|1977||American congress approves funding for Hubble.|
|1981||Space Telescope Science Institute (STScI) begins operations in Baltimore, Maryland.|
|1984||Space Telescope-European Coordinating Facility (ST-ECF) begins operations in Garching, Munich.|
|1990||Launch: Shuttle Discovery (STS-31) launched on 24 April 1990.
Hubble deployed on April 25, 1990.
|Spherical aberration discovered in the Hubble primary mirror, 25 June, 1990.|
|COSTAR approved: The creation of a complex package of five optical mirror pairs to rectify the spherical aberration in Hubble's primary mirror.|
|1993||First Servicing Mission (STS-61) launched on 2 December, 1993 (Endeavour).
COSTAR corrective optics installed, replacing HSP (High Speed Photometer).
WFPC2 (Wide Field and Planetary Camera 2) replaced WFPC1 (Wide Field and Planetary Camera 1).
|1997||Servicing Mission 2 (STS-82) launched on 11 February, 1997 (Discovery).
STIS (Space Telescope Imaging Spectrograph) replaced FOS (Faint Object Spectrograph).
NICMOS (Near Infrared Camera and Multi-Object Spectrograph) replaced GHRS (Goddard High Resolution Spectrograph).
|1998||HST Orbital Systems Test (HOST - STS-95) launched on 29 October, 1998 (Discovery). The HOST mission was flown to test new technologies to be used in Hubble on the Third Servicing mission and beyond.|
|1999||Servicing Mission 3A (STS-103) launched on 19 December, 1999 (Discovery).
Replacement of gyroscopes.
General maintenance (no science instruments replaced).
|2002||Servicing Mission 3B.
Installation of ACS (Advanced Camera for Surveys).
Installation of NICMOS Cooling System (NCS).
Installation of new Solar Panels.
|Servicing Mission 4.
Installation of WFC3 (Wide Field Camera 3).
Installation of COS (Cosmic Origins Spectrograph).
STIS and ACS repaired.
Gyroscopes and batteries replaced.
Soft Capture Mechanism installed.
NOBLs (New Outer Blanket Layers) installed.