Glossary term: Refraction

Description: Refraction is the way that a wave – and, specifically, light – changes direction as it passes from one medium into another. The magnitude and direction of the change depends on the "indices of refraction" of the two media, a relation that is encoded mathematically in Snell's law of refraction. The way that light passes into a piece of glass can be used to create a lens, which bundles parallel light rays – such as the light of a distant star – falling onto the lens. This is the main effect used in constructing refracting telescopes. Refraction also depends on the wavelength of the infalling light, a fact that can be used as in a prism, to separate light by wavelength into its constituent elementary colors – which is important for documenting and examining spectra.

Related Terms:

See this term in other languages

Term and definition status: This term and its definition is still awaiting approval

The OAE Multilingual Glossary is a project of the IAU Office of Astronomy for Education (OAE) in collaboration with the IAU Office of Astronomy Outreach (OAO). The terms and definitions were chosen, written and reviewed by a collective effort from the OAE, the OAE Centers and Nodes, the OAE National Astronomy Education Coordinators (NAECs) and other volunteers. You can find a full list of credits here. All glossary terms and their definitions are released under a Creative Commons CC BY-4.0 license and should be credited to "IAU OAE".