Inside the James Webbs Space Telescope

NAFEMS welcomed Mike Menzel from NASA as a Keynote presenter at the 2023 World Congress. Mike is the mission system engineer for The James Webb Space Telescope- a project that has captured the world's attention as the largest optical telescope in space. The infrared telescope, sometimes called JWST or Webb, launched from ESA's spaceport in French Guiana on December 25, 2021.

Now usually, when someone starts explaining the role of systems engineering to me at a simulation and modelling conference, I wince as I know I'm about to get shown a Vdiagram, swiftly followed by phrases like "functional requirements" with a side course of "MBSE" thrown in. But this isn't what we got. Instead, the delegates were treated to one of the best, real, practical examples showing how modelling & simulation and systems engineering are inexorably linked. Mike isn't a keynote at a NWC23 because he is a simulation engineer- he is the customer of the simulation engineer. The models and predictions made by teams of simulation engineers allow him to do his job.

The engineering challenges associated with the James Webb telescope are enormous. The design is subjected to many competing constraints. It is mass limited by the launch vehicle that will deliver it into orbit. It requires dynamic stability for the optics to work. It "sees" the universe in the IR spectrum, so it must remain cool (by cool, we are talking about keeping 3 tonnes of equipment below 55 degrees kelvin) etc. etc. etc. The observatory measures about the size of a tennis court when deployed, but it also has to fit inside a launch vehicle 5 meters in diameter. When the platform is delivered into orbit, it unfolds as 107 separate mechanisms are released, all of which must work flawlessly, or the mission (and 25 years' worth of work) will be all for nothing.