What does absorption refer to in terms of light interaction with targets?

Absorption refers to the process where light is taken in by a material rather than being transmitted or reflected. When light interacts with a target, certain wavelengths may be absorbed, meaning that energy from the light is transferred to the target material, often resulting in a temperature increase or a change in the material's physical or chemical properties. This is crucial in various applications, such as remote sensing, where understanding how different materials absorb light can help identify substances based on their spectral signatures.

The other interactions, like light passing through a surface (transmission) or being reflected back (reflection), involve different processes and outcomes that do not reflect the absorption phenomenon. Scattering pertains to the redirection of light without absorbing it, which is also a different aspect of light interaction that does not involve the energy being retained by the target. Therefore, the definition of absorption aligns perfectly with the concept of light being trapped and held by a target.