Mars the planet is a unique world: a little like Earth, a little like the Moon, but entirely a world unto itself. Mars the television show is similarly one of a kind, an unusual amalgam of scripted science fiction and serious science documentary. The fictional part of the story begins in 2033, when the spacecraft Daedalus lands on the Red Planet to establish the first human outpost there. But as so often happens in space exploration, things don’t go exactly as planned…

Season 1 of Mars was an intriguing experiment in world-building: The scripted part of the series painted a plausible portrait of how a crewed Mars mission might unfold, accidents and all, while the documentary portion grounded the story with commentary by marquee-name experts including astronaut Scott Kelly and SpaceX rocket guru Elon Musk. If the two halves didn’t entirely mesh, they at least bolstered each other. The interviews provided a reality check for the storytelling, while the dramatic elements emphasized what is really at stake. Season 2, debuting now, admirably builds on that foundation.

In its second season, Mars raises the stakes by spiking the story with new competition between Olympus Town, the research-focused Martian outpost, and a new commercial competitor, Lukrum Industries, which is committed to exploiting the planet for profit. This plot line cleverly mirrors the current efforts by both NASA and SpaceX to develop viable plans for a human landing on Mars. Enveloping this conflict are two even larger issues: a search to find and understand life on Mars, and a long-term project to terraform the planet into a place more suitable for habitation.

The added plot elements and expanded cast breathe fresh life into Mars. In the hands of new showrunner Dee Johnson, the documentary and fictional elements merge more seamlessly than before, and the storyline feels both more urgent and more grounded in genuine human emotion. At its best, Mars now rises to the grandeur of The Expanse–a show that similarly grapples with the politics of a settled, partially terraformed Mars, albeit from a much different, farther-future perspective.

To gain some insights into the real and fictional worlds of Mars, I spoke with author and space enthusiast Andy Weir, best known as the creator of his own Mars-based story, The Martian. Weir appears on Mars as an expert in the documentary sections, and has a lot of deeply considered thoughts about how to take some of our fictional ideas about the Red Planet and bring them into reality. An edited version of our discussion follows.

Andy Weir talks about the Mars series at a Comic Con panel in New York City. (Credit: National Geographic)

What was it like participating in somebody else’s vision of the future of Mars?

I had no involvement in the creative side of the series; I’m in the nonfiction segments only. My personal experience of that was awesome. The producers would come in and interview for about six hours, and it’s really cool because I can ramble on about space as long as anybody wants. They would ask specific questions, they’d say, “Here is some stuff we want to talk about.” It was fun, because I could infer some of the plot elements from the questions they asked.

A key plot element in Mars is an effort to terraform the planet–to make its climate more like Earth’s. Is that really feasible?

It’s absolutely feasible, but I don’t think it’s feasible with today’s technology. The main thing you have to do is heat the planet up a little bit, not even all that much. Mars has a huge amount of carbon dioxide in solid form at the poles and mixed in the soil. If you can start to melt that–or rather sublimate it back into gas–then you’ll have a runaway greenhouse effect, the kind we’re trying to avoid here on Earth.

As more carbon dioxide adds to the atmosphere, the atmosphere will trap more heat, which will sublimate more carbon dioxide, which will trap more heat, and so on. Eventually you get to the point where you have a fairly thick atmosphere that holds heat in. Then the water on the planet will start to melt, and you will start to have bodies of water. Getting the right temperature and atmospheric pressure, that’s doable. The hard part would be maintaining the correct atmospheric oxygen. But even if you partially terraform–even if you still need to wear a breather mask but you don’t need a space suit–that would be a pretty big win.

What about other ideas for warming the planet, such as building giant factories to pump out CFCs or other intense greenhouse gases?

Ultimately, you have to add heat. Any way you can add heat, whether it’s nuking the poles or adding significant greenhouse gases, could work. But if you’re going to add greenhouse gases to Mars, the best one to add is carbon dioxide because it’s already there. You don’t have to do anything to make it, like you do with CFCs. Methane is a much better greenhouse gas than CO2, but you’d have to manufacture it, too. But with carbon dioxide, you can just start that runaway greenhouse effect and set it in motion. That’s what happened to Venus [where things are now a little too toasty, at an average temperature of 850 degrees F].

