QUESTION:
If there are such adverse tempature changes on Mars, shouldn't there be ice
and/or frost developing on the equipment from Earth or the surface of the
planet? And if so, surely there is oxygen contained within this moisture.

ANSWER from Jack Farmer on July 22, 1997:
During the Viking missions frost was observed  to precipitate from the
atmosphere in winter, covering the surfaces of rocks near the lander, and
presumably also the lander itself.  The same is likely to also happen again
for any spacecraft landed on Mars, and particularly at higher latitudes.
There is very little oxygen in the present Martian atmosphere, only about
0.13%. The atmosphere mostly contains carbon dioxide (>95%). Thus, Martian
frosts are likely to contain CO2 or water ice than molecular oxygen.

Jack D. Farmer, PhD.
NASA Ames Research Center