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Re: Re: AO-40: why did they have to rotate it?

>Now how does this situation affect the eventual (?) move to 3 axis
>stabilization using the momentum wheels?  If I understand things correctly,
>even under momentum wheel control, the bird will still experience periods of
>non-optimum squint angle in order for the solar panels to catch the sun.

True, though in theory we should be able to tolerate a few hours of bad 
solar angle to give optimal squints, then swing back to recharge the batteries.

>Now will the additional, unfolded panels help to decrease periods of bad sun
>angle since you have more panels out there and so thereby we have a better
>point to earth?

I'm not quite sure if I understand your point, but I think the answer is 
no.  In part we have to try to stay within solar sensor ranges.

>Finally, what is the status and plan of moving to spin up the momentum
>wheels and open the panels?  Is it ever going to happen or are we just too
>unsure of the condition of the bird to risk it?

As soon as we have a final timetable, I'll sure pass it along.  It's not a 
matter of uncertainty about the spacecraft.  It's a matter of testing a lot 
of software, making sure all the contingencies like the mystery effect and 
protracted eclipses are covered, and that we can get back to spin mode if 
we need to. The original plans for 3-axis mode were based on a much higher 
inclination....  Some of the software routines will need to be loaded in 
the spacecraft and tested in bits and pieces.  Others can be tested in 
ground simulations.  This is all under active development, but we do not 
want to rush it or back ourselves into a corner from which we cannot retreat.

  Stacey E. Mills, W4SM    WWW:    http://www.cstone.net/~w4sm/ham1.html
    Charlottesville, VA     PGP key: http://www.cstone.net/~w4sm/key

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