Mars – our knowledge of the surface
QUESTION: What is known at present about the surface of the planet Mars?
Answer
I imagine that you would like to know what the state of knowledge is about the surface of
Mars at present after the visit of the recent USA spacecraft.
The surface of Mars is
dusty with major fissures (some many hundreds of kilometres long) and a number of extinct
volcanoes – some of them very large.
Mars has a mean surface temperature of
about – 63 degrees centigrade (210 K) and an atmosphere composed of 95% carbon dioxide
and 3% nitrogen. The atmosphere also contains 210 parts per million of water
vapour.
The surface is rocky and dusty and scoured by dust storms in which the
wind speed may reach 30 m/s. The soil is rich in both magnesium and iron. Geological
analysis of rocks shows that Mars is a much more geologically developed planet than was
previously thought. Different areas of the planet showing quite different
development.
There are many images of Mars on the Internet – NASA has a wealth
of material, including a planetary fact sheet, and the following site has some impressive
photographs as well as other
detail:
www.nasm.si.edu/research/ceps/etp/mars/surface/html
A VERSION IN WORD IS AVAILABLE ON THE SCHOOLPHYSICS USB