Questions about the astrometric satellite of the European Space Agency, launched in 1989 and operated until 1993.

Hipparcos is a satellite that was used to make the Hipparcos catalog of 118,000 stars with unprecedented precision. The European Space Agency (ESA) launched it in 1989 and it operated until 1983, see https://www.cosmos.esa.int/web/hipparcos

The satellite was named for the ancient Greek astronomer Hipparchus and is also an acronym for HIgh Precision PARallax COllecting Satellite.