Happy Birthday, HST!

posted by: Damon Diehl

It’s been twenty years since the Hubble Space Telescope (HST) was launched on April 24, 1990. The Connecticut Post has a really nice article describing how the engineers who designed HST still remain emotionally attached to the project.

As is well known, when the first images arrived from HST, it was discovered that the primary mirror was flawed. The flaw was caused because of an error in the reference optics used by Perkin-Elmer to test the mirror. Rochester, NY has two notable connections to fixing this problem. First, Eastman Kodak’s Commercial and Government Systems Group (now a part of ITT Space Industries) had independently manufactured a back-up mirror for the HST. Unfortunately it was not feasible to replace the primary mirror while the HST was in orbit. Second, Jim Fienup (now a professor at the University of Rochester Institute of Optics) developed “phase retrieval” computer algorithms that were able to diagnose and digitally correct the images Hubble was sending back. This information was later helpful in designing the Corrective Optics Space Telescope Axial Replacement (COSTAR) that was added to Hubble to correct the spherical aberration.