The shuttles deployed a number of deep space astronomy instruments into orbit. Other astronomy studies also used instruments mounted in the shuttle payload bay and on free flying, retrievable platforms.

The primary orbital astronomy payloads are summarized below.

CGRO was launched on a two-year mission to search for the high-energy celestial gamma ray emissions, which cannot penetrate Earth's atmosphere. GRO was the second of NASA's four Great Observatories. The Hubble Space Telescope [STS-31] was the first. GRO science instruments were Burst and Transient Source Experiment (BATSE), Imaging Compton Telescope (COMPTEL), Energetic Gamma Ray Experiment Telescope (EGRET) and Oriented Scintillation Spectrometer Experiment (OSSE).

[STS-37] (1991)
Wikipedia Compton Gamma Ray Observatory
Gunter's Space Page CGRO
Encyclopedia Astronautica GRO

Astronomical observatory designed to operate above the Earth's obscuring atmosphere to observe celestial objects at ultraviolet, visible and near-infrared wavelengths. When conducting an observation, the space telescope is rotated into the proper orientation, then pointed to the star it is to view and locked in place. It is the first spacecraft specifically designed for on-orbit servicing.

* Launch Deployed in a 380 statute-mile (611.5 km) Earth orbit.

* Servicing Mission 1 Restored the HST vision, marred by spherical aberration, with the installation of a new main camera and a corrective optics package. The flight also brought instrument upgrades and new solar arrays to the telescope.

* Servicing Mission 2 The older Goddard High Resolution Spectrograph and the Faint Object Spectrograph were exchanged for the Space Telescope Imaging Spectrograph (STIS) and the Near Infrared Camera and Multi-Object Spectrometer (NICMOS). In addition other existing hardware was replaced with upgrades and spares.

* Orbital Systems Test (HOST) A platform carried experiments to validate components planned for installation during the third Hubble Space Telescope servicing mission and to evaluate new technologies in an earth orbiting environment.

* Servicing Mission 3A NASA officials decided to move up part of the servicing mission that had been scheduled for June 2000 after three of the telescope's six gyroscopes failed. Three gyroscopes must be working to meet the telescope's very precise pointing requirements. A gyro failed in 1997, another in 1998 and a third in 1999. All six gyroscopes were replaced and a new computer was installed that dramatically increased the computing power, speed, and storage capability of HST.

* Servicing Mission 3B Installation of a new science instrument, the Advanced Camera for Surveys (ACS), new rigid solar arrays (SA3), a new Power Control Unit (PCU) and an experimental cryocooler for the Near Infrared Camera and Multi-Object Spectrometer (NICMOS). Shuttle Columbia also re-boosted HST to a higher orbit.

* Servicing Mission 4 Installed two new instruments, the Cosmic Origins Spectrograph and the Wide Field Camera 3. The mission also replaced a Fine Guidance Sensor, six gyroscopes, and two battery unit modules to allow the telescope to continue to function at least through 2014. The crew also installed new thermal blanket insulating panels to provide improved thermal protection, and a soft-capture mechanism that would aid in the safe de-orbiting of the telescope by an unmanned spacecraft at the end of its operational lifespan.

[STS-31, 61, 82, 95, 103, 109, 125] (1990, 1993, 1997, 1998, 1999, 2002, 2009)
Wikipedia Hubble Space Telescope,  Space Telescope Science Institute
Gunter's Space Page HST
Encyclopedia Astronautica HST