Context: JWST is considered un-repairable in its current L2 location for a number of reasons:
- Diagnosis is difficult since JWSR has no “selfie” capability. This makes planning for any repair mission (crewed or robotic) problematic.
- Distance and radiation exposure are vastly beyond the experience of crewed missions
- JWST was not designed to be serviceable so repair would likely be complex and require the flexible talents of a crewed mission, perhaps multiple missions.
- Rocket exhaust could damage optical surfaces.
- JWST cannot transfer itself closer to Earth for repair since this would mean pointing its optics towards the sun for the burn.
Proposal: Built a robotic “tugboat” with thrusters which are positioned to be safe for the optics. Have the tugboat dock with JWST using the launch mount or docking ring. The tugboat would then transfer JWST to an Earth/Moon L1 orbit. The Gateway/Artemis resources would be available for diagnosis and repair. This would avoid the expense and radiation exposure of a dedicated crewed repair mission to L2. Once repaired, the “tugboat” could reposition JWST at Sun/Earth L2, and remain with JWST in case a repeat mission is needed. The tugboat could also be used for end-of-life decommissioning, extending JWST service life.
Transfer of JWST from SEL2 to EM halo orbits or “Gateway” orbit using low-energy trajectory is within the delta-v budget of typical earth-SEL2 missions. Is the inter-manifold transfer of JWST between Sun-Earth L2 and Earth-Moon L1 within the capability of existing propulsion systems?
All components of JWST can tolerate room temperature, but the optics are capable of focusing Sunlight, Earthlight and Moonlight to destructive intensity if the image of the radiating body falls on the secondary mirror. A purpose-built “tugboat” could give independent control of attitude and thrust direction.
Question: With independent control of attitude and thrust direction, could JWST be kept pointing in a “safe” direction (for instance at the celestial pole) during the proposed transfer and repair?