15 August

1993: On 15 August 1993, after more than three years of efficient and successful operations, communications with ESA's scientific satellite Hipparcos were terminated.

The Hipparcos satellite, a purely European undertaking, and the first space experiment dedicated to the highly accurate measurements of star positions, distances and space motions, was launched in August 1989. Targeted for an operational lifetime of two and a half years, more than three years of high-quality star measurements were eventually accumulated, and all of the original scientific goals of the mission fully accomplished.