Hipparcos was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry. This permitted the first high-precision measurements of the intrinsic brightnesses, proper motions and parallaxes of stars. Each star selected for study was visited about 100 times over four years.


The resulting Hipparcos Catalogue, a high-precision catalogue of more than 118,200 stars, was published in 1997. Hipparcos' follow-up mission, Gaia, was launched in 2013.



Peranso makes use of the Hipparcos Catalogue, which is further described here.