Mars Settlers Shift to Enclosed Domes as Terraforming Logistics Fail

Colonizing Mars — Isaac Arthur

Isaac Arthur

Prohibitive interplanetary transport costs and severe nitrogen scarcity make full planetary terraforming impractical, forcing Martian civilization to rely on localized enclosed arcologies, orbital habitats, and biological adaptation.

AI-assisted summary of Colonizing Mars — original source. Check the original for full context.

Source published:

Key ideas

  • The intermediate phase of Martian colonization—between small research outposts and a fully terraformed planet—hinges on developing tradeable commodities and interplanetary economic interdependence rather than mere redundant living space. (0:00)
  • Martian space elevator logistics are anchored by Port Tharsis at areostationary orbit (17,000 km), using three carbon-nanotube tethers to Pavonis Mons, Olympus Mons, and Valles Marineris to balance dynamic orbital forces. (4:50)
  • Full planetary terraforming faces an extreme nitrogen bottleneck: replacing Earth's 5-billion-megaton atmosphere using 1-megaton tankers at one arrival daily would require 100 million years. (23:51)
  • Rather than a planetary monoculture, Mars is likely to develop into a multifaceted mosaic of paraterraformed 'worldhouse' domes, enclosed calderas with 10–20 km retaining walls, subsurface lava tubes, and orbital rotating habitats. (26:51)

Detailed notes

## Background Published on YouTube by futurist Isaac Arthur on August 17, 2017, this episode explores what it will realistically take to forge the Red Planet into a permanent home for humanity as the day of walking on Mars approaches.

## TL;DR Focusing on the often-overlooked middle ground between initial scientific outposts and centuries-distant terraforming, the episode examines how a developing Martian society might function and sustain itself economically. It traces an interplanetary transit network connecting cis-lunar staging hubs like Borman Station to a three-tether space elevator at Port Tharsis, branching down to settlements at Pavonis Mons, Olympus Mons, and Valles Marineris. Arthur contrasts competing colonial philosophies—ranging from localized paraterraforming and radical bioforming to orbital living and brute-force planetary terraforming—while illustrating massive logistical hurdles like nitrogen deficits and atmospheric erosion. Ultimately, the analysis concludes that the trajectory of Martian development should belong to the future generations living on the red dust rather than planners back on Earth.

## Atmosphere & style The presentation carries a pragmatic, contemplative tone that grounds grand speculative megaprojects in hard numbers, resource economics, and logistical realities. Arthur's signature calm, deliberate narration blends worldbuilding with dry realism, walking listeners through subterranean lava tubes, frontier bars, and dust-swept canyons with equal vividness. It feels less like an idealized space-age fantasy and more like an immersive tour of a functioning, somewhat weary frontier settlement grappling with harsh physics, political friction, and existential choices.

## Bulletin - [00:00](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=0s) The intermediate phase of Martian colonization—between small research outposts and a fully terraformed planet—hinges on developing tradeable commodities and interplanetary economic interdependence rather than mere redundant living space. - [04:50](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=290s) Martian space elevator logistics are anchored by Port Tharsis at areostationary orbit (17,000 km), using three carbon-nanotube tethers to Pavonis Mons, Olympus Mons, and Valles Marineris to balance dynamic orbital forces. - [23:51](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1431s) Full planetary terraforming faces an extreme nitrogen bottleneck: replacing Earth's 5-billion-megaton atmosphere using 1-megaton tankers at one arrival daily would require 100 million years. - [26:51](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1611s) Rather than a planetary monoculture, Mars is likely to develop into a multifaceted mosaic of paraterraformed 'worldhouse' domes, enclosed calderas with 10–20 km retaining walls, subsurface lava tubes, and orbital rotating habitats.

## Key takeaways - [00:00](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=0s) Permanent interplanetary colonies require distinct export commodities and economic integration with other worlds to avoid isolation and political collapse. - [02:36](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=156s) Staging Mars expeditions from lunar orbit (such as Borman Station spinning at 0.38g) lowers fuel escape requirements and standardizes crews to Martian gravity. - [02:36](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=156s) If human biology cannot permanently adapt to 38 percent Earth gravity, Mars will invert traditional coastal geography into orbital residence with temporary surface work shifts. - [04:50](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=290s) A stabilized three-tether elevator dropping from an areostationary altitude of 17,000 km bypasses rocket descents while balancing mechanical forces across non-equatorial settlements. - [09:07](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=547s) Light-speed communication delays of up to an hour necessitate on-site Martian legal, administrative, and political autonomy from Earth authorities. - [09:07](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=547s) Martian colonists rapidly fracture into regional rivalries and distinct demographics as civilian tradespeople, retirees, and tourists dilute initial scientific teams. - [11:04](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=664s) Early Mars settlements face an economic catch-22 because establishing export markets requires customer colonies elsewhere that do not yet exist. - [17:50](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1070s) Paraterraforming (the 'worldhouse' concept of doming canyons and craters) requires orders of magnitude less atmospheric gas and construction mass than open-air planetary terraforming. - [17:50](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1070s) Because Mars has lower gravity, producing Earth-like sea-level barometric pressure would create a much taller atmospheric scale height, enabling suitless breathing atop Olympus Mons. - [17:50](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1070s) An orbital-first faction argues for keeping Mars pristine for automated resource extraction and tourism while housing populations in rotating space stations. - [21:43](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1303s) Bioforming advocates propose modifying biology rather than planetary geology, ranging from moderate plant adaptation to radical cyborgs tailored to vacuum and radiation. - [23:51](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1431s) Terraforming risks catastrophic side effects: dumping liquid water onto unbound regolith would trigger global mud tsunamis and flash floods, while shielding atmospheres requires artificial orbital magnetospheres. - [23:51](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1431s) Volatile nitrogen is critically scarce in the inner solar system, making atmospheric mass transport from bodies like Titan or Venus a monumental logistical hurdle. - [26:51](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1611s) Mega-engineering containment walls 10 to 20 kilometers high could seal volcanic calderas into localized, highly pressurized biospheres that gradually vent air to the lowlands. - [32:44](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1964s) Ultimately, the development pathway of Mars will be chosen across centuries by permanent Martian residents whose cultural priorities may diverge entirely from replicating Earth.

## Detailed walkthrough ### [00:00](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=0s) Beyond the First Footsteps: The Neglected Middle Ground of Colonization

Life on Mars has captured human imagination for generations, fueling speculation about what living on the Red Planet might look like long before H.G. Wells published *The War of the Worlds*. Following the Upward Bound series—which focused on the logistics of getting into space faster, cheaper, and safer—the natural follow-up question becomes: once humanity is up there, what comes next? While the conventional answer is planetary colonization, typical discussions tend to get polarized at extreme ends of the timeline. Analysts either dwell endlessly on the initial voyage and tiny research bases of five to a hundred scientists, or leap straight across centuries to a fully terraformed world bustling with billions of inhabitants.

This exploration deliberately targets the intermediate phase that usually gets overlooked: a functioning, developing colonial society before massive terraforming has been completed. True terraforming and planetary engineering are reserved for an in-depth look during the subsequent colonization of Venus, while the extensive role of automated robotics is saved for an analysis of Titan. In linking these worlds, interplanetary trade emerges as the glue binding distant outposts together. A viable colony cannot exist purely as redundant living space; it requires distinct commodities to sell and import. While local self-sufficiency is vital for survival, commercial interdependence optimizes manufacturing output and prevents extraterrestrial outposts from abruptly fracturing along political fault lines.

Isaac Arthur emphasizes the essential economic foundation required for any permanent extraterrestrial presence, noting: “A colony, besides just serving as more living space for us, really needs to have some commodity it offers and others it needs.”

- **Conceptual Continuity:** Builds on foundational concepts from previous episodes, including *Industrializing the Moon*, *Asteroid Mining*, and the *Upward Bound* launch infrastructure series. - **Interplanetary Diplomacy:** Explores the classic science fiction trope of Earth-versus-Mars political fractures, analyzing how economic networks mitigate diplomatic divergence.

---

[02:36](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=156s) The Cis-Lunar Jumping-Off Point: Borman Station and Low-Gravity Transit

To bypass the repetitive mechanics of rocketry, the scenario opens with colonization already well underway. Orbital infrastructure is firmly established around Earth and the Moon, anchored by Gagarin Station in low Earth orbit, an active Earth orbital ring, and heavy lunar resource extraction centered at Armstrong Base. The true stepping stone into deep space is Borman Station, a rotating transit hub orbiting the Moon named after Apollo 8 commander Frank Borman. Borman Station rotates to simulate roughly 38 percent of Earth’s normal gravity—matching Martian surface gravity. This serves two crucial functions: acclimatizing travelers moving between Earth and Mars, and providing a long-term testing laboratory to determine how the human body, construction materials, and mechanical tolerances handle Martian gravity over multi-decade spans.

