QUESTION:
I am wondering why it only took 211 days for this trip to Mars but a manned
flight to Mars would take years?

ANSWER from Steve Wall on July 15, 1997:
Trajectory design is a very deep subject, and the real answer to your
question depends on when you want to go and a lot of other things. There is
no easy relationship between the time it takes to get there and the mass you
want to send, and of course sending humans involves other questions - how
much mass for a human flight depends on how long the people need to stay,
which also depends on what return opportunities there are, etc., etc.  The
only easy statement is that a flight bearing humans has many more
constraints on it.

A manned spaceship would certainly mass more than several thousand kilograms
- if it didn't have to carry fuel to return.  The Pathfinder mass is
available at http://mpfwww.jpl.nasa.gov/