Radiaalinopeuksia

Radiaalinopeuksia refers to the component of an object's velocity that is directed along the line connecting the observer to the object. In simpler terms, it is the speed at which an object is moving directly towards or away from you. This is distinct from the tangential velocity, which is the speed at which an object moves perpendicular to the line of sight.

The concept of radial velocity is fundamental in various fields of science, particularly astronomy. Astronomers use radial velocity measurements to determine if celestial objects are approaching or receding from Earth. This is often achieved by observing the Doppler shift of light emitted by these objects. A redshift indicates that the object is moving away, while a blueshift indicates that it is moving towards the observer.

Measuring radial velocities allows scientists to study the motion of stars within galaxies, the orbits of planets around their stars, and the expansion of the universe. For instance, the radial velocity of a star can reveal its participation in stellar streams or its orbital path around the galactic center. In exoplanet detection, the radial velocity method is a key technique, where the slight wobble of a star caused by an orbiting planet's gravity is detected through changes in the star's radial velocity. This method has been instrumental in discovering thousands of exoplanets. The units for radial velocity are typically meters per second (m/s) or kilometers per second (km/s).