Staging the primary passenger pipeline from lunar orbit to Mars provides distinct logistical benefits. Escaping the Moon's shallow gravity well requires far less energy and fuel than lifting heavy expeditions directly from Earth's deep gravity well. Furthermore, proving full habitat viability and industrial extraction on the Moon provides a critical safety buffer relatively close to home before sending thousands of pioneers months away into deep space. Transit networks diverge sharply between passengers and freight: slow, ultra-efficient orbital transfer trajectories carry bulk industrial cargo over journeys lasting multiple years, whereas human crews travel aboard higher-energy passenger liners completing the trip in several weeks.

A critical biological assumption underpins the entire endeavor: that humanity can thrive indefinitely at 38 percent gravity with regular exercise and medical supplements, avoiding the need for continuous centrifuge living or radical cybernetic adaptation. As Isaac Arthur argues: “Should that turn out not to be true, I think Mars would be unlikely to ever become a genuine colony of Earth, or rather, you’d probably have a lot of rotating habitats around Mars that considered themselves Martian, but the planet itself would basically be a place folks spent time down on working there at mining facilities, not a home.”

```mermaid flowchart TD accTitle: Cis-Lunar to Mars Transit Network accDescr: Infrastructure flow showing how transit connects Earth, the Moon, and Mars orbital and surface hubs.

subgraph EarthMoon ["Cis-Lunar Infrastructure"] Gagarin["Gagarin Station & Orbital Ring<br>(Earth Orbit)"] Armstrong["Armstrong Base<br>(Lunar Resource Extraction)"] Borman["Borman Station<br>(Lunar Orbit, 0.38g Spin)"] Armstrong -->|"Raw materials & fuel"| Borman Gagarin -->|"Transiting personnel"| Borman end

subgraph Transit ["Transit Regimes"] Cargo["Bulk Cargo Shipping<br>(Low energy, multi-year duration)"] Passenger["High-Energy Liners<br>(Direct transit, several weeks)"] end

subgraph MarsSystem ["Martian System"] PortTharsis["Port Tharsis Hub<br>(Areostationary Orbit at 17,000 km)"] end

Borman --> Cargo Borman --> Passenger Cargo --> PortTharsis Passenger --> PortTharsis ```

- **Earth-to-Mars Transit Logistics:** Direct flights from Earth would need spin sections dialed down from 1.0g to 0.38g during transit; staging from Borman Station standardizes outbound crews to Martian conditions immediately. - **The Reverse Coastal Analogy:** If Mars gravity proves biologically insufficient for long-term health, Martian civilization would invert historical coastal geography: humans would reside permanently in orbit and commute down to planetary resource pits as hazardous temporary shifts. - **Economic Influx:** The maturation of carbon-nanotube synthesis makes space elevator tether fabrication economically feasible, opening Mars to regular passenger runs carrying several hundred travelers per flight.

---

[04:50](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=290s) Port Tharsis and the Three-Tether Elevator System

The incoming passenger ship does not perform an atmospheric landing; instead, it anchors directly in an areostationary orbit 17,000 kilometers above the Martian surface—a significantly lower orbital altitude than Earth's geostationary belt due to Mars's lower mass and rotational rate. Once parked directly over the Tharsis volcanic plateau, the ship itself is converted into the primary orbital terminal: Port Tharsis. Lower surface gravity makes tether construction far simpler on Mars than on Earth. While conventional materials suffice for lunar elevators, Martian elevators require high-tensile carbon nanotubes, which are manufactured on the Moon and ferried outward to Port Tharsis.

Rather than dangling a single tether down to an equatorial anchor point, engineers deploy a stabilized multi-tether guy-wire configuration. Isaac Arthur explains the structural strategy behind this planetary infrastructure: “So while a single space elevator just south of Pavonis is an option, we will instead be dropping three tethers down, then moving their ends to connect to the top of Olympus Mons, to Pavonis, and to Marineris canyon settlements.” By dropping three independent elevator lines to equatorial and non-equatorial sites in both northern and southern sectors, the orbital terminal remains dynamically balanced while providing redundant, non-rocket surface access to the planet's three core population centers.

```mermaid flowchart TD accTitle: Port Tharsis Three-Tether Elevator Architecture accDescr: Diagram illustrating the three-cable elevator system descending from Port Tharsis to three Martian surface settlements.

Station["Port Tharsis Station<br>(Areostationary Orbit - 17,000 km)"]

Station -->|"Tether 1 (Equatorial anchor)"| Pavonis["Pavonis Settlement<br>(Pavonis Mons / Capital)"] Station -->|"Tether 2 (Northwest anchor)"| Olympus["Olympus Settlement<br>(Olympus Mons Volcano)"] Station -->|"Tether 3 (Southeast anchor)"| Marineris["Marineris Settlement<br>(Valles Marineris Chasm)"] ```

- **Orbital Anchor Position:** Fixed at 17,000 kilometers over Pavonis Mons, a massive shield volcano standing significantly taller than Mount Everest near the Martian equator. - **Primary Settlements:** - *Pavonis Base:* The earliest surface habitat and historic planetary administrative center. - *Olympus Mons Outpost:* Located northwest of Tharsis atop the solar system's tallest volcano. - *Valles Marineris Base:* Built southeast of Tharsis inside the solar system’s largest canyon rift. - **Engineering Mechanics:** Non-equatorial anchors balance mechanical pull forces symmetrically across the center of mass, eliminating the orbital drift that would disrupt a single off-equator tether.

---

[09:07](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=547s) Emerging Society: UN Oversight, Local Rivalries, and Martian Law

The arrival of the three-cable elevator marks a turning point in Martian sociology and governance. Historically, the entire base fell under the authority of the United Nations Security Council, represented on-site by an appointed military commander stationed at Pavonis. Because electromagnetic communication between Earth and Mars experiences light-speed delays that can reach an hour for a single round-trip message, local autonomy was an operational reality from the start. Yet during the initial phase of a few hundred astronauts, political self-determination was an irrelevant concern: everyone was an intensively vetted, highly specialized scientist or engineer who relied entirely on mission support from home.

With the new influx of immigrants arriving down the elevator car at Pavonis, the character of the settlement is transformed. As the elevator doors open, the town is celebrating the grand opening of its very first civilian café. The demographic has broadened: these travelers are regular citizens, retirees, tradespeople, and tourists rather than hand-picked specialists. Reflecting on this cultural milestone, Isaac Arthur remarks: “This is no longer a mission where the best and brightest can be selected and screened for stability.”

Political friction has rapidly caught up to the growing population. The outposts at Olympus Mons and Valles Marineris increasingly resist bureaucratic dominance from Pavonis, demanding genuine democratic representation rather than UN decree. The legal system itself is forced to mature. The original magistrate spent years dealing exclusively with domestic probate, divorces, estate trusts, and wills resulting from relatives dying back on Earth—managing virtually no planetary felonies or misdemeanors. That idyllic period abruptly ends as humanity's primal nature reasserts itself on the frontier: a raucous barroom brawl erupts over political independence out at Olympus Mons, prompting the dispatch of a full-time resident magistrate to preside over the dispute.

- **Communication Lag Constraints:** Operational commands cannot be micromanaged from Earth because signal latency ranges up to an hour round-trip, requiring on-site executive power. - **Geopolitical Decentralization:** Olympus Mons and Valles Marineris actively resist the historical primacy of Pavonis, igniting inter-colony tensions over self-governance. - **Frontier Jurisprudence:** The transition from an elite academic research outpost to a multi-thousand-person frontier economy transforms the justice system from administrative contract filing to active law enforcement and dispute resolution.

[11:04](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=664s) Pavonis Mons and the Realities of Martian Colonization

As an outpost transitions into a permanent colony, its demographic and infrastructural profile must radically shift. While the initial base had a surplus of specialists in certain fields and a shortage of basic survival infrastructure, life at Pavonis Mons reveals an unexpectedly stark daily reality. A newcomer arriving at the settlement sees domes, but far fewer than anticipated for a population of several thousand. The surrounding landscape, though breathtaking, is desolate; the vast majority of the community actually resides underground in the caves and lava tubes carved into the giant shield volcano, with surface domes reserved strictly for hydroponics. The subterranean quarters can feel distinctly dreary, prompting colonists to ponder what truly justifies establishing a civilization on Mars. In the early days, pioneers arrived purely for the sake of the challenge—much like those who summit Mount Everest or winter in Antarctica, though almost no one chooses to establish permanent residency in those terrestrial extremes. In the near term, sheer numbers are not an issue: if even one-hundredth of one percent of Earth’s population chose to emigrate, that would supply one million settlers, and subsequent generations would steadily augment their ranks.

The underlying economic motivation, however, remains elusive. Historical models of terrestrial colonization offer few parallels: Mars will not serve as a penal colony like early Australia, nor are settlers fleeing religious persecution as in early North American settlements. Mars offers no high-value plantation cash crops like sugar or tobacco, and while the planet possesses vast reserves of iron, those are equally abundant on Earth and the Moon. Tourism provides some economic buffer—visitors drawn to the low gravity, colossal volcanoes, and labyrinthine canyons subsidize base operations, and a fraction decide to stay. Nevertheless, Isaac Arthur notes that the colony’s primary commercial engine is intangible: “Its major export right now is curiosity, prestige, and wonder, which keeps the money flowing from Earth, for now, but Earth doesn’t particularly need anything Mars has.”

