Page "Marshall Space Flight Center" Paragraph 33

The Hubble Space Telescope was launched in April 1990, but gave flawed images.

It had been designed at MSFC, but used a primary mirror that had spherical aberration due to incorrect grinding and polishing by the contractor.

Facilities were not available at that time for ground-based ene-to-end optical testing, so the defect was not found until the telescope was in orbit.

The design was such that repairs were possible, and three maintenance missions were flown in Shuttles during the 1990s.

Another servicing mission ( STS-109 ) was flown on March 1, 2002.

Each mission resulted in considerable improvements, with the images receiving world-wide attention from astronomers as well as the public.