Mars is the 4th planet out from the sun. Sites in this category deal with this planet, and its moons.
Only sites dealing specifically with Mars or its system in general should be placed in this category.
Life on Mars is a category devoted to speculative or scientific investigation of the possibility of life on Mars.
Life on Mars is a category devoted to scientific investigation of the possibility of life on Mars. Pretty dry stuff, for the most part.

If you are submitting a site that contends that the government is covering up obvious evidence of life on Mars, or a site that presents "proof" of intelligent life on Mars, please submit to the UFO Conspiracies page.