At the local Pavonis Café, residents debating the future find themselves trapped in an interplanetary economic dilemma. Any goods Mars might profitably export rely on customers on other worlds, yet the only other inhabited body besides Earth and Mars is Venus, which hosts a solitary scientific outpost drifting in its upper atmosphere. Beyond that lie only scattered robotic probes across the outer solar system and nascent, experimental mining outposts in the asteroid belt. Martian trade is stalled in a classic catch-22, as settling Mars depends on trade with other colonies, which themselves cannot thrive without established trade partners. This dilemma spurs intense debate over the physical fate of the mountain: while some advocate eventual planetary terraforming, others argue against granting Mars open oceans and a free atmosphere, contending that the giant volcano should simply be hollowed out into an enormous self-contained arcology—effectively converting Pavonis Mons into a colossal planetary skyscraper.

[14:16](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=856s) The Trek to Valles Marineris and the Logistical Struggle

Traveling from Pavonis Mons to Valles Marineris could be done by riding the space elevator up to Port Tharsis and transferring back down, but making the journey via ground vehicle highlights the brutal logistical challenges of Martian transit. The razor-thin atmosphere prevents conventional aviation, yet that same lack of air resistance makes high-speed rail highly efficient. However, laying thousands of kilometers of track across Olympus Mons, Pavonis Mons, and Marineris remains a distant prospect. While Mars’s low gravity simplifies engineering by permitting steeper grades on crater slopes and cheaper bridges across chasms, the tiny workforce of a few thousand people is already consumed by basic survival tasks.

Every breath and bite on Mars demands intense industrial labor. Oxygen must be chemically cracked from water ice or baked out of regolith; nitrogen for agriculture is exceptionally scarce; and every hectare of crops requires either a structural dome or artificial lighting inside a lava tube. Furthermore, crops cannot be seeded directly into raw Martian regolith. Food production requires strict hydroponics or the labor-intensive synthesis of artificial soil created by churning raw dirt through giant vats of engineered microbes and algae. When the prospect of transforming Mars into a lush, Earth-like sphere comes up, the rover driver dismisses the concept outright: “It’s not worth doing, says the driver, going on about how at Marineris they’ve decided the future is in robust para-terraforming.”

The drive across the Martian wastes is protracted and constrained. Without an oxygenated atmosphere, internal combustion is impossible, forcing all vehicles to rely on electric battery banks. High-speed rail lines and regional power grids remain stalled because Earth refused to underwrite the massive expense of shipping heavy rail materials, and the local workforce is too small to manufacture them. Back at Pavonis, engineers dream of Earth exporting heavy fusion reactors; though massive and difficult to transport across interplanetary space, fusion power would eliminate the need for surface solar domes entirely, moving all food cultivation into dark, radiation-shielded cavern networks. Arriving at Valles Marineris underscores the incomprehensible scale of the Martian landscape: stretching 4,000 kilometers long, 7 kilometers deep, and over 200 kilometers wide at its greatest expanse, the rift defies any concept of bridging or enclosing it in a single span. Instead, settlement concentrates at Noctis Labyrinthus—the maze of narrower, shallower chasms filled with icy fog on the western fringe nearest Pavonis. Here, engineers are executing a pilot engineering trial: sealing off a canyon branch with massive retaining walls, enclosing it beneath a transparent roof, and melting regional ground ice to fill the very first artificial lake on Mars.

[17:50](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1070s) The Four Philosophical Camps of Mars

The engineering effort at Noctis Labyrinthus highlights the fracture of Martian society into distinct ideological factions regarding how the planet should be developed:

```mermaid flowchart TD accTitle: Four Philosophical Camps of Martian Colonization accDescr: Diagram showing the four viewpoints of Martian colonists: Paraterraforming, Full Terraforming, Pessimists, and Orbital Habitat Minimalists.

subgraph Surface["Surface-Focused Visions"] A["<b>Marineris: Paraterraforming</b><br/>• 'Worldhouse' concept<br/>• Segmented domes & laser defense<br/>• Low atmosphere volume needed"] B["<b>Olympus Mons: Full Terraforming</b><br/>• Global breathable atmosphere<br/>• Open-air living without suits<br/>• High atmospheric scale height"] end

subgraph Orbit["Alternative Visions"] C["<b>Pessimists: The Skeptics</b><br/>• Colonization was a mistake<br/>• Planets belong to robots<br/>• Plan to return to Earth"] D["<b>Orbitalists: Minimalist Footprint</b><br/>• Rotating habitats in orbit<br/>• Surface for automated mining only<br/>• Leave Mars pristine"] end

A <--> B C <--> D ```

The first camp, centered at Marineris, champions paraterraforming—often referred to as building a "Greenhouse Mars" or a "worldhouse." Recognizing the immense structural vulnerability of enclosing canyons, their engineers focus on hardening domes against micrometer impacts, abrasive dust storms, and structural failure. They envision defense networks utilizing radar grids and automated lasers to vaporize incoming meteors, tall peripheral curtain walls to shelter glazing from dust erosion, modular domes separated by airlocks, and graphene trusses paired with rapid-curing liquid spray sealants to patch punctures. Their primary argument rests on atmospheric physics: filling a dome only 100 meters high requires a trivial fraction of the gas needed to envelope an entire planet.

On Earth, standard atmospheric pressure is maintained by 14 pounds of air pressing down on every square inch (roughly 10,000 kilograms per square meter). Because Martian surface gravity is so much lower, generating identical barometric pressure without a roof requires an even larger mass of gas per unit area, pushing the atmosphere much higher into space. While terrestrial air thins out so dramatically that Mount Everest is nearly unbreathable and an Earth-bound Olympus Mons (at 22 kilometers high) would sit in less than one-tenth normal density, a fully terraformed Mars would feature a vastly taller atmosphere. Colonists would enjoy breathable air from the floor of the deepest chasms all the way to the peak of Olympus Mons.

This planetary transformation is precisely what the second faction champions: “That’s what the folks at Olympus Mons want, the second philosophical camp for Mars. They want to terraform the whole planet, so you can walk around anywhere without a spacesuit around you or a glass dome above you.” Though dismissed by the pragmatic engineers at Marineris as eccentric "blue sky dreamers," the Olympus Mons faction remains committed to a totally open, uncontained biosphere.

Returning to Pavonis Mons reveals the remaining two perspectives. The third camp is defined by pure pessimism: settlers who view the entire planetary enterprise as a disastrous miscalculation. Stranded temporarily and vocal in their discontent—particularly after the latest transport ship was repurposed to construct Port Tharsis rather than return them—they intend to board the next available vessel home. While still supportive of space exploration in the abstract, they argue that hostile planetary surfaces are suited solely for automated machinery, while human beings should confine themselves to terrestrial arcologies or comfortable orbital habitats. This aligns closely with the fourth camp, which advocates an orbital-first strategy. Leveraging the Port Tharsis space elevator, this group proposes that humans should reside primarily in rotating, Earth-like orbital stations where gravity, ecology, and radiation can be cleanly controlled. Down on the surface, human presence would be strictly limited to small oversight teams supervising automated mining operations, ice harvesting, and catering to high-paying tourists, leaving the pristine landscape of the Red Planet largely untouched.

[21:43](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1303s) Competing Visions at Olympus Mons

The planetary purists maintain that future tourists will have zero interest in traveling across the solar system just to look at artificial domes; visitors will come to experience the authentic Martian wilderness. Consequently, this faction advocates containing surface settlement to a handful of domed chasms, hollowed-out mountain caverns, or underground lava tubes, while keeping the bulk of the population and civil infrastructure up in orbit. They are not entirely hostile to terraforming Mars centuries in the future, but they believe the colony must first establish heavy orbital industries and lucrative exports to pay for the staggering quantities of nitrogen and water that would need to be imported from external sources like comets or outer planetary bodies.

```mermaid flowchart TD accTitle: Colonization Factions on Mars accDescr: Diverging philosophies for settling Mars ranging from planetary preservation to biological modification.

subgraph Surface["Surface vs. Orbit"] A["Orbital Industrialists / Purists<br/>Keep wilderness natural, build in orbit"] B["Classical Terraforming Camp<br/>Reshape planet to Earth standard"] end

subgraph Bioforming["Bioforming Alternatives"] C["Moderate Bioforming<br/>Native dirt, thin atmosphere, modified humans"] D["Extreme Bioforming & Cyborgs<br/>Post-biological entities tailored to vacuum"] end

A -.->|"Eventual import funding"| B B <-->|"Clashing philosophies"| Bioforming ```

Following the long and grueling trek across the Martian landscape to the peak of Olympus Mons—the tallest volcano in the solar system—the narrator reaches a settlement that has spread all the way up the mountain. Right at the summit sits a bar, the very establishment where a brawl broke out upon our initial arrival. Sitting down for a drink with our friend, the magistrate, reveals that Olympus Mons is not merely home to standard full-scale terraforming proponents, but is rather a battleground among three vehemently argumentative factions.