Moderator Corey S. Powell (who, me?) discusses the future of the Red Planet with the Mars cast and showrunner Dee Johnson, at center left. (Credit: National Geographic)

How could you oxygenate the atmosphere of Mars on a fairly short timescale?

Plants—the same way Earth oxygenated its atmosphere. Plants have the benefit of making more plants, so you have this doubling, doubling, doubling process. If you end up with large bodies of water on Mars and you can introduce algae that works there, then it’ll grow and bloom. It will be cranking out huge amounts of oxygen.

You would need to initiate and then maintain a biosphere on Mars, and that’s hard. Earth took 4.5 billion years to where it is now! If you’re in a hurry, that makes it a lot harder. Even going all-out it would take centuries, realistically. Centuries before we’re ready to start, and the process itself would take centuries more. Then again, maybe in a few centuries we’ll have technology that can really speed it up.

The Mars series also grapples with the ethics of terraforming. What is your view–do we have the right to remake a whole planet?

I disagree with a lot of the planetary scientists, because I believe Mars has no life and never had life. If I’m right on that, we have zero ethical responsibility to preserve any part of Mars. It’s a bunch of rocks–who gives a crap? If there is life on Mars, that changes things, but not much. By the time we have the technology to terraform Mars, we would also have the technology to preserve. It would be like, “OK, here’s a bunch of native Martian life. Let’s make sure we don’t render any of it extinct.” We’d take part of the planet,  dome it off, and make sure the terraforming doesn’t affect that; or we’d have an artificially generated original Mars environment that we keep things in—a little Mars zoo.

But I honestly believe the issue is not going to come up at all, because I don’t believe Mars has now, or has ever had life. Early on, Mars had an oceanic, heavy-atmosphere environment. It changed from that to what it is today over hundreds of millions of years. Evolution can move faster than that. If there was life on Mars during those early days, it would have evolved to adapt in the current environment, because the change was so gradual. There’d still be life all over the place, and that’s not what we see.

What would it take to convince scientists that there is not any life on Mars?

That’s a really good question. You can never prove a negative! But here’s an example. We have long since given up on the idea that there’s life on the Moon, and all we’ve ever done on the Moon is bring back samples from six manned missions. Now scientists are finding that that there’s water on the Moon! Does that mean there’s life? No, still no life on the Moon. We’re comfortable with that assumption. I think it’s just a matter of time [before we reach the same conclusion about Mars].

The issue is that Mars feels so much more like Earth than the Moon. It does have air, and it has some water. It makes people wonder. But I think a lot of the theories of life on Mars just stem from people really wishing there was life on Mars. Of course it would be so awesome to find! It would raise, and then immediately answer, so many questions. Did Mars infect Earth with life? Did Earth infect Mars with life? Or was there an independent genesis on Mars?

If it’s an independent genesis, that means the universe is probably littered with life—just playing the odds. And if it isn’t, that’s really interesting just to know that planets can infect each other with life.

What do you think about the prospects for life on Europa or Enceladus?

Same thing. I think it’s unlikely because they’re so distant that they don’t have enough energy coming from the Sun [to drive chemical reactions]. We have so little data about Enceladus or Europa that I’m less confident, whereas with Mars we’ve sent probes. We’ve dug down. We’ve looked for life, we’ve looked at things microscopically, and we’ve found nothing ever.

Is commercial exploration of Mars really plausible, the way we see happening in season 2 of the Mars series?

I don’t think so. Whatever it is you plan to exploit from Mars can certainly be found easier and cheaper on Earth. The only benefit to Mars, from an exploitation standpoint, is colonizing. The only way you’ll get an economy there is by having people there to need an economy. And I think it’s going to be a long time before anyone colonizes Mars, because there’s no economic incentive.

If we get to the point that we have spacecraft that are really really cheap–like if it’s as cheap to get into low-Earth orbit as it is to fly to Europe today–and if you can get to Mars in a couple weeks or even a couple of days, then I think people will colonize Mars. Humanity colonizes shit; it’s what we do. We go and we expand into other lands, and by God if there’s already humans there, we kill them and just keep on going.

