Written by the Fiveable Content Team • Last updated August 2025
Written by the Fiveable Content Team • Last updated August 2025
Definition
Blueshift is the phenomenon where light or other electromagnetic radiation from an object moves towards shorter wavelengths. This typically indicates that the object emitting the light is moving closer to the observer.
Redshift is the phenomenon where light or other electromagnetic radiation from an object moves towards longer wavelengths, indicating that it is moving away from the observer.
A dark or bright line in an otherwise uniform and continuous spectrum, resulting from emission or absorption of light at a specific wavelength by a substance.