The first group insists on traditional full-scale planetary terraforming. The remaining factions dismiss this approach, advocating instead for bioforming the biology rather than the rock. This bioforming movement is itself split into two distinct sub-camps: - **Moderate Bioformers:** Proponents who favor engineering an intermediate ecosystem. They propose genetically engineering plants to process native Martian soil under a modestly thickened, nitrogen-poor atmosphere, while tweaking human biology to tolerate lower pressure and Martian gravity. - **Extreme Radical Bioformers:** Those who advocate engineering organisms suited for Mars entirely as-is, alongside cyborged humans who need no spacesuits, generate their own radiation shielding, and bypass biological respiration altogether. As this group puts it: “Why, they say, should we put all the effort into making this planet livable to humans and earth life, or even meet halfway in the middle, if we can just make new life that can live here?”

---

[23:51](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1431s) The Colossal Logistics of Terraforming

The magistrate confesses he has turned against full planetary terraforming due to the sheer engineering absurdity and unintended hazards involved. While Mars currently has virtually no atmosphere, global dust storms periodically induce a nuclear-winter scenario, completely blacking out the sun for weeks and crippling solar power collectors as well as surface farming. Introducing liquid water would tame these dust storms, but without deep root networks to bind the regolith, dumping oceans onto the surface would spark apocalyptic flash floods and continent-wide mud tsunamis. Furthermore, adding mass to alter Martian gravity is wildly impractical; dropping every asteroid from the asteroid belt and every moon orbiting Jupiter directly onto Mars would still fail to produce Earth-equivalent gravity, squandering unimaginable quantities of resources in the process.

```mermaid flowchart LR accTitle: The Nitrogen Import Bottleneck accDescr: Illustration of the logistical hurdle of moving Earth-scale atmospheres across the solar system.

subgraph Sources["Volatile Sources"] Titan["Titan"] Venus["Venus"] Sun["The Sun (Unusable)"] end

subgraph Logistics["Transit Bottleneck"] Fleet["1-Megaton Tankers<br/>Required: Thousands per day<br/>At 1/day: 100 Million Years"] end

subgraph MarsAtmosphere["Mars Target"] Shield["Artificial Magnetosphere Satellites"] Atmo["5 Billion Megaton Atmospheric Shield"] end

Sources --> Fleet Fleet --> Atmo Shield -.->|"Protects from solar wind stripping"| Atmo ```

The resource math becomes even more forbidding when analyzing atmospheric composition. Oxygen is abundant throughout the solar system bound in rock and ice, but volatile nitrogen is profoundly scarce. Beyond Earth, massive nitrogen reservoirs exist only on Venus, Titan, and inside the Sun itself—the last being physically inaccessible for atmospheric mining. The logistics of hauling mass across interplanetary space dwarf any normal shipping enterprise: - Earth's atmospheric envelope masses roughly 5 billion megatons, consisting predominantly of nitrogen gas. - A premier industrial transport vessel or orbital supertanker could carry about one megaton of cargo per trip. - Moving that inventory at a delivery cadence of one megaton per day would take an agonizing 100 million years, during which unshielded Martian atmospheric gas would steadily bleed away into the solar wind. - To complete delivery in any reasonable human timeframe, megaton-class bulk haulers would need to arrive thousands of times per day, or else operate at scales far exceeding any modern vessel. - Shielding the delivered gas requires deploying an orbital constellation of solar-powered satellite electromagnets to generate an artificial global magnetosphere, supplemented by vast orbital mirrors to heat the frigid, distant world.

As Isaac Arthur reminds the listener, terraforming does not merely tint the existing Martian geography green and blue; it fundamentally erases it: “It’s not the existing one just turning blue and green, all but the biggest landmarks are going to cease to exist as sea rises and land slides under torrential storms.”

---

[26:51](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1611s) The Colonization Spectrum and Radical Alternatives

Because total terraforming requires orders of magnitude more raw effort than any alternative, settling Mars will likely force colonists to evaluate competing development paths. Traditional terraforming is the brute-force route: altering day length, importing mass, moving orbits, or reshaping terrain. As Isaac Arthur emphasizes regarding this sheer overhead, “it requires orders of magnitude more effort to do that than some of our other options, it’s less finding a cave to live in then building an entire mountain on a plain so you can drill a cave into it.”

Bioforming presents an inverse dilemma regarding where to stop. Modifying human physiology to tolerate low pressures and thin atmospheres invariably leads down a slippery slope toward deeper genetic alterations, cyborgization, and eventual post-biological existence: - If humans are adapted to breathe near-vacuum air, engineering them to need no air at all becomes the obvious next step. - Transitioning to cyborg bodies removes biological vulnerabilities to radiation and nutrient shortages. - Once physical bodies and planetary atmospheres become obsolete, the physical planet is demoted to a mere quarry for raw materials. Humans could adopt digital mind uploads, dwelling within customizable, impossible virtual simulations while automated systems slowly dismantle Mars into rotating O'Neill-style habitats.

Rather than committing to an all-or-nothing planetary transformation, Martians could deploy localized hybrid alternatives:

```mermaid flowchart TD accTitle: Localized Terraforming Strategy accDescr: Concept for enclosing calderas with massive containment walls for localized terraforming.

Caldera["Olympus or Pavonis Mons Caldera Base"] Wall["10 to 20 km High Megastructure Wall<br/>'Great Walls of Mars'"] Atmosphere["High-Density Pressurized Air & Liquid Water"] Leakage["Controlled Atmospheric Leakage<br/>Slowly terraforms exterior lowlands"]

Caldera --> Wall Wall --> Atmosphere Atmosphere -.-> Leakage ```

- **Caldera Enclosures ("The Great Walls of Mars"):** Mega-engineering walls 10 to 20 kilometers high could be built directly atop the rims of calderas like Olympus Mons or Pavonis Mons. These enclosed basins could be pressurized with air and water immediately; any gas leaking over the rim would simply bleed down to feed the broader Martian plains. - **Partial Atmospheric Thickening:** Colonists could dome over chasms or build a low-pressure open-air atmosphere sufficient to burn up incoming meteors, allowing people to walk outdoors using simple breathing masks rather than pressurized spacesuits. - **Indigenous Microbes:** Uncovering native microbial life on Mars would present profound ethical questions regarding ecological contamination, but it would also yield extreme extremophiles uniquely adapted to marginal environments across the cosmos.

Looking forward toward the year 3000, the settlement of Mars will probably not conform to an ideological monoculture. Instead, it will feature a multifaceted mosaic: towering megastructure walls encircling terraformed calderas, self-sealing domed valleys, vast fusion-lit caverns carved into hollowed mountains, cyborgized colonists working the surface alongside biologically altered humans, and a massive orbital superstructure of rotating habitats whose electromagnetic deflector shields and meteor defense grids protect both the space settlements and the developing world below.

[32:44](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1964s) The Choice of Future Colonists

Ultimately, early Martian settlers will likely explore the entire spectrum of technological and living options before settling on what works best for them. Isaac Arthur reflects on a recurring principle in space colonization: present-day observers simply cannot determine the ideal path forward because humanity has never undertaken such an endeavor. More fundamentally, modern planners on Earth should not be dictating those choices in the first place. As Arthur emphasizes: “And as I often say when it comes to colonies, it’s not just that we nowadays don’t know for sure which options are best, what with having never done it, but it isn’t our decision anyway, it’s for the folks who live there to decide, and they have centuries to make that decision and they can change it down the road.”

Over generations, Martian society will evolve along its own trajectory. Centuries of living under lower gravity, beneath artificial domes, or inside subsurface lava tubes could alter their culture, psychology, and physiological priorities to such an extent that replicating Earth might no longer hold any appeal. As Arthur points out, “They may be so removed from us by then that they don’t want to be much like Earth.” The final destiny of Mars—whether it becomes a terraformed twin of Earth, a network of enclosed dome cities, or something entirely post-biological—belongs solely to the people who build their lives upon the red dust.

[33:11](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=1991s) Upcoming Episodes and Outro

Looking ahead to future topics, Arthur notes that the broader challenges and mechanics of terraforming planets to make them more Earth-like will be explored in depth during the upcoming episode on colonizing Venus the following month. In the immediate future, however, the channel turns back toward Earth to address the existential questions surrounding extraterrestrial life. Following up on the core notions of the Rare Earth hypothesis—which posits that Earth-like planets may be exceptionally uncommon in the universe—the next installment will examine whether intelligence itself, particularly human-level intelligence, is an exceedingly rare evolutionary outcome even on hospitable worlds. That upcoming release, titled "Rare Intelligence," serves as the concluding installment of the Fermi Paradox Great Filters series.

Arthur wraps up the episode by inviting viewers to subscribe and set notifications so they do not miss these forthcoming entries, encouraging those who enjoyed the deep dive into Mars to hit the like button and share the video with others. He signs off with his signature farewell: “Until next time, thanks for watching, and have a great week!”

