blueshift
/ˈbluːʃɪft/
noun
- The change in light from a star or other object moving toward an observer, making it appear more blue than it actually is.
- When a star moves closer, its light shows a blueshift.
- Astronomers observed a blueshift in the light from the approaching galaxy.
- The blueshift told scientists that the star was moving toward Earth.
Antonyms