In 1989, the first space mission to understand positions, distances, motions, brightness and colors of stars was launched. Four years later, ESA's Hipparcos achieved its goals and ceased operations

In August 1989, European Space Agency launched Hipparcos, the first space mission dedicated to measuring the positions, distances, motions, brightness and colors of stars. The research was conducted for astrometry.

Hipparcos was launched by an Ariane-4 rocket. The pioneering space experiment was dedicated to the precise measurement of the positions, parallaxes and proper motions of the stars. The mission's lifetime was around 2.5 years.

The aim was to measure the five astrometric parameters of around 120,000 primary program stars to a precision of around 2 to 4 milliarcsec. It also aimed to know the astrometric and two-color photometric properties of around 400,000 additional stars (the Tycho experiment).


In March 1993, the operations were ceased after the fulfillment of the mission goals. NASA also provided some critical support to the mission. In December 2013, a successor mission to Hipparcos called Gaia was launched ESA.

The Hipparcos helped to predict the impacts of Comet Shoemaker-Levy 9 on Jupiter, identify stars that will pass close to the Sun, establish the distances of stars possessing planets, discover that the Milky Way is changing shape, identify a group of stars that invaded our Galaxy when it was young, altered the cosmic distance scale, making the Universe bigger and younger and confirm Einstein's prediction of the effect of gravity on starlight.