Redshift calibration is a research area in astronomy that focuses on accurately measuring and correcting for the redshift of astronomical objects. Redshift refers to the phenomenon where the light from a distant object is shifted towards longer wavelengths due to the Doppler effect, indicating the object is moving away from Earth. In order to accurately determine the distance and velocity of these objects, astronomers must calibrate or correct for the redshift measurements. This involves comparing the observed redshift of known objects, such as galaxies or stars, with their actual distance and velocity. By establishing a calibration curve or equation, astronomers can then apply this correction to redshift measurements of other objects to obtain more accurate distance and velocity measurements. Redshift calibration is important in various areas of astronomy, such as studying the large-scale structure of the universe, determining the expansion rate of the universe, and tracking the movements of galaxies and clusters of galaxies. Improvements in redshift calibration techniques can lead to more precise measurements and a better understanding of the universe.