Mars is the fourth planet from the Sun and the second-smallest
planet in the Solar System, after Mercury. It can easily be seen from
Earth with the naked eye, as can its reddish coloring. Named after the
Roman god of war, it is often referred to as the "Red Planet" because
the iron oxide prevalent on its surface gives it a reddish appearance.
Mars is a terrestrial planet with a thin atmosphere, having surface features reminiscent both of the impact craters of the Moon and the valleys, deserts, and polar ice caps of Earth. Its two polar ice caps appear to be made largely of water. The rotational period and seasonal cycles of Mars are similar to those of Earth, as is the tilt that produces the seasons. Mars has two small and irregularly shaped moons, Phobos and Deimos.
There are ongoing investigations assessing the past habitability
potential of Mars, as well as the possibility of extant life.
A Mars a Day recalls the vintage covers of the well-remembered, the rarely read, and the totally obscure science fiction books boasting a
Martian theme...
