QUESTION:
What was the most expensive part of Pathfinder? Why?

ANSWER from Donna Shirley on December 3, 1997:
Well, It's really hard to say which was the most expensive part, because it
depends on how you define part.  The computer system which included all the
software, the computer, and all the parts that allowed the computer to talk
to the parts of the spacecraft that it controlled was $30 million.  Since
the total cost of the spacecraft was $150 million, the computer system was
probably the most expensive single part.

But the toughest job was the landing system - the airbags, radar sensor that
sensed when the spacecraft was close to the ground, and the rockets that
slowed everything down after the airbags were inflated.  The structure of
the spacecraft also was much harder than we expected.

So you really need everything to make the system work and it's hard to say
what was the most expensive.

The rover was relatively cheap, the whole thing was $25 million.

Donna Shirley