The Travels of the JWST Mirror Segments

What a long, strange trip...

Good morning, everyone.

I was doing further research into the James Webb Space Telescope, and I discovered that the mirror segments made quite a journey in the process of their creation.  As part of their amazing fabrication, the 18 segments of the main mirror make 14 stops to 11 different places in eight states around the U.S. to complete their manufacture. You could even call it ‘High-mileage High-tech’, especially because ‘High-kilometerage’ sounds stupid [thumbs nose in the direction of Canada]. The image at the top is a map of the route each mirror segment would take, and resembles nothing as much as a diagram of the path of a pinball during play that hits all of the drop targets, lights up all the specials, and gets an extra ball.

The process starts at the beryllium mines at the Topaz-Spor Mountains of Utah, and ends up at Northrop Grumman, Redondo Beach, California for integration of the assembly with the spacecraft. Here is a short video about the journey:


I’d really like to see how they packed up and shipped the segments from place to place, but I could only find where one company shipped 5 segments, and it didn’t provide much detail. I’d like to see the shipping containers that were used, especially in the later stages of fabrication.

Later on, I’ll have a post that takes a much closer look at what goes into making the JWST’s mirrors.

Here’s a list of the journey-by-numbers on the map:

  1. From Brush Wellman Inc.’s mine in the Topaz-Spor Mountains of Utah, beryllium powder is mined and shipped to Brush Wellman’s facility in Elmore, Ohio, where it is sifted and purified into an extremely uniform optical mirror blank.
  2. To Axsys Technologies in Cullman, Alabama, where the back of each “blank” is made into a honeycomb structure to lighten it, and they also provide general shaping of the front of the mirror.
  3. To L3 Communications, Tinsley Laboratories in Richmond, California, where segments are ground and polished to a smooth and exact shape, then tested at room temperature.
  4. To Ball Aerospace & Technologies Corp. in Boulder, Colorado, where mounts and actuators are attached to the mirror segments, and vibration and optical testing are done.
  5. To the X-ray and Cryogenic Facility (XRCF) in Huntsville, Alabama, where Ball conducts cold (cryogenic) vacuum optical testing of segments in order to generate a map of cold distortions provided as a map to Tinsley Labs.
  6. Back to Ball Aerospace & Technologies Corp., Boulder, Colorado, to remove mount and actuators.
  7. Back to L3 Communications, Tinsley Laboratories at Richmond, California.Where each mirror is fine-tuned by polishing in the opposite of the surface error values derived from the XRCF’s super-cold testing. Now, distortion that occurs in space-cold should actually perfect the mirror.
  8. Back to Ball Aerospace & Technologies Corp., Boulder, Colorado, to clean mirror segments to prepare for coating.
  9. To Quantum Coating, Inc., Moorestown, New Jersey, where gold is evaporated over the segments in vacuum chamber and it forms a very thin coating on the smooth mirror surface.
  10. Back to Ball Aerospace & Technologies Corp., Boulder, Colorado, to reassemble the mirror segments with mount and actuators. Final vibration testing is done.
  11. Back to the XRCF in Huntsville, Alabama, where Ball performs final cryogenic acceptance testing on the segments.
  12. To NASA Goddard Space Flight Center, Greenbelt, Maryland where  personnel  from  the  ITT  Corporation,  Rochester,  New  York,  assemble  the  telescope  and attaches it to the instrument module. Acoustic and vibration tests are performed.
  13. To NASA Johnson Space Center, Houston, Texas for final cryogenic testing of the whole telescope.
  14. To Northrop Grumman, Redondo Beach, California for integration of the assembly with the spacecraft and sunshield.
  15. To the Guiana Space Centre, Kourou, French Guiana, for lift-off on an Ariane 5 rocket…and the beginning of the Webb telescope’s million-mile journey to its final destination in space!



NASA’s “Journey of the Webb Mirrors”


  • Nice. A lot of semiconductor products go through quite a worldwide trip from sand to consumer door step.
    One processor I used a few years back did something like quarry (unknown location) –> USA -> France –> Cyprus –> Philippines –> France –> Hong Kong (before it was returned to China) –> China –> Hong Kong –> Regional distribution center –> local distributor –> retailer –> consumer.