QUESTION:
What is the most expensive piece of equipment on the MGS?

ANSWER from Charles Whetsel on February 25, 1997:
The most expensive piece of equipment on the MGS spacecraft is one of our
scientific instruments called the Thermal Emission Spectrometer.  It is a
very complicated type of infra-red mapping instrument that can not only
take images of the surface and atmosphere of Mars during day and night but
can also take an atomic spectrum of the area which it is observing.  These
spectra allow our scientists to understand what kinds of elements and
minerals are in each area of the picture.  When the instrument was first
built for the Mars Observer probe (which was lost) it cost almost $25
million dollars to design and build.  For Mars Global Surveyor, we dusted
off the blueprints and were able to build a replacement for less than half
of what the original cost.

Charles Whetsel