NASA Video: Space Station/Space Shuttle docked in orbit

On Jun 8, 11:01*am, "David E. Powell"
wrote:
Not Michael Bay, this is the real deal....

http://www.nasa.gov/multimedia/video...ia_id=93985151


I was struck by the different positioning of the major solar
arrays ... perhaps it was only necessary to "feather" half of them
during the Soyuz undocking? Or did free drift require the arrays to
face in different attitudes?

/dps

On 06/28/2011 12:41 AM, snidely wrote:
On Jun 8, 11:01 am, "David E.
wrote:
Not Michael Bay, this is the real deal....

http://www.nasa.gov/multimedia/video...ia_id=93985151


I was struck by the different positioning of the major solar
arrays ... perhaps it was only necessary to "feather" half of them
during the Soyuz undocking? Or did free drift require the arrays to
face in different attitudes?

There are many independent requirements that have to be satisfied in
solar array positioning, so the final positioning chosen is not
necessarily intuitive.

Among the requirements is to avoid partial longeron shadowing. The
longerons are the struts running down the middle of the solar arrays. If
a solar array shadows one side of the longerons but not the other,
differential thermal expansion could cause the array to buckle.

On Tue, 28 Jun 2011 18:58:15 -0500, "Jorge R. Frank"
wrote:


There are many independent requirements that have to be satisfied in
solar array positioning, so the final positioning chosen is not
necessarily intuitive.

Among the requirements is to avoid partial longeron shadowing. The
longerons are the struts running down the middle of the solar arrays. If
a solar array shadows one side of the longerons but not the other,
differential thermal expansion could cause the array to buckle.

Thanks, Jorge!

/dps