Why do scientists study space using multiple wavelengths of light?

• A. Some wavelengths reveal the same information as others.
• B. Different wavelengths reveal different information about celestial objects.
• C. Infrared is always better than visible light for space imaging.
• D. Visible light alone provides the full picture.

Answer: (B)

Different wavelengths reveal different information about celestial objects because light interacts with matter in wavelength-dependent ways. Light in the visible range can show us surface temperatures and chemical fingerprints through spectral lines, but dust can block and obscure what lies behind it. Infrared light can pass through dust and expose cooler objects and warm dust, revealing star-forming regions and planets that are hidden in visible light. Ultraviolet highlights very hot, energetic processes and young, massive stars, while X-rays expose high-energy phenomena like accreting black holes and supernova remnants. Radio waves trace cold gas, magnetic fields, and various cosmic emissions, offering a view of processes invisible in shorter wavelengths. By combining data from many parts of the spectrum, scientists assemble a much fuller, more accurate picture of celestial objects and events than any single wavelength could provide. Hence, studying space with multiple wavelengths is essential, rather than relying on infrared alone or on visible light alone.