What is the primary difference between a pixel and a spectral band?

The primary difference between a pixel and a spectral band lies in their definitions and functions in remote sensing. A pixel is the smallest unit of a digital image that represents a specific area on the Earth's surface. It reflects the values of the light that is captured by a sensor for that specific area, contributing to the overall image from which analysis can be performed.

In contrast, a spectral band refers to a specific range of wavelengths that a sensor measures. Each spectral band captures information about how different materials reflect or emit energy at those particular wavelengths. For example, different bands may be sensitive to visible light, infrared, or other parts of the electromagnetic spectrum.

This distinction is crucial for interpreting remote sensing data, as the combination of pixel information and spectral bands allows analysts to identify and understand different features and materials on the Earth's surface. Pixels provide the spatial context, while spectral bands give insight into the composition and characteristics of those features based on their electromagnetic signatures.

Other options do not accurately describe the relationship or fundamental characteristics of pixels and spectral bands, as they either confuse definitions or attribute functions incorrectly.