[FPSPACE] losing ISS's balance

[Keith Gottschalk]

       If the ISS CGMs are overwhelmed by something as incredibly minute as sublimating ice from two spacesuits, that implies a sobering lack of a margin of safety.  True, there are attitude rockets / jets for emergencies - but one does not want to be sacrificing scarce propellant that must be expensively hauled up. 

   Also, if ISS, goodness forbid, had to operate for say a year in humanless mode, it would be important for it to have adequate gyros / flywheels to toil away every time somethng bumped it off-centre (even a naughty leaking thruster). Perhaps future space stations should have a 3rd system, in addition to flywheels & thrusters.

   That is, ye olde wire coils around the hull that some of the early satellites used. Then, swiching on the current in Earth's magnetic field gives you the torque to nudge your space station until once again your PVs are perpendicular to the sun, or whatever you need. Of course this is a very weak nudge that might require days to get your space station tilted back to the right oritentation. But it is still a useful back-up system for just-in-case situations.

  At least until the Earth's magnetic field becomes too weak to be useful, before it again strengthens in 2000 yrs time when our magnetic S pole completes popping up on your side of the globe!  :)