- **Upcoming Schedule Mentioned:** - *Next Week:* "Rare Intelligence" (concluding the Fermi Paradox Great Filters series). - *Next Month:* "Colonizing Venus" (featuring an in-depth look at planetary terraforming).

## Notable quotes > [00:00](https://www.youtube.com/watch?v=kmFOBoy2MZ8&t=0s) A colony, besides just serving as more living space for us, really needs to have some commodity it offers and others it needs. — Isaac Arthur

## Mentioned H.G. Wells, Frank Borman, United Nations Security Council, Gagarin Station, Armstrong Base, Borman Station, Port Tharsis, Pavonis Mons, Olympus Mons, Valles Marineris, Noctis Labyrinthus, Mount Everest, Venus, Titan, Jupiter

## Video description The day comes ever closer when we will walk on Mars, but what will it take to forge the Red Planet it into a home for humanity?

Join this channel to get access to perks: https://www.youtube.com/channel/UCZFipeZtQM5CKUjx6grh54g/join Visit our Website: http://www.isaacarthur.net Join Nebula: https://go.nebula.tv/isaacarthur Support us on Patreon: https://www.patreon.com/IsaacArthur Support us on Subscribestar: https://www.subscribestar.com/isaac-arthur Facebook Group: https://www.facebook.com/groups/1583992725237264/ Reddit: https://www.reddit.com/r/IsaacArthur/ Twitter: https://twitter.com/Isaac_A_Arthur on Twitter and RT our future content. SFIA Discord Server: https://discord.gg/53GAShE Listen or Download the audio of this episode from Soundcloud: https://soundcloud.com/isaac-arthur-148927746/colonizing-mars Cover Art by Jakub Grygier: https://www.artstation.com/artist/jakub_grygier

Graphics Team: Edward Nardella Jarred Eagley Justin Dixon Katie Byrne Kris Holland of Mafic Stufios: www.maficstudios.com Misho Yordanov Murat Mamkegh Pierre Demet Sergio Botero Stefan Blandin

Script Editing: Andy Popescu Connor Hogan Edward Nardella Eustratius Graham Gregory Leal Jefferson Eagley Luca de Rosa Mark Warburton Michael Gusevsky Mitch Armstrong MolbOrg Naomi Kern Philip Baldock Sigmund Kopperud Steve Cardon Tiffany Penner

Music: Markus Junnikkala, "Hail the Victorious Dead" Dan McLeod, "Vacuum" AJ Prasad, "Staring Through" Markus Junnikkala, "A Memory of Earth"

[Source](https://www.youtube.com/watch?v=kmFOBoy2MZ8)

中文简报

地球化改造物流受阻，火星定居者转向封闭式穹顶 高昂的行星际运输成本与严重的氮资源匮乏，令完全的行星地球化改造变得不切实际，迫使火星文明依赖局域封闭式生态建筑、轨道栖息地和生物适应性改造。 本期节目聚焦于从最初的科学哨站到数百年后的地球化改造之间常被忽视的中间过渡阶段，探讨了一个正在发展的火星社会将如何运转并在经济上维持自身生存。节目梳理了连接地月空间中转枢纽（如博尔曼空间站）与位于塔尔西斯港的三缆太空电梯的行星际交通网络，该电梯向下延伸至孔雀山、奥林匹斯山和水手号峡谷的定居点。阿瑟对比了各种相互竞争的殖民理念——从局域副地球化改造和激进的生物构型改造，到轨道居住和强行行星地球化改造——同时展示了氮资源匮乏和大气侵蚀等巨大的物流瓶颈。分析最终得出结论：火星发展的轨迹应由生活在这片红色尘土上的后代决定，而非由地球上的规划者包办。 在火星殖民从小型科考前哨到完全地球化改造的过渡阶段，其成败取决于开发可交易商品以及构建行星际经济互依性，而不仅是提供冗余的生存空间。 (0:00) 火星太空电梯物流以位于火星静止轨道（17,000公里）的塔尔西斯港为核心，使用三条通往孔雀山、奥林匹斯山和水手号峡谷的碳纳米管缆绳来平衡动态轨道受力。 (4:50) 全面的行星地球化改造面临极端的氮资源瓶颈：若要以每天一艘百万吨级运输船的速度置换相当于地球50亿兆吨的大气，将需要1亿年的时间。 (23:51) 火星不太可能呈现单一的行星形态，而是可能发展为由副地球化改造的“世界之屋”穹顶、带有10至20公里挡壁的封闭火山口、地下熔岩管以及轨道旋转栖息地构成的多元马赛克格局。 (26:51)

Source quotes

[0:00] Isaac Arthur: A colony, besides just serving as more living space for us, really needs to have some commodity it offers and others it needs.

