The spectral region of the electromagnetic radiation which passes through the atmosphere without much attenuation is known as:

• A. Ozonewindow
• B. Atmospheric window
• C. Blackwindow
• D. Absorption window

Answer: (B)

Regions where electromagnetic radiation can pass through the atmosphere with little attenuation are called atmospheric windows. This happens because the atmosphere’s main absorbers—water vapor, carbon dioxide, ozone, and others—have relatively weak absorption at specific wavelengths, so both solar radiation reaching Earth and terrestrial or astronomical radiation escaping to space experience minimal loss. These windows are crucial for ground-based observations and satellite sensors, and they occur at several parts of the spectrum, including portions of visible, near-infrared, and certain microwave bands. Other terms like ozone window or a generic absorption window aren’t the standard way to name this phenomenon.