So if it’s not unreasonably expensive to go to Mars, people will go there just for the hell of it. Then you have people there, and that creates the beginning of economic need, and it grows from there. But I think all that’s going to happen on the Moon long before it happens on Mars.

Michio Kaku, one of the experts interviewed in Mars, talks about space colonies as “Plan B” in case something happens to Earth. What do you think about that argument?

I often hear people say, and I wholeheartedly agree, “There is no Planet B.” The idea that we would give up on this planet and go to a different one is absurd. Whatever problems Earth’s environment has, it’s easier to fix them than it is to colonize Mars–way, way easier. It would be easier to create devices all over the world that pull carbon dioxide out of the atmosphere and put it into dry ice bricks that we store in some airtight chamber [to undo global warming] than colonizing Mars. It would be cheaper, too. What is easier, developing a system to deflect large asteroids or colonizing Mars? There is no problem on Earth that’s harder to solve than colonizing Mars.

The last time we had an extinction-level event on Earth was 65 million years ago. I’m willing to gamble that we’re not going to have another in the next thousand years. Within a thousand years, I believe space travel will become trivial enough that we will have already expanded to Mars. So I don’t feel like the “We need to preserve humanity” argument creates an immediate urgency. Within a billion years, I suspect we will have been able to develop enough technology to deal with the brightening Sun. When you’re arguing that we have a threat that exists at astronomical timescales, that means that we’re not really in that big a hurry.

A meeting of minds and miners: In the first episode of season 2 of Mars, the scientists prepare to share the planet with a new commercial prospecting crew. (Credit: National Geographic/Dusan Martincek)

What propulsion technology will help open up solar system exploration so it can be more like in Mars or even The Expanse?

I like ion technology. It’s far better than chemical propulsion. It all comes down to energy storage. If you can store a lot of energy in small space, you can eventually get ion engines that are acceleration particles so fast that they gain relativistic mass. Imagine you’re throwing protons out the back of your ship. OK, now imagine you’re throwing protons out so fast that their mass is times three due to special relativity. Now you’re getting a lot more propulsion; you’re getting even more bang for your buck.

Pretty much everything ends with energy storage. A big chunk of uranium is a really really good dense energy storage if you have a nuclear reactor. Both the US and the former Soviet Union have put nuclear reactors into space, so it’s not like we haven’t done it. There are a lot of people for whom the word “nuclear” automatically means we shouldn’t do it, but I think that’s s surmountable problem. We’ve been shooting out RTGs [radio-thermal generators that make electricity from a plutonium heat source] without incident. The Curiosity rover is powered by an RTG, nobody cared about that.

The main concern is the safety of transporting it. People want to know, what if something goes wrong with that launch? If you want to have a nuclear powered spacecraft–a full-on nuclear reactor with a stockpile–you start by putting all of the hardware in space without the nuclear fuel. Then you have a separate launch that is just the nuclear fuel, and it is guarded all to hell, so much that if the entire rocket disintegrates, the fuel will fall to Earth and still not breach. This will be expensive; we’re sending up a whole rocket with a 50 ton payload to put maybe one kilogram of fissile material up there. But this thing could literally blow up at any point during launch and the payload would fall from space to Earth and still it would not break open.

How does it feel watching somebody else’s story about humans on Mars?

Oh, I love it. I want to be clear: The way I write is just my style of writing. That does not mean it’s the only form of entertainment that I enjoy. I know it doesn’t sound right from a hard-sci fi dork like me, but I love Dr Who. I love soft sci-fi. I’m a big Star Trek fan. Star Wars, also. I’m more of a Trekkie than a Star Wars guy, but more of a Whovian than either of those.

What I don’t like is sci fi that falls into the uncanny valley, where it’s kind of accurate but also not. In Star Trek, you’ve got warp drive—I’m fine with that. If you’re going to say, here’s something that violates all known laws of physics, I’m like, that’s fine, as long as it does it consistently. The Enterprise can go Warp 9. But then it should not take you very long to go from Mercury to Earth. There was an episode of classic Trek where they have to get from Mercury to Earth and they are cruising along and cruising along. I’m like—what are you doing? Even at Warp 1 it’ll take you about 8 minutes! But Mars is really good in that regard. It respects its rules.

New episodes of Mars appear Mondays at 9PM on the National Geographic Channel.