Throwback: NASA Completes Webb Telescope Center of Curvature Pre-test
An archival image from October 2016.
In November 2016, engineers and technicians working on the James Webb Space Telescope successfully completed the first important optical measurement of Webb’s fully assembled primary mirror, called a Center of Curvature test.
Taking a “before” optical measurement of the telescope’s deployed mirror is crucial before the telescope goes into several stages of rigorous mechanical testing. These tests will simulate the violent sound and vibration environments the telescope will experience inside its rocket on its way out into space. This environment is one of the most stressful structurally and could alter the shape and alignment of Webb’s primary mirror, which could degrade or, in the worst case, ruin its performance.
Webb has been designed and constructed to withstand its launch environment, but it must be tested to verify that it will indeed survive and not change in any unexpected way. Making the same optical measurements both before and after simulated launch environment testing and comparing the results is fundamental to Webb’s development, assuring that it will work in space.
Read the full story: go.nasa.gov/2fyqLwE
Image credit: NASA/Chris Gunn
Self-Portrait of NASA’s James Webb Space Telescope Marks Critical Test by NASA’s James Webb Space Telescope
What appears to be a unique selfie opportunity was actually a critical photo for the cryogenic testing of NASA’s James Webb Space Telescope in Chamber A at NASA’s Johnson Space Center in Houston. The photo was used to verify the line of sight (or path light will travel) for the testing configuration.
During Webb’s extensive cryogenic testing, engineers checked the alignment of all the telescope optics and demonstrated the individual primary mirror segments can be properly aligned to each other and to the rest of the system. This all occurred in test conditions that simulated the space environment where Webb will operate, and where it will collect data of never-before-observed portions of the universe. Verifying the optics as a system is a very important step that will ensure the telescope will work correctly in space.
Read the full story: go.nasa.gov/2xRmVY7
Image: Ball Aerospace optical engineer Larkin Carey is reflected in the James Webb Space Telescope’s secondary mirror, as he photographs the line of sight for hardware used during an important test of the telescope’s optics. Credit: Ball Aerospace