Whenever Mark goes out on the surface, he gets a brutal reminder of how alone he truly is. The Hab provides a certain degree of comfort—although he still can't communicate with Earth, the mere presence of this man-made building reminds him that there's a home waiting for him. Unsurprisingly, the barren landscape of Mars has the opposite effect.

Sometimes, the best scientific solution to a given problem is to simply use what Mother Nature gave us. After all, our bodies are finely-tuned pieces of technology that took hundreds of thousands of R&D to perfect. That sure beats the pants of an iPhone.

Mark never gets used to life on Mars. The Hab helps him stay sane, providing him a small connection with his life back on Earth, but even that is fleeting. Sooner or later, Mark is going to need to explore more of the Martian surface—that is, if he's up to the challenge.