Original transcript

[0:00] Life on Mars has captured our imagination for many generations and we have wondered [0:05] what life would be like there even before H.G. Wells’ novel “The War of the Worlds”. [0:10] So, today we will tackle that topic. [0:35] We spent most of the Spring in the Upward Bound Series, looking at all the ways we might [0:39] be able to get into space faster, cheaper, and safer than now. [0:44] Once you get up there though the question becomes ‘what now?’. [0:47] Now the usual answer is that you can colonize planets, and of course that is our focus for [0:52] this series. [0:53] Yet, it often seems like discussions of this spend most of their time talking about how [0:57] to get there or some small colony of five or six people or maybe even a hundred or so. [1:03] Which isn’t much of colony honestly, or they jump all the way to terraforming the [1:07] planet with a population of millions or billions already. [1:10] I do want to spend some time on that phase of things, but the middle ground often gets [1:16] ignored. [1:17] So we’ll discuss true terraforming but save a more detailed look at that for next month’s [1:22] episode on Colonizing Venus. [1:24] Similarly, we often talk about the role of robots in space travel and colonization, and [1:30] it will likely play a big role in exploring and colonizing, but we’ll save a more detailed [1:35] look at that for Colonizing Titan, after Venus. [1:39] Connecting this episode to those two and others which may follow, we will look at concepts [1:44] like trade for networking these places to each other and Earth. [1:47] A colony, besides just serving as more living space for us, really needs to have some commodity [1:53] it offers and others it needs. [1:56] We always want any given colony to be as self-supporting as possible but at the same time, it does [2:01] help to have trade to both optimize production and help keep everyone welded together. [2:06] A common feature in discussions of extraterrestrial colonies is them breaking off, so you get [2:11] Earth versus Mars, and we’ll talk about that notion a bit today and throughout the [2:17] series. [2:18] Now you don’t have to have seen any of the episodes on this channel to watch this one, [2:22] but it is a bit of a sequel to the Upward Bound series and our previous discussions [2:26] of Industrializing the Moon and Asteroid Mining are essentially part of this series too, so [2:32] if you haven’t seen them yet, you may wish to watch them afterwards. [2:36] In any event, we are not interested in how to get to Mars, or what the ships that transport [2:41] people there are like, so we are going to jump to our colony already in progress. [2:47] One or more of the systems discussed in the Upward Bound series are in place and we’ve [2:51] got some orbital habitats around Earth and some serious resource extraction on the Moon. [2:56] In orbit around the Moon we have Borman station, named for the commander of the first manned [3:01] ship to orbit the moon back in 1968. [3:04] We’ll assume the main base down on the Moon is Armstrong Base and the main hub close to [3:09] Earth is Gagarin Station. [3:10] We’ll be spending a fair amount of time on Borman Station in the series as our jumping [3:15] off point to the solar system, so let me add that it is a rotating habitat simulating roughly [3:21] Martian gravity. [3:22] This was done for two reasons. [3:24] First, it gives folks going back and forth from Earth and the Moon a mid-point of gravity [3:29] to get used to the gravity at their destination; second, it lets us test the long term effects [3:34] of Martian Gravity on people, as well as construction and equipment tolerances for Mars. [3:40] A ship going straight from Earth or Gagarin Station to Mars might use a rotating section [3:46] that began at Earth gravity and spun down to Martian normal, during the trip, but we [3:51] will say most transit to Mars goes between Borman Station around the Moon to Mars. [3:57] Leaving from the Moon to Mars has some advantages, but the one we are mostly interested in is [4:01] that you can bring fuel and raw materials up from the Moon, and it’s lower gravity [4:06] well, rather than Earth. [4:08] Plus, starting a major base on the Moon let’s you prove it is viable before you start sending [4:14] people far further away from potential help. [4:17] Now we are going to assume we are not sending passenger ships to Mars at slow speeds, opting [4:22] for more energy intensive approaches, but for a large bulk cargo shipments around the [4:27] solar system you do probably want to use these most efficient approaches. [4:32] These can take years however, so it’s great for moving bulk material around but not people. [4:39] When our ship leaves Borman station, it will be carrying a few hundred new colonists on [4:43] a trip of several weeks to Mars, which already has 3 principal settlements on it of a few [4:48] thousand people each. [4:50] This ship is the first of many planned ones now that a space elevator has been planned [4:54] on Mars. [4:56] This ship will be carrying it, and indeed it is going to become the new space station [5:00] hub for Mars. [5:02] As we’ve discussed before, it’s easier to build elevators on lower gravity planets, [5:07] one on the Moon can be done with conventional materials for instance, Mars is harder but [5:13] a good deal easier than Earth. [5:15] We’ll leave it academic if anyone has managed to make an Elevator down to Earth and assume [5:19] they have an Orbital Ring instead, but we will assume someone has made one strong enough [5:24] for Mars and that it got manufactured down on the Moon. [5:28] As mentioned, part of Borman Station’s purpose was to test if people could handle Martian [5:33] Gravity in the long term, and it got started before the first Martian colonies did. [5:38] We don’t know if 38% of normal gravity is something people can tolerate in the long [5:43] term but for today we will assume the answer was yes, just with some supplementary medication [5:49] and exercise. [5:51] Should that turn out not to be true, I think Mars would be unlikely to ever become a genuine [5:56] colony of Earth, or rather, you’d probably have a lot of rotating habitats around Mars [6:01] that considered themselves Martian, but the planet itself would basically be a place folks [6:06] spent time down on working there at mining facilities, not a home. [6:11] Sort of a reverse of the concept of a classic coastal city, everybody lives on the land [6:16] and many go to work in the sea, often for protracted periods, only here lots of people [6:23] work on the planet but everyone lives in orbit. [6:27] So for the last few decades since men first stepped foot on Mars they’ve been testing [6:32] this notion and concluded that indeed, this gravity is sufficient and, unlike on the Moon, [6:38] they don’t need to use mixed spin and normal gravity for folks on the surface, something [6:42] we’ve discussed before, or cyborg people up. [6:46] Healthy exercise and some supplements are enough. [6:48] They’ve also got an orbital ring complete around Earth and a new production method for [6:53] carbon nanotubes to allow for a decently strong and cheap space elevator that can handle Martian [6:59] gravity. [7:00] With this in mind, the drive to colonize Mars has grown, and it is also economical to go [7:05] there for tourism, at least marginally economical. [7:09] Most people couldn’t afford it and most who can don’t want to, but at least many [7:13] thousands of folks can and do want to visit, so Borman station plans to start two-way trips [7:18] there leaving monthly with a couple hundred people each, many of whom will remain as colonists. [7:24] When this ship arrives though it is going to park in geostationary orbit, technically [7:29] areostationary orbit since it is Mars not Earth, but we will use geostationary in our [7:35] discussion of any orbit around any planet or moon that keeps hovering over the same [7:40] spot. [7:41] In our case, that will be 17,000 kilometers above Mars, closer than geostationary is for [7:47] Earth. [7:48] And they will hovering just over Pavonis Mons, a large mountain on Mars a good deal taller [7:53] than Mount Everest and quite close to the equator, in the Tharsis Region. [7:57] Humanity’s first Martian base was near there and is typically just called Pavonis. [8:02] We will name the ship turning space station Port Tharsis. [8:06] The other two settlements are close by, a ways northwest at Olympus Mons, the tallest [8:11] mountain in the solar system, and the other in Valles Marineris, to the southeast, one [8:16] of the largest and longest canyon systems in the solar system. [8:20] Now by default you want to have a space elevator right over the equator, and indeed we will [8:26] place Port Tharsis right over the Martian Equator, but as we discussed in the Space [8:30] Elevators Episode, you can connect multiple tethers to the same space station that connect [8:36] elsewhere than the equator, balancing out their forces, much like guy wires on a tower, [8:42] so long as at least one of those connects to the north and south hemispheres each. [8:47] So while a single space elevator just south of Pavonis is an option, we will instead be [8:51] dropping three tethers down, then moving their ends to connect to the top of Olympus Mons, [8:57] to Pavonis, and to Marineris canyon settlements. [9:01] So they have three, which provides plenty of redundancy and gives us direct access to [9:05] space and vice-versa. [9:07] This is handy because while Pavonis is the oldest and biggest settlement, a lot of folks [9:11] at Olympus and Marineris prefer to keep their settlements independent, and until recently [9:16] Pavonis was the nominal planetary capital. [9:19] There’s been quite a lot of arguing about that recently. [9:22] The original Mars colony was under the United Nations and since it can often take an hour [9:27] for a message to get to Earth and back with a reply, the security council has a commander [9:32] there who oversees things and is at Pavonis. [9:36] With all the new colonists arriving folks have been discussing something a little more [9:39] permanent and democrat and independent. [9:42] Back when it’s just a few hundred people this was fairly laughable; they needed to [9:46] phone home for everything and everyone was a specially trained and vetted expert at something. [9:52] This is changing. [9:53] As we step out of the first landing car arriving at Pavonis down that elevator, they are proudly [9:58] celebrating their first café being opened, and as we look around at our other fellow [10:03] travelers, we are reminded of their own backgrounds. [10:06] Having spent many weeks traveling with them, we know them well enough and most are not [10:10] experts. [10:12] This is no longer a mission where the best and brightest can be selected and screened [10:16] for stability. [10:17] One of our companions is the new magistrate who is supposed to be replacing the former [10:21] magistrate who dealt with minor misdemeanors but there were very few of those and never [10:27] any felonies, so he spent most of his time helping people with legal documents dealing [10:31] with issues back home. [10:32] Divorces, trusts, wills, etc. [10:35] In a colony of several thousand it is a rare day at least someone hasn’t had a family [10:39] member back on Earth die or had some sort of issue involving a relative. [10:44] Mars, the planet named for the God of War however, has just had its first big fight, [10:49] a barroom brawl off at Olympus over independence, and instead of replacing the magistrate, who [10:55] will be remaining in Pavonis, he is heading off to be the magistrate at Olympus. [11:00] The original colonists didn’t have a lot of folks with legal or law enforcements backgrounds [11:04] among them, there’s a lot of things they need to have, and at the same time they have [11:08] more than enough specialists from a lot of fields. [11:11] All of that is going to have to change as they transition from being an outpost to a [11:16] permanent colony. [11:18] But what about Pavonis? [11:19] What is this settlement like? [11:21] As a new colonist looking around, we do see domes and quite a few, but not as many as [11:26] we’d expect for a town of a few thousand. [11:28] But