Yes, it is true that in story-telling, the conflict generally produces a struggle leading to a sequence of events resulting in suspense or excitement, although this conflict can take different "shapes" and develop as the characters try to solve it.
Martians or Aliens, oppose to Zombies and other monsters, cause a unique fear because of the fact that outer space scares us. I mean, why shouldn't it? Space is a cold desolate place bigger than we could possibly imagine, whereas the earth, where we live, is mostly explored. That's not even including all the rumors about Alien cover-ups by the government.
<span> classification/division I think....Hope this helps!! </span>
