Climate of Mars cold while those in the North are short and warm. It is now thought that ice accumulated when Mars' orbital tilt was very different from what it is now. (The axis the planet spins on has considerable "wobble," meaning its angle changes over time.) A few million years ago, the tilt of the axis of Mars was 45 degrees instead of its present 25 degrees. Its tilt, also called obliquity, varies greatly because its two tiny moons cannot stabilize it like our moon. Many features on Mars, especially in the Ismenius Lacus quadrangle, are thought to contain large amounts of
Sword and planet Mars" by Edgar Rice Burroughs originally serialized by "All-Story" in 1912 as "Under the Moons of Mars". The genre predates the mainstream popularity of science fiction proper, and does not necessarily feature any scientific rigor, being instead romantic tales of high adventure. For example, little thought is given to explaining why the environment of the alien planet is compatible with life from Earth, just that it does in order to allow the hero to move about and interact with the natives. Native technology will often break the known laws of physics. The genre tag "sword and planet" is constructed to