as the acquisition of information about an object or phenomenon without making physical contact. This method employs various technologies, such as satellites, aircraft, or drones, equipped with sensors that capture data across numerous wavelengths. For example, remote sensors can gather information about the Earth's surface by detecting electromagnetic radiation reflected or emitted by features like vegetation, water bodies, urban areas, and even atmospheric conditions. The advantage of this technique lies in its ability to collect extensive data over large areas while minimizing the need for direct physical interaction with the subject, which is often impractical or impossible in many scenarios.

In contrast, measuring physical properties in laboratories or analyzing samples on-site involve direct contact with the object or phenomenon being studied. These methods provide valuable data, but they do not encapsulate the essence of remote sensing, which focuses on non-contact data acquisition. Observing objects through direct interaction falls outside the scope of remote sensing, as it requires physical presence rather than the remote techniques employed through sensors. Similarly, obtaining immediate results by analyzing samples on-site lacks the expansive data-gathering capability that remote sensing offers, as such approaches are typically limited to localized studies rather than broad geographic assessments.