QUESTION: 
What would happen if NASA lost track of the Pathfinder? What could you do to
find it again?

ANSWER from Pieter Kallemeyn on February 17, 1997:
If we lost track of Pathfinder, we would do what is called a 'sky search', 
where we point the ground antenna's at the most likely spot in the sky and 
slowly scan the area around it in a outward spiral.  Eventually, we would 
pick it up again within a matter of a few hours at most, providing of course 
that the spacecraft is healthy and transmitting a signal.  

Once we regain contact, we would investigate to determine why we lost track 
of the spacecraft and try to correct measures to ensure it doesn't happen 
again.