Definition of radial velocity in English:

radial velocity

noun

Astronomy
  • The velocity of a star or other body along the line of sight of an observer.

    • ‘By taking very careful measurements of the ‘radial velocities,’ the researchers were able to determine precisely how each star was moving in relation to the galaxy.’
    • ‘With this tool, researchers can measure changes in the radial velocity of a star to an accuracy of 1m a second.’
    • ‘They are part of a large programme aimed at measuring accurate radial velocities for sixty stars for which a temporary brightness ‘dip’ has been detected during the OGLE survey.’
    • ‘Most of them are detected by indirect methods, based either on variations of the radial velocity or the dimming of the star as the planet passes in front of it.’
    • ‘The first truly threedimensional largescale survey of the universe was made by Valérie de Lapparent and colleagues, who published radial velocities and positions for a large sample of galaxies.’