beyond those the view, while breathtaking, is quite barren. [11:33] Most of the settlement is in caves and lavatubes in and around the giant mountain. [11:38] Those domes are just for hydroponics. [11:40] Going inside, it seems a bit dreary even, and we find ourselves wondering what the appeal [11:45] is to come to Mars. [11:47] Oh sure, the first few thousand folks who came here did so for the simple motivation [11:51] of coming here. [11:53] People go to Mount Everest or Antarctica just to go there, but precious few decide to live [11:58] there. [11:59] In the short term that’s not too big a problem, even if only 1% of 1% of Earth’s population [12:05] wanted to come to Mars that would still be a million people, far more than the current [12:10] population, and of course once there they’ll have children themselves and doubtless there [12:14] will always be more people wanting to come to. [12:17] And yet, what is the appeal? [12:19] What drove colonization on Earth? [12:21] It’s very unlikely many folks would be sent to Mars as prisoners, as with Australia, or [12:27] to flee religious persecution as was the case with many American colonies. [12:31] There’s no luxury crops like sugar or tobacco to grow in plantations on Mars. [12:36] Mars has plenty of iron, but so does Earth and the Moon. [12:40] It is a breathtaking place to vacation, low gravity with mountains that dwarf anything [12:45] on Earth and vast canyon systems too, and that’s something since some folks might [12:50] visit, subsidizing the colony, and decide to stay too. [12:55] Its major export right now is curiosity, prestige, and wonder, which keeps the money flowing [13:00] from Earth, for now, but Earth doesn’t particularly need anything Mars has. [13:06] Folks sitting around the new Pavonis Café discussing the future of Mars try to think [13:10] of stuff, but they mostly can only see things Mars can import or export to other planets, [13:16] and right now the only other planet besides Mars and Earth with any people on it is Venus [13:21] which has a small scientific outpost floating in its atmosphere. [13:26] There are also a few experimental mining operations in the asteroid belt and various robot probes [13:31] poking around the planets and moons of the outer solar system. [13:34] Trade, they think, has to wait on the rest of the solar system getting settled, and they [13:40] worry there might be a catch-22 in there, since the motivation to settle all the places [13:44] seems to revolve around other places already being settled too. [13:49] Of course they talk about terraforming Mars one day too, not just living inside mountains [13:53] and lava tubes and domes, and some say that it isn’t even something far ahead in time, [13:58] but never, that there is no advantage or purpose to trying to give Mars its own atmosphere [14:03] and oceans. [14:04] That they should keep on just making new domes with air inside them and basically turn the [14:09] giant mountain they live in into one big arcology, essentially a giant mountain hollowed out [14:14] into a skyscraper. [14:16] The folks over at Marineris feel a bit differently though, and that’s where we are bound. [14:21] We could, of course, take the elevator back up to Port Tharsis and back down to Marineris, [14:26] but instead we will be taking a ground vehicle. [14:29] The lack of any serious atmosphere makes flight on Mars very difficult, but it also means [14:34] high-speed rail is cheaper since there’s not much air drag to fight. [14:38] That’s going to be a while because while it would be very handy, building a few thousand [14:43] kilometers of track between Olympus, Pavonis, and Marineris won’t be easy. [14:48] In some ways it is easier than on Earth, low gravity makes bridges over chasms cheaper, [14:53] and you can get away with much sharper inclines up and down craters and hills, but you’ve [14:58] only got a population of thousands, not millions, and you have to use a lot larger percentage [15:03] of your population for just basic food and life support here too. [15:08] Oxygen is plentiful enough, but it all has to be liberated from water or baked out of [15:13] rock. [15:14] Nitrogen for plants is hard to find, and every acre or hectare of crops you want to grow [15:19] needs a dome over it first, or artificial lighting if done underground in a lavatube [15:24] or cave. [15:25] You can’t plant your crops in raw Martian dirt either, it has to be done hydroponically [15:30] or in soil made by taking that dirt and processing it in huge vats full of microbes and algae [15:36] first. [15:37] The notion of transforming Mars into an Earth-like planet is daunting to say the least. [15:38] It’s not worth doing, says the driver, going on about how at Marineris they’ve decided [15:42] the future is in robust para-terraforming. [15:45] That’s where you just slowly cover an entire planet over in domes, to keep the air in and [15:52] the local soil out. [15:53] Glass above, concrete below, and you just add dirt you’ve made into them. [15:59] They plan to eventually dome over the entire Valles Marineris cavern system. [16:03] The drive there is slow going, part of why they want that rail system, because there’s [16:07] no gas station on Mars and no air for them to use to burn that gas anyway. [16:13] Everything is electric and battery operated. [16:15] They don’t really have the manpower for building rail or power lines yet and Earth [16:20] said no to shipping those in. [16:22] What they’re really hoping for back at Pavonis though is one of those new fusion reactors [16:26] from back on Earth. [16:28] They’re big, heavy, and getting one to Mars would be a problem; but once here, they don’t [16:33] need above ground domes anymore. [16:35] They could do all their growing in vast lavatubes and caverns that wouldn’t need sunlight [16:40] then. [16:41] Valles Marineris is stunning in scope. [16:43] It’s not that it is 4000 kilometers long, it’s that it is 7 kilometers deep and at [16:49] its widest, over 200 kilometers. [16:52] It’s almost incomprehensible, even in low gravity, to imagine a single bridge spanning [16:58] that, let alone a dome. [17:00] Fortunately our real destination is Noctis Labyrinthus, a series of maze-like smaller [17:06] chasms on the western edge of Valles Marineris closest to Pavonis Mons. [17:11] It begins just a few hundred kilometers southeast of Pavonis and its many smaller, narrower [17:16] chasms are filled with an icy fog. [17:19] This pilot project for terraforming has selected one of the narrower, shorter, and shallower [17:24] canyons, and they are busy walling up the end so they can dome the whole thing over [17:28] and pump in water from the ice in the area to make the first lake on Mars. [17:33] It’s stunning to take in the scope of this dome, just a few kilometers long and wide, [17:38] and you are already wondering about cracks or meteor strikes on it and how they plan [17:42] to deal with them, let alone how they plan to build titanic ones across the wider parts [17:47] of the main Valles Marineris chasms. [17:50] As we settle in we start seeing four distinct viewpoints among the colonists. [17:55] Here in Marineris, the interest is all in domes: endless domes to eventually cover the [18:00] whole planet. [18:01] And the focus is on how to manufacture them and repair them and harden them against cracks [18:06] and meteor strikes. [18:08] Grids of radar and lasers to shoot down incoming meteors, possibly tall curtain walls around [18:13] the edges to help minimize erosion damage to the domes from dust storms. [18:18] Individual smaller domes connected with airlocks or great big ones with graphene supports and [18:22] liquid patches that could be rapidly sprayed on any crack or hole. [18:27] They envision not so much a Green Mars as a Greenhouse Mars: a ‘worldhouse’ as it [18:32] is sometimes called. [18:34] They point out that it is far easier to get all the nitrogen and oxygen they need for [18:38] atmosphere, when it is only maybe a hundred meters high, not kilometers. [18:43] If you want to have normal air pressure just from gravity alone, with no ceiling or walls, [18:49] you need to have a lot of air piled on top of air. [18:51] On Earth, every square inch of surface has 14 pounds of air over it, stretching many [18:58] miles, or 10,000 kilograms per square meter. [19:02] On Mars, because of the lower gravity, you actually need more air per unit of area, to [19:07] have normal air pressure. [19:08] That means your atmosphere has to go up higher. [19:11] On Earth, at the top of Mount Everest, it’s fairly hard to breathe as the air has thinned [19:17] out a lot by that height, and the pressure dropped. [19:21] If we could transport Olympus Mons back to Earth, at 22 kilometers in height, the air [19:26] density wouldn’t even be a tenth of what we are used to. [19:29] Conveniently on Mars, since the atmosphere would have to stretch up higher, you might [19:34] still be able to breath all the way at the peak of Olympus Mons, and still be able to [19:38] down at the bottom of those chasms, where pressure would keep rising, though odds are [19:44] they’d all be full of water anyway. [19:46] That’s what the folks at Olympus Mons want, the second philosophical camp for Mars. [19:52] They want to terraform the whole planet, so you can walk around anywhere without a spacesuit [19:56] around you or a glass dome above you. [19:59] We’re curious about them, though the folks at Marineris say they’re all blue sky dreamers [20:04] and more than a bit batty, but we decide to visit them anyway. [20:08] To do so we first have to go back to Pavonis, and meet with folks from the other two camps. [20:14] One of them is simply the pessimism camp. [20:16] They think this whole idea was a mistake and they shouldn’t have come here at all. [20:20] They are going home when the next colony ship arrives, there’s always plenty of space [20:24] on those for a return trip, and they’re irritated the most recent ship became Port [20:29] Tharsis instead. [20:30] They’re basically loitering around Pavonis sowing pessimism. [20:34] They’re still pro-space expansion, they did come here in the first place after all, [20:39] but they’re thinking planets and moons besides Earth are for robots to live on, and people [20:44] should stick to arcologies on Earth or perhaps rotating habitats in orbit. [20:48] That’s our fourth camp too basically. [20:51] They like the idea of having settlements down here on Mars but they think, now that there’s [20:56] easy access back to orbit with the elevators up to Port Tharsis, that they can have just [21:00] a few settlements planetside but do most of their living up in orbital habitats, like [21:05] all the ones being built around Earth these days, and settlements here should be mostly [21:09] about comfort for the folks who need to be down here overseeing mining. [21:14] Yes robots would be handy but they still need a lot of oversight and a lot of times it’s [21:18] just easier to use a person. [21:20] But they want nice, contained, truly Earth-like habitats and they figure all their other industry [21:26] and agriculture can be done on those in orbit. [21:29] There’s no need to dome over the whole planet, let alone terraform it. [21:33] Just a few places here and there for mineral extraction, ice mining, and for the tourists [21:38] to visit of course. [21:39] Indeed, better to leave the planet mostly as-is. [21:43] They figure no tourist is going to want to visit domes; they want to see the natural [21:47] terrain. [21:48] They’re all for a few of these projects, doming over a few chasms, having a few lavatube [21:53] habitats underground or in the mountain caverns, but they’d rather see Martian settlement [21:59] mostly happen in orbit. [22:01] They are somewhat open to the notion of terraforming Mars centuries down the road, but the way [22:06] they see it, they first need to get their industries built up and have exports. [22:11] This way, they can eventually pay for the huge amounts of nitrogen, and probably water [22:15] too, they’d need to bring in from other planets or comets. [22:20] So we set out on the much longer trek to Olympus Mons, and the last stretch is rather grueling [22:26] because they have set themselves up all over the mountain including the peak, and