Instigator / Pro

MOON vs. MARS: Which destination should humanity colonize first? PRO=MOON CON=MARS


The debate is finished. The distribution of the voting points and the winner are presented below.

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After 1 vote and with 5 points ahead, the winner is...

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Two days
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One week
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Contender / Con

PRO=MOON colony first
CON=MARS colony first

BURDEN of PROOF is shared- both sides must make an affirmative case for their preferred project. In effect, we have two policy resolutions:

RESOLVED:Humans should colonize the Moon first
RESOLVED:Humans should colonize Mars first

NO KRITIKS, please, for this debate: both sides should assume that human space colonization is both achievable and desirable over the next few centuries of human history. Political questions regarding the governance of any hypothetical colony ought not to be considered for this short debate.


THE MOON is an astronomical body that orbits the planet Earth and acts as its only permanent natural satellite.

MARS is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury.

HUMANS (Homo sapiens) are the only extant members of the subtribe Hominina. A terrestrial animal, humans are characterized by their erect posture and bipedal locomotion; high manual dexterity and heavy tool use compared to other animals; open-ended and complex language use compared to other animal communications; larger, more complex brains than other animals; and highly advanced and organized societies.

COLONIZATION requires the establishment of permanent habitats that have potential for self-expansion and self-sustenance.

- RULES --
1. Forfeit=auto loss
2. Sources may be merely linked in debate as long as citations are listed in comments
3. No new args in R3
4. For all relevant terms, individuals should use commonplace understandings that fit within the rational context of this resolution and debate

Round 1
Thanks, RM for accepting this debate.

PRO argues that humans should colonize the Moon first, before colonizing Mars.

I. Proximity

The nearness of the Moon is its most compelling and favorable argument, profoundly influencing every other consideration.  At perigee, the Moon is only 362,600 km distant, a mere 3 days travel for modern rockets.  The closest distance between Mars and the Earth is about 54 million km or 150 times more distant. lose approaches are far rarer and more fleeting than lunar near approaches- roughly once every 780 days.  Using lowest energy consumption windows,  we need about 9 months to fly to Mars and that window of lowest consumption only comes around every 26 months.

I.A. Health and Safety: Space is the most hazardous environment ever explored by humans.   Astronauts face
  • confinement to small spaces,
  • long periods of isolation, boredom,
  • high stress,
  • space sickness, disorientation,
  • micro-gravity decreases bone density, atrophies muscles, impairs vision,
  • radiation exposure increases cancer risks, damages cognitive abilities.  Astronauts caught outside of Earth's magnetic field during a significant geomagnetic storm could suffer lethal exposure.
Although voyagers Moon and Martian voyagers face similar perils terms of space flight, the shortest trip to Mars takes roughly 90 times as long as a trip to the Moon, increasing all of these hazards many fold.  Moon first allows colonists to limit exposure to these hazards relative to Mars while also developing the protocols and adaptations best suited for future missions.

I.B. Evacuation and Rescue:  Relatedly, in the event of disaster, escape from the Moon's low gravity to the safety of Earth should be relatively easy to plan for and execute.  We'd have the option of having a rescue ship standing by to provide emergency aid and support within 3 days.  Similar evacuation or rescue plans for a Martian colony are only realistic during the few weeks of near approach.  We should note that the success or failure a first colony has the potential for major impacts on support and funding for future missions.  One decisive consideration for our first space colony should be limiting risk wherever possible.

I.C. Temporary and replacement populations:  An initial space colony that's only 3 days travel time from Earth can accommodate temporary populations.  For example, we could send a larger initial group for construction and set-up then fly some workers home after the settlement is up and running.  We could realistically consider accommodating tourists and other non-essential personnel for commercial and promotional benefit.  All of these options are exponentially more difficult to support for a Martian colony.
I.D Communication:  Likewise, communication between Earth and any lunar colony would be continuous and almost instantaneous.  Colonists would be able to receive updates, transmit data, talk to relatives, upload entertainment, etc in real time.  Martian communication delays run from 3 minute minimum to a 22 minute maximum.  Moreover, every other year there will be a 2-3 week period of solar conjunction, when Mars will be behind the Sun and communication will be difficult to impossible.

I.E. Resources:  Beyond tourism potential, the Moon is rich in metals:

"Elements known to be present on the lunar surface include, among others, are hydrogen, oxygen, silicon, iron, magnesium, calcium, aluminium, manganese, and titanium. Among the more abundant are oxygen, iron and silicon. The atomic oxygen content in the regolith is estimated at 45% by weight.
Solar power is far more available without the atmosphere or unpredictable weather of Earth (or Mars) to overcome.  Both polar regions are illuminated almost constantly.  Although scientists have confirmed that lunar water exists, quantity and ease of extraction are still unconfirmed.

