Space exploration financing, we've discussed the money it would take to get to deep space and questions about whether it's worth it. Space exploration technology, we've showed you the potential vehicles and rockets that could take people far, far away.
But what about space exploration psychology? Six people living on Hawaii's Mauna Loa Volcano are part of $1.6 million study in how the brain can handle the confines of living on Mars.
RACHEL CRANE, CNN CORRESPONDENT: It's crazy that you guys have been living in this dome for eight months. Six of you in here.
NEIL SCHEIBELHUT: Are you calling me crazy?
CRANE: But that's actually why these six crew members were chosen for this special mission, to see if they would go crazy.
UNIDENTIFIED FEMALE: It definitely has that potential.
CRANE: I was one of the first civilians they saw in months.
It's pretty tiny.
That's because they were stuck living inside the small dome, pretending to be on Mars, except Mars is the top of this dormant volcano in Hawaii.
Some say this is the most Martian-like environment we have here on earth. It's isolated. It's desolate. It's rocky. It's cold. I mean, I truly feel like I'm on another planet.
They lived here because NASA needs to figure out a major problem, if the mind can handle a trip to deep space.
DR. LAUREN LEVETON, NASA SCIENTIST: These missions are incredible undertakings. They're unprecedented in terms of distance, duration and confinement.
CRANE: We don't know how it's truly going to impact our brains.
LEVETON: Yes, exactly. We really want to be able to quantify this risk.
CRANE: And that's where the HI SEAS mission comes in.
KIM BINSTED, HI SEAS INVESTIGATOR: The goal of this mission is to look at crew cohesion and performance. We want to see how we can select people and then support them so they can do long duration space mission without —
CRANE: Going crazy.
BINSTED: Yes, basically.
CRANE: There have been similar experiments, but HI SEAS is one of the longest. And the first to focus solely on the coed mission to Mars.
SCHEIBELHUT: So, we have to wear this sociometers while we were awake and they would like measure interaction.
CRANE: So, those are the things that would measure how close you are to some of your other crew members, see who likes each other and who doesn't like each other.
SOHIE MILAM: Yes, how loud your voices when you're talking to someone.
CRANE: Right, right.
MILAM: — if there was strain, you're possibly having a heated discussion.
SCHEIBELHUT: That never happened.
A Mars mission could last over a year. So, researches studied how the HI SEAS crew behaved during this extended period of time, in this very confined space.
Is there any place in this habitat where you had any privacy at all?
MILAM: Visual privacy, you can go into your room and close the door, but there's absolutely no sound privacy at all.
CRANE: But it's not just how the crews get along.
BINSTED: The data we're getting out is giving NASA engineers information about how much water crews used, how much food they eat, what kinds of food they eat, how much energy they used, how much space they need.
UNIDENTIFIED FEMALE: This is the largest room in the house.
CRANE: The crew members selected for this mission are astronaut-like as possible, chosen for their education and temperament. But even they had a hard time.
SCHEIBELHUT: I had to try different things. I had to like, OK, well, maybe if I just go in my room and like stay away from people for a while, that doesn't work.
CRANE: But if we want to make it to another planet, we need to figure out how to deal with these feelings of anxiety, depression, even boredom.
MILAM: We played board games about five nights a week.
CRANE: Do you guys like bored a lot so you needed the board games?
SCHEIBELHUT: Well, yes. Movies and TV shows and board games were about the only social activities we had.
CRANE: And NASA psychologists say that a very important part of keeping us happy is food.
So, this is where you guys did all your cooking.
CRANE: But this is not your typical cooking. I mean, you guys were dealing with freeze dried food here.
CRANE: Nothing really fresh.
MILAM: You can always find someone making something in here. So, it's kind of the most social.
SCHEIBELHUT: Stepping into the legs.
CRANE: And whenever they went outside to simulate space walks, they actually wore a spacesuit.
CRANE: Having gone to this experience, would you still go to Mars?
CRANE: Would you go to Mars?