Which statement best describes infrared radiation in the context of thermal sensing?

• A. It is not used in remote sensing
• B. It only measures color
• C. It measures visible light
• D. It detects heat emission

Answer: (D)

Infrared radiation in thermal sensing is the heat energy that objects emit as infrared light, which sensors can detect to infer temperature differences across a scene. Because hotter areas emit more infrared than cooler ones, infrared imaging reveals heat patterns even in darkness and through some atmospheric conditions. This makes infrared a powerful tool in remote sensing, since it captures thermal information rather than color or visible brightness. It does not measure color or visible light, and its primary use is to detect heat emission, not to sense visible characteristics.