I.F.  Transportion Costs:  Any space exploration is going to be expensive.  Although reliable cost estimates are hard to verify and the technological innovation consistently shrinks those estimates over time, we can say with confidence that any Moon colony would be far cheaper than Mars.  For the sake of rough comparison, let's note that NASA's Artemis program has proposed 24 unmanned and 8 manned missions to the Moon's southern polar region over the next 8 years at an estimated cost of $20 to $30 billion while the cost of the  first manned mission to Mars is currently estimated at about $500 billion.  Obviously, any self-sustaining human settlement would multiply both mission cost figures tremendously but these figures are offered here to provide a rough sense of proportion.
  • One major additional cost savings is found in the relatively inexpensive cost of launching from the Moon's weak gravity- small packages can be practically catapulted back to Earth.
II.  Spaceport:  If humans intend to explore or exploit the Solar System, a sustainable spaceport where vehicles can be constructed or assembled, stored, maintained, re-fitted and re-fueled will eventually become irresistibly cost effective, as well as reducing the near-orbit space debris problem around Earth. Weak gravity makes the Moon a good location for a spaceport or even supporting a spaceport in lunar orbit.  Most investment along these lines has the advantage of offering substantial savings to future Mars missions as well as any and all other space objectives.

III. Weather:  Lunar weather  is highly stable and predictable compared to Mars.
  • A Lunar day is 29 and 1/2 Earth days- so every night is about 354 hours long.  This creates some challenges for solar power and agriculture and requires planning for major temperature extremes but the advantage of the Moon is that this cycle is very predictable.  Winds, dust storms, and precipitation don't present as obstacles on the Moon as opposed to any planetary destination.
  • A colony built near the Moon's poles could exploit continuous or near-continuous illumination as well as the likelihood of exploitable water supplies in the permanently shadowed craters of the poles.
IV. Planning and funding already underway:

"On 11 December 2017, President Trump signed Space Policy Directive 1, a change in national space policy that provides for a U.S.-led, integrated program with private sector partners for a human return to the Moon, followed by missions to Mars and beyond. The policy calls for the NASA administrator to "lead an innovative and sustainable program of exploration with commercial and international partners to enable human expansion across the solar system and to bring back to Earth new knowledge and opportunities." The effort intends to more effectively organize government, private industry, and international efforts toward returning humans on the Moon and laying the foundation of eventual human exploration of Mars.

On 26 March 2019, Vice President Mike Pence announced that NASA's Moon landing goal would be accelerated by 4 years with a planned landing in 2024."
Although full funding approval is still pending and NASA is already requesting additional funds, the Trump Administration has already requested $21 billion from Congress.

V. Technology:  Furthermore, a lunar first program is at least feasible using SLS rockets, Orion capsules and essentially the same technology that supported the International Space Station (although innovations such as 3-D printing are constant improving capabilities).  Even the most wildly optimistic Martian plans (Mars One, for example, or Elon Musk's SpaceX) admit that the rocket technology is not yet available to handle the payloads necessary for a 3-year Mars mission, much less supporting a launch from Mars for the return trip.

VI.  Visible from Earth:  A lunar colony can and should be visible from Earth, allowing for an observable achievement of appreciable scale- which should improve Terran pride and support for lunar colonization long term.  Colonial observability also offers improved promotional opportunities- advertising, perhaps or celebratory displays on New Years, etc.

VII.  Practicing for Mars:  Space exploration is going to be very expensive and very dangerous.  Costly failures are an inevitable part of exploration.  We should consider the dampening effects of failure on the potential progress of space exploration and adopt an incremental approach towards success: improving confidence and support as we achieve one spectacular success and build upon that success towards the next.   

Colonizing the Moon first is cheaper, easier to plan, safer, and far, far more likely to succeed than any Mars mission currently under consideration.  Colonizing the Moon is not just a spectacular human achievement in and of itself, colonization allows us to discover and overcome many of the unforeseen obstacles of space exploration (including Mars colonization) in a near-Earth environment that is far more forgiving than any other objective in our Solar System.  Lunar colonization first should allow for major innovations and efficiencies in future Martian colonization and such a colony can even serve as a training and staging environment for Martian exploration, while the reverse is not particularly true.  Humanity is fortunate to have such a large natural satellite, rich in resources and pragmatically close by to exploit as a primary objective for space exploration.  We should take advantage of our Moon first as we make the Solar System and beyond human destinations and eventually, human habitats.

I look forward to CON's argument for a Martian first colony.

I am going to try a style and structure where Round 1 is mainly rhetoric, talking people into my case and such. I understand that any and all things raised without sourcing can be disregarded without them but if Pro chooses to one by one disregard everything, I promise that in Round 2 will be a powerhouse of rebuttals, references and reliable in-depth analysis of the debate, both logically, ethically and scientifically (physical facts as opposed to the 'logic').


PM = Planet Mars
TM = The Moon

Pro identifies as Other in profile so I refer to them with 'they/them/their' pronouns.

