Team UV

Planetary nebula NGC 2818, which resides within a star cluster in the Milky way, as captured by the Hubble Space Telescope on January 15th, 2009.   Photo Credit: Wikipedia.org

Prompt: Highly interdisciplinary engineering teams are put to work in the design of space telescopes and many fields of engineering must be considered, including (but not limited to): classical mechanics, fluid mechanics, materials science/engineering, heat transfer, electromechanical systems, etc. If you were the head engineer for the design team of the next NASA space telescope, what would be the top 3 design areas/systems that you would choose to put the
greatest focus into developing/improving and why. Remember, there are financial, manufacturing, practical, and theoretical limits to be considered; hence you can never really design the perfect system, some sacrifices must be made, and perhaps the systems you would like to focus on might be impractical to target.

1. Vibration Control: Vibrations can cause the image to blur; however, this could be controlled through material selection and strategic placement of hardpoints along the mirror backing in order to manipulate the vibration modes, node locations, and wave interference, resulting in less vibration.  Viscous dampers could also be used to damp out vibration introduced by power supply, boosters, mirror actuators, etc.

2. Thermal Control: Thermal strain within focal optics can cause significant blurring; this can be accounted for with cryocoolers tied to the optics through thermal straps.  The cryocoolers use thermodynamic cycles to cool components to cryogenic temperatures, pulling heat from the optics, through the thermal straps, and eventually sinking it out to heat dissipation controls.  Current cryocoolers can maintain temperatures down to about 3K which approaches a limit, thus future research could focus on more efficient cryocoolers (rather than lower temperatures) to allow more cryocoolers or other thermal controls for the same power needs.

3. Materials Science: Generally, the more mirrors, the more image blur with respect to telescopes, thus most research efforts focus on use of monocrystalline materials, which are about as optimal as they can be currently without a major revolution in materials forming/manufacturing techniques.  Research could then be conducted with respect to improving control in material forming/processing to better tailor mechanical properties (i.e. rigidity) more precisely.