On This Day: The Hubble Telescope’s First Servicing Mission

By Lewis Brown on

Whilst our focus at Atik Cameras primarily covers ground-based astronomy through our specialist cameras, it is impossible to ignore the impact that the Hubble Space Telescope has had on astrophotography since its launch in 1990. With this in mind, we are celebrating the fact that on the 9th December in 1993, a servicing mission to repair the Hubble Space Telescope was declared successful1 . This servicing mission to repair the primary mirror was the first time astronauts had visited the telescope in orbit2, and was carried out by astronauts Story Musgrave and Jeff Hofman who completed a space walk of 7 hours and 21 minutes to finalise the mission 1.

About The Servicing Mission

The mission was necessary due to an aberration in the primary mirror of the observatory was discovered shortly after the deployment of the Hubble Space Telescope in 19903. This defect affected the clarity of telescope which resulted in early images from the Hubble being less than optimal…

Before and after service mission repair Before and after the service mission comparison image of the galaxy M100 Photo Credit: NASA[/caption]

In order to repair the mirror, an instrument named the Corrective Optics Space Telescope Axial Replacement (COSTAR) was installed 4. The phone-box sized COSTAR placed 5 pairs of corrective mirrors in front of the Faint Object Camera, the Faint Object Spectograph and the Goddard High Resolution Spectograph 4.

In addition to correcting the primary mirror defect through the COSTAR, the astronauts on this mission also installed the Wide Field Planetary Camera 2 (WFPC2). This improved upon the original WFPC through its significantly improved ultraviolet performance, more stringent contamination control and advanced detectors4.

Continued Service

This successful servicing mission in 1993 was the first of five such missions on the Hubble Space Telescope, with the final one occurring in 2009 and installing improvements which are set to allow the Hubble Space Telescope to overlap with its successor 2, the James Webb Space Telescope, which is set to launch in 2021 and be the premier observatory of the next decade as it will study “…every phase in the history of our universe, ranging from the first luminous glows after the Big Bang, to the formation of solar systems capable of supporting life on planets like Earth, to the evolution of our own Solar System.”5

No further servicing missions are scheduled to repair or replace equipment on the Hubble Space Telescope although a dedicated team of engineers and scientists continue to work to keep Hubble operational for as long as possible6.


  1. BBC – Astronauts repair Hubble Telescope, 1993
  2. NASA – About – Hubble Servicing Missions
  3. NASA – Hubble’s Mirror Flaw
  4. NASA – The Hubble Space Telescope – Servicing Missions
  5. NASA – About James Webb Space Telescope
  6. NASA – About – The Hubble Story