Description: Any pattern that propagates through space with little or no change is a wave. Fourier's theorem shows how such travelling patterns can be understood as the sum of "elementary waves", each a regular pattern of repeating maxima or minima akin to a mathematical sine function. The distance between each maximum of such a regular elementary wave and the next maximum is called the wave's wavelength. Several kinds of wave phenomena play a role in astronomy. Electromagnetic radiation, our main source of information about astronomical objects, is a wave phenomenon, and in some observation techniques that wave nature plays an important role. Sound waves play a role for the interior structure of stars. Gravitational waves have emerged as a new source of information about astronomical objects.

Related Terms:

• Frequency
• Visible Spectrum
• Gravitational Waves

Term and definition status: This term and its definition have been approved by a research astronomer and a teacher

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