Jason DavisMar 22, 2018

Funpost! The transportation of humans to foreign planets

Welcome back for another Thursday Funpost! I recently got an email from a high school student named Chris (not his real name) looking for experts to talk about about human missions to Mars for his senior project. I offered a tentative yes.

Then Chris replied with 11 comprehensive questions. Chris! This isn't expert input, this is you asking me to do your homework! 

There are different schools of thought from scientists and science communicators on how to handle inquiries like this. In short, we have to weigh the potential benefit to the requester(s) against the burden to our time. Normally I would have said no to Chris, because I knew the answers would take me a solid hour, and I'm not convinced my reply would be more beneficial than sending him to Google for his own research.

In Chris's defense, it's probably a challenge for newbies to sift through the rhetoric on a subject like humans-to-Mars, and if I answer him, I'll have a good starting point for future requests. It also just so happened that I didn't have a topic for this week's Funpost! The format was supposed to be throwbacks, but let's expand things a little bit to help Chris out. That's service journalism, folks. But be warned, this is a certified Funpost, so my answers are going to be pretty casual. 

Pressurized rovers on Mars
Pressurized rovers on Mars An artist’s concept depicting long-range exploration on the surface of Mars using pressurized rovers.Image: NASA (Rawlings)

1. Currently, what barriers, either biological or technological, inhibit the transportation of humans to foreign planets (e.g. Mars)?

Foreign planets! I love that phrase. It sounds like the title of an old sci-fi novel: Adventure to the Foreign Planets

The main barriers are neither biological nor technological; they are money and politics. If the White House and Congress cut NASA a blank check for Mars right now, and no one cared about which companies were used, or what NASA centers did the work, humans could be on Mars in 10 years. But in reality, it's more complicated than that

Biologically, there's radiation, but I get the sense no one can agree on how dangerous the trip would actually be. It may be that with some precautions like increased shielding or a solar storm shelter, it's pretty doable. Maybe we just have to accept that if you go to Mars, you'll end up with an increased risk of cancer in the long run. Technologically, the big challenge is entry, descent and landing (EDL). Mars' atmosphere is annoying! It's too thin to completely slow down an inbound spacecraft, but too thick to ignore in terms of heat shielding. NASA's Jet Propulsion Laboratory can land a literal ton on Mars using the insane Skycrane method, but humans are heavier. I'll be really interested to see if SpaceX truly has Mars EDL figured out for their next rocket, the BFR. 

2. How will technology have to adapt in the future to make the first manned missions to nearby planets feasible?

First of all, don't call them "manned." It's not your fault if you didn't know this; we've been using manned since the beginning of the space age, and people still use it today. But NASA doesn't say manned anymore. It's just not an inclusive word for half of the world's population. Try crewed, or get creative and use something like "meat-occupied."

Basically for Mars you need all the technology that keeps astronauts alive on the ISS, only you need it to work really, really reliably. If the toilet breaks halfway to Mars, you can't fly up new parts in a month or so, or just abandon ship (a broken toilet sounds awful, by the way). Also, breathing is important! You don't want your carbon dioxide scrubbers going belly-up in interplanetary space, for example.

3. What contributions have you made towards making a manned Mars mission feasible in the near future? How will these contributions eventually be useful to these first manned missions?

Chris, I get the feeling you sent this to some people making actual contributions to Mars missions. You gotta proofread your emails after you cut and paste, dude! My contribution is reporting on what's happening. Oh, also, my employer is the world's leading space advocacy organization. Join us! I feel strongly about those contributions, but I'm not actually building spaceships or anything.

4. What other celestial bodies may be accessible to humans in the near future (for research or colonization) once a Mars mission has been successful?

For starters, the Moon is hot right now. Well, only the half currently in the sun; the other part gets really cold. Ha! Anyway, we're going back to the Moon before Mars. Some people say living on the Moon will help us prepare for living on Mars. That's true for some technologies, but for others, there's not always a clear step-by-step relationship.

5. As of right now, how will humans sustain themselves on Mars for extended periods of time? In other words, what sources of food, energy, and shelter could astronauts aboard the first manned missions use to survive?

Well, right now, aboard the International Space Station, we rely entirely on food from Earth. We might be able to grow crops in the Martian soil, but it has these annoying toxins called perchlorates that we'll have to deal with. For energy, we'll probably use solar at first, and maybe nuclear power later. For shelter, your starter choices are bringing your own habitats, using expandable habitats, or 3D-printing stuff using the Martian soil, if you want to get really fancy.

6. As of right now, could humans ever return to Earth after several years of transit to Mars?

Sure! The Planetary Society proposed a concept to have humans orbiting Mars in 2033, and yes, these theoretical humans would come home.

7. How long would it take for humans to create a self-sustaining, completely independent colony on Mars?

I think it depends on how you define "self-sustaining." Can we trade with Earth for natural resources that don't exist on Mars? To use one example: copper. Does it exist on Mars, and if so, can we mine it? I wrote a story several years ago about a proposed open-pit copper mine here in Southern Arizona, and I learned questions like this are complicated. Copper is everywhere, but not surprisingly, people don't like the idea of having a giant mine in their backyard. To answer how we'd become self-sustaining, you need to consider all the hidden stuff like copper that you use in your daily life, and either answer how we'd find it on Mars or figure out how to do without it.

8. Is terraforming Mars's atmosphere a viable option in its current state? If not, when will it be a viable option?

Nukes, Chris, nukes! You continuously detonate nuclear weapons over each of Mars' poles to sublimate the ice, creating a runaway greenhouse effect that warms the planet. I see no challenges with this proposal and expect it be implemented soon.* 

9. Are there any terrestrial organisms that might be able to survive on Mars' surface?

In 2012, some German researchers showed lichens and cyanobacteria might be able to survive there, and that's why we sterilize spacecraft before they go. The Germans were a little slow on this realization, to be honest; Jeff Goldblum had it figured out back in 1993.

10. Are there any humanitarian or economic concerns behind sending a mission to Mars?

Do you mean, is it wise to spend billions of dollars sending humans to Mars when we have plenty of problems back on Earth? Most people in the space community believe exploring space and saving the world shouldn't be an either-or proposition. We can do both! Plus, space programs provide demonstratable sociological and technological benefits for Earth. 

Now, if you're talking about the societal structure of a future Mars colony, I think there are some legit concerns. I used to think we'd branch out into the cosmos and build a utopian society like on Star Trek. Now I think that view was naive; there's no guarantee we won't export Earth's inequality baggage elsewhere and end up with Babylon 5 Downbelow subclasses. (All credit to Casey Dreier, our policy director, for turning me into a Babylon 5 fan.)

11. How much does a trip to Mars with humans and the necessary parts to society cost?

No one knows! NASA has avoided doing cost estimates for this sort of thing ever since an infamous 1989 study under President George H. W. Bush predicted a cost of $500 billion over 20 to 30 years. That price tag has been generally debunked, but it doesn't help that people like me bring it up from time to time.

*That last sentence was a joke, Chris. Don't put that in your research.

Do you have ideas or questions you'd like answered for a future Funpost? Email me at [email protected]!

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