QUESTION:
Does the Periodical Table "hold up" on Mars, that is to say, are the number
of elements, which we have thought to be truely finite, actually infinite. 
Or to put it better, are there any new elements on Mars that we have not
discovered yet because we are on Earth?

ANSWER by Smart Filter on August 5, 1997:
The 'Periodic Table of Elements' is a universal table. It holds for all
places in the Universe. Most elements in the table up to and including
Plutonium can be found on earth (the only execption is Neptunium). No
elements beyond Plutonium are found on earth. A number of these, up to
element 103 Lawrencium, have been made by man, either in a lab, or in a
nuclear explosion.

The elements that do not exist on earth are not likely to be found on Mars
either. Most of them decay in two or more other elements. Their half life
times are too short for any traces to be left on a planet. This does not
mean that these elements could not exist in the universe. They would exist
for a very short period of time only, for instance after the explosion of a
star as a supernova. During those explosions, conditions exist under which
many elements can be synthesised, even some elements that could not be
created on earth during nuclear explosions, or in a particle accellerator.

For a great web site about the periodic table of elements, point your
browser to http://users.boone.net/yinon/default.html

ANSWER from Bruce Jakosky on December 1, 1997:
Mars is composed of the same elements as is the Earth (and as is
everything else in the universe), and the surface is made up of the
same types of minerals.  It may be possible to find places on Mars that
have some elements in greater abundance than they are found on the Earth,
but the cost of transporting them back to the Earth would be very high.

The reason we are going to Mars has more to do with our desire to explore
the world around us, to understand the other planets in our solar system
and the other worlds in our galaxy, and to search for life elsewhere.
It is the information that we get that is of the most value.