QUESTION:
If all of the thrusters (RCS) quit right after the shuttle "leveled-off"
after launch, would it's nose stay level with the horizon as it orbits
the earth (like an airplane flying straight and level), or would the
nose eventually rise until the nose is pointing out to space, and the
tail is pointing down at the earth (gravity gradient effect).  I guess
what she's asking is whether the shuttle attitude drifts or stays the
same as it orbits the earth (assuming no thruster inputs).

ANSWER from Ed Mango on January 28, 1998:
Thanks for your question, your student asked a very intelligent
question.  A vehicle in low earth orbit with no attitude control will
drift to a position where the heaviest part of the vehicle is the
closest to the center of the earth.  That is normally called the gravity
gradient attitude.  For the Space Shuttle that would be tail towards the
earth.  Since there is no real air, only some small amount of atomic,
there is no flow in which the wings can produce lift or drag.  Therefore
aerodynamics will play no real role in the equation.  Attitude control
would then be required to keep the nose of the vehicle pointed in the
velocity vector.  A question for your class to think about would be:  If
gravity gradient keeps the heavy part of the vehicle closest to the
earth, what would a Sun Synchronic orbit look like?  (Hint: The Mir
starts with this type of orbit every time the Mir computer shuts down.)
Good Luck !!