we do [22:30] want to see Mars from the peak of the tallest mountain in the solar system. [22:34] It is no surprise that there is a bar up there and it is the one the fight broke out at earlier [22:40] when we first arrived. [22:42] We run into our friend, the magistrate there, and share a drink. [22:45] He informs us that this is not the home of the second philosophical camp, the folks that [22:50] want to terraform Mars completely, but rather three camps who argue with each other a lot. [22:56] One group does want to terraform Mars, while the other group wants to bioform people and [23:01] plants on Mars. [23:03] And indeed, that’s split into two subgroups as well. [23:07] One wants to set up an ecology where everything can live on native Mars dirt and not as thick [23:12] an atmosphere, less nitrogen than Earth too, but thicker than now. [23:16] Plants genetically engineered to use the native soil. [23:19] People engineered to live on thinner air and better adapted to the local gravity. [23:25] The other group wants to go completely native: organisms tailored from the ground up to live [23:30] on Mars as-is; people cyborged up to walk around without spacesuits, who don’t need [23:36] to breathe and are safe from radiation concerns too. [23:40] Why, they say, should we put all the effort into making this planet livable to humans [23:45] and earth life, or even meet halfway in the middle, if we can just make new life that [23:49] can live here? [23:51] The magistrate seems to have been converted. [23:53] There’s so many problems with terraforming he says. [23:56] The planet has virtually no air but when the duststorms come they are like a nuclear winter, [24:01] blackening the sky for days or even weeks at a time, so solar power can be unreliable [24:07] and plants need supplemental lighting. [24:09] If you get oceans and moisture in there, that would stop; but suddenly exposing the planet [24:15] to lots of water is likely to result in huge flash floods and tsunamis of mud, with no [24:20] plants and roots to hold them down. [24:23] It will never have enough gravity to be like Earth, even if we dropped every asteroid in [24:28] the belt and every moon around Jupiter on Mars, we still wouldn’t increase the gravity [24:32] that much, and it would be kind of wasteful. [24:35] But even ignoring the gravity, we’d need to bring in air from elsewhere. [24:39] Sure there’s enough oxygen, oxygen is plentiful pretty much everywhere in the solar system. [24:44] But not nitrogen. [24:46] The only abundant supplies for that besides Earth are Venus, Titan, and of course the [24:50] Sun itself. [24:52] But good luck lifting that nitrogen off of a star. [24:55] He points out that it isn’t like moving a few colonists; we’re talking about moving [24:59] atmospheres and those are pretty heavy. [25:02] Earth’s atmosphere is 5 billion megatons, mostly nitrogen, and when we think of big [25:09] ships, even huge oil tankers, a single megaton is about as much cargo as they could carry. [25:15] If one arrived carrying a megaton of nitrogen every day, it would take 100 million years [25:21] to bring in enough nitrogen, and without a magnetosphere on Mars, it would probably evaporate [25:26] away before we finished. [25:28] No one wants to wait a hundred million years, so that means you’ve got megaton tanker [25:32] ships arriving not every day but at least thousands of times a day, or ships far larger. [25:39] And until near the end, there’s not much use to that existing atmosphere, part way [25:43] through you can start adding water and possibly some tailored plants to get some basic ecological [25:49] cycles going. [25:50] During that whole time, inhabiting the planet still means living inside domes or caverns [25:55] and you’d have to worry about those being destroyed in the geological chaos of a planet [26:00] gaining oceans and atmosphere. [26:03] To keep that atmosphere there, we’ll also need to ring the planet in satellites, sucking [26:07] in solar power to run electromagnets and create an artificial magnetosphere. [26:12] Mars is cold and far from the sun too, so you probably need to be considering orbital [26:17] mirrors to bring in some more light. [26:19] Those are both fairly hard tasks, though both are dwarfed by the task of bringing in all [26:24] that nitrogen and probably water too. [26:28] This is not a terraforming episode, we did one of those before and will look at such [26:32] concepts again in the next episode on Venus, but it is always good to remember that terraforming [26:38] a planet fundamentally alters it. [26:40] It’s not the existing one just turning blue and green, all but the biggest landmarks are [26:45] going to cease to exist as sea rises and land slides under torrential storms. [26:51] No, this episode is about colonizing Mars and we see a handful of paths for doing that. [26:58] There’s the terraforming route, make the place as much like Earth as you can, and as [27:03] we discussed in that terraforming episode you have tons of options depending on how [27:07] far you are willing to go, up to and include adding mass to a planet or changing its day [27:13] length or even moving the thing to be closer or further from a star. [27:17] If you’ve got the will to do it, and the resources, you can terraform Mars to whatever [27:23] degree you see fit. [27:25] But it requires orders of magnitude more effort to do that than some of our other options, [27:30] it’s less finding a cave to live in then building an entire mountain on a plain so [27:35] you can drill a cave into it. [27:38] Possible but probably not ideal. [27:41] Bioforming is an option, but again it comes down to how far you are willing to go, just [27:46] in a different direction. [27:47] You might be able to limit yourself to fairly minimal tweaks to plants, animals, and people, [27:53] and meet halfway in-between, terraforming part way too, but once you open the door to [27:58] that path, there is the question as to why not walk down it further? [28:02] And how far is too far? [28:04] And since the path for meeting in the middle still takes many centuries at least, isn’t [28:09] that likely to end up as a sliding standard as people move the milestones on what is acceptable? [28:15] If you are modifying people to the point that they can breathe easily in very thin air, [28:20] why not in no air? [28:22] And why not just go the full cyborg route and not need food or air? [28:26] In that context why do you even need planets, except maybe for raw materials, and maybe [28:32] why even a body at all, in favor of a digital existence in a virtual landscape of your choosing, [28:38] on any planet including surreal landscapes which are not physically possible? [28:43] And that is an option too. [28:45] So is the option of making Martian mean folks who live around Mars, and some who just go [28:50] down to work the mines or visit the place. [28:53] The slow disassembly of the planet to construct rotating habitats, built as needed. [28:58] I don’t know which is best, I guess that will be for the Martians themselves to decide [29:03] down the road. [29:05] If I had to guess though I would wager on a little of all of the above. [29:09] There’s a mistake in thinking for instance that you actually have to terraform an entire [29:13] planet or not at all. [29:15] As an example, the mountains, Pavonis and Olympus Mons, sit in the middle of volcanic [29:21] caldera, and when you think of things like caldera or craters you often think of a bit [29:25] of bowl with a rim around it. [29:27] There’s nothing stopping you from extending that straight up, like the Great Wall of China [29:32] encircling a place only 10 or 20 kilometers high. [29:36] That sounds like an insane project, but it really is no different then doming over such [29:41] an area or manufacturing a rotating habitat. [29:44] You could then fill just that area with air and water, some would leak out, but just to [29:49] the rest of the planet, so you could build one that was decently small to begin with, [29:54] fill it with air and water, and just keep adding more to it, localized terraforming [29:58] that also slowly terraforms other areas if you want. [30:02] A similar concept is building up your atmosphere by doming over areas and just filling them [30:08] with new air and not worrying about what gets lost to leakage. [30:12] You don’t necessarily need a full Earth Atmosphere on the planet either. [30:17] People can survive for short periods in much lower pressure than Earth’s, and some organisms [30:22] might do just fine in it even without modification, and it doesn’t take too much air to give [30:27] you a shield against most meteors. [30:30] People might get used to wearing masks when they go all the way outside, which might not [30:34] be too common if they just need to repair leaks. [30:38] Indeed since those various crack and spots near the leaks will be in between the local [30:42] native environment and the artificial one, it’s not a bad place to experiment with [30:46] limited bioforming, the methods where you meet halfway in the middle. [30:50] Heck, there is even a chance we might find some simple life on Mars, unlikely but we [30:56] can’t rule it out yet. [30:58] That of course raises the issue of whether or not it is okay to colonize a planet that [31:02] already has life on it, and if so, do simple microbes count? [31:08] But also, if we did find life there, it might be very valuable. [31:12] Odds are there are a lot more marginal planets like Mars out there in the galaxy than Earth, [31:18] and being able to use those, or some modified version of them, to help in early terraforming [31:24] might make them very valuable indeed. [31:26] I don’t know what the future of Mars holds, but if I had to guess, if we checked back [31:31] on our colony in the year 3000, I would expect a little of everything. [31:36] Yes some Great Walls of Mars encircling some place that was genuinely terraformed. [31:41] Yes giant domes over chasms, with protection from meteors and self-sealing capabilities. [31:47] Yes smaller domes, yes big underground cities or hollow mountains artificially lit by fusion [31:53] power. [31:54] Yes some people who have modified themselves to live in the natural Martian environment, [31:59] or to meet it halfway in between. [32:01] And yes, a swarm of rotating habitats above, where people live and grow food and manufacture [32:07] materials for export and handle imports of giant ships carrying water and air. [32:13] Each one generating a magnetic field for its own protection and to act in concert as a [32:18] shield for the planet below. [32:21] Indeed each with its own defense grid to shoot down meteors that might hit them or the planet, [32:26] and orbital mirrors that bring in more light. [32:28] They might eventually have to choose to terraform all the way or not, to bioform or not, or [32:35] even to disassemble the planet for materials or not. [32:38] But for a very long time they could choose not to occupy somewhere in the middle but [32:44] the whole spectrum of options, if and until they decide which is best. [32:49] And as I often say when it comes to colonies, it’s not just that we nowadays don’t know [32:54] for sure which options are best, what with having never done it, but it isn’t our decision [32:59] anyway, it’s for the folks who live there to decide, and they have centuries to make [33:04] that decision and they can change it down the road. [33:07] They may be so removed from us by then that they don’t want to be much like Earth. [33:11] We’ll discuss making planets more Earth-like by terraforming more in our episode on Colonizing [33:16] Venus next month, but next week we will be returning to Earth and following up on the [33:22] Rare Earth Hypothesis notions that Earth-like planets are incredibly rare by asking if intelligence, [33:28] especially human level intelligence, might be quite uncommon to develop even on Earth-like [33:34] planets, in our close out episode of the Fermi Paradox Great Filters series, Rare Intelligence. [33:40] For alerts when those and other episodes come out, make sure to subscribe to the channel. [33:45] If you enjoyed this episode, hit the like button, share it with others. [33:50] Until next time, thanks for watching, and have a great week!