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Why is infrared astronomy useful for observing objects hidden by dust?

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Telescope Aerial view of the Keck Observatory's twin domes, which are opened to reveal the telescopes. Keck II is on the left and Keck I on the right.

Infrared astronomy is a vital tool for observing celestial objects that are otherwise hidden from view because interstellar dust effectively blocks shorter-wavelength radiation, such as visible light.12

While dust grains scatter and absorb visible light, infrared radiation—which has longer wavelengths—is able to flow around these dust particles. This property allows astronomers to detect objects that are obscured by dense clouds of gas and dust, such as stars in the process of formation within nebulae or the energetic regions at the centers of galaxies. By observing in the infrared, investigators can peer through these opaque regions to study phenomena that would remain invisible to optical telescopes.12