Reducing Space Station Down Mass

Consider the resupply situation for the International Space Station.  Every few months or so for the past ten years supplies have been sent to the space station aboard the space shuttle or Russian Progress cargo ships at a cost of approximately $100 per pound. 

Used equipment, packing materials, and the perfectly good, working cargo ship are then discarded to burn up in the atmosphere.  All because there is no safe way to store or recycle the materials, some of which could become extremely hazardous in the confined volume of the station.  Also, the lack of maintenance and limited lifetime of certain components (especially seals, pyrotechnics and the fuel systems) mean that the cargo ships would be unsafe. 

Careful rethinking and redesign with the goal of eliminating all possible “down-mass” operations would make inhabiting space much more cost effective.  Designing equipment to be disassembled into reusable material or components inside the station and designing the vehicles themselves for permanent attachment to the growing station would provide much needed additional space as well as shielding and safety from orbital impacts. 

If cleverly done, this could provide the basic research into techniques for building really large structures in orbit.  Questions about orbital boost and decay, dynamic stability, structural strength, modes of oscillation, etc., could all be studied.  But not if the design requires that we continue to regularly discard tons of mass that we already paid to put into orbit.