Risk vs Reward, Game Theory and How to Go About Calculating It

In this debate, neither side is necessarily denying that the other spherical entity should be colonised. This is about which should be colonised first, based on weighing both severity and probability of risks/drawbacks against the same factors for reward/benefits. This concept is known as game theory (GT).

I will not go into what GT is but I will be using the term GTO (O = optimal) to refer to the constant polar pull towards the side that I am saying GTO playing of the situation will result in.

The main reason I am clarifying how and why the Burden of Proof (BoP) works in this debate is so that I can then constantly establish how relevant, valid and/or weighted some points are against others. The perspective from which we are speaking is actually going to be a major factor in the debate and I notice that throughout Pro’s debate, they speak very much from the perspective of Earthlings only, refusing to recognise the new colony as a culture and group of nations of their own. This will become a major factor throughout, but I will explain that GTO is from the perspective of ‘overall universe’ so to speak and will go into how trust and politics work as fundamentals.

GTsO will refer to suboptimal GTO.


Potential to Maintain Life, Explode the Potential of our Species and Discover New, Important Things

The nearly irrefutable thing to raise as a PM advocate is the potential of colonising it, as opposed to TM, is that the very fact we’ve been to the moon, seen nothing was there worth inhabiting or exploring and such render it a GTsO venture for colonisation. Of course GTO is relative to the value of other options at hand, so what does PM have better? What could honestly justify all the extensive distance, risks and such associated with it when compared with the ‘oh so safe’ venture of the moon, in comparison? 

Let’s begin at the fact we know to an extreme degree of certainty that both space experts and financial advisors to both governments and private institutions agree that the moon is a total waste of colonisation and even visitation. Those holidays Branson is offering don’t actually land you on TM, if they do, I’ll be surprised and plead ignorance.

For those who don't know there's an atmosphere on PM, it has conditions susceptible to life and even though all we've seen are green blobs, it is very possible that there's far more that could happen there if it were to interact with water, soil and some conditions we could induce. There is fallback though, a lot more than Pro is making out. The beauty of the venture to PM is that it's worth every cent even if we fail to colonise it. We can have parties that literally are thousand-dollar priced occasions and have part of it go to charity perhaps, in the middle of space in a really sci-fi nightclub. We know for a fact that the many billions we spent on going to TM are all wasted (that's why we never ever went back and Elon Musk etc. all are talking about PM if anything). We planted a US flag there, spent a lot of time realising that there's nothing there and are informed that it's bland desert-like emptiness throughout. There is essentially no atmosphere at all on the moon, no sky, no 'in between' but just a non-encased sphere to land on, or maybe there is but the pressure is barely perceptible... Outside of this debate, I'm a flat earther so forgive me for not knowing the exact things about it, it doesn't make much sense to me either but if it's all real, we absolutely ought to head for PM instead. There is guaranteed failure, lack of anything interesting and worth the investment with TM. So even if you invest only one billion dollars, it will be every single one absolutely down the drain.

PM and the venture towards it will involve a lot of research and time, it could take 5-6 generations of our species beyond now to achieve it in a true sense of visiting and colonising. It is going to have a lot of in-between that will benefit us massively. We could have greenhouses in the space stations, help with the issue of overpopulation and deforestation without inhibiting people's freedom to have sex as well as not needing to fight off medical advances that make us live longer despite still having children. We wouldn't need to fight new life if we could create room in and around our planet. We'd never know until it was too late that there was a hostile force coming in from PM towards us (which has proven to be the most likely outer-space sphere in our vicinity to have life), until it was too late. They could be fooling our satelites by tactical dodging or perhaps operate in ways that the sense of sight can't pick up within the range caught on camera that hits our humane yes on receiving it. We do not know for sure until we go there. On the other hand, we know that absolutely nothing useful is to be found on TM.


Seeing 'them' as the colonised is a brutal error of ethics and politics. Everything about the 'security' angle and all that goes along with 'keeping an eye on them' is abhorrent.

We are not colonising the humans who are going to PM or TM... THEY ARE THE COLONISTS! What on Earth is Pro speaking of when they go into depth about needing to monitor the colony and all that as if they are to be held beneath us in worth and moral integrity. We are not their overlords, we are sending our own trusted human beings to colonise the planet. It is no different to saying that you can't see someone two streets away from you right now so it's only worth colonising your neighbour's house. That is literally the logic Pro is using. 

The problem runs deeper than that, it's about thinking divisively and is a completely toxic mentality to enter a new planet with, considering there may be unforeseen alien life there that we must treat with respect and not with outright contempt. Imagine a world where the right-wingers are no longer yelling at us about aliens from outside coming in but from inside running out and furious that they are forming a new culture and have some privacy of their own? They will develop their own accents, food, idiosyncrasies and much more. Who are we to tell them 'your culture are belong to us, slaves! 😈' ???? 

That is not how I want our planet to approach outer space with, especially not our own kin-of-species going out there and exploring, creating and enjoying their time there. Let them be them, they are not Earth's property. I know what colonising is, I get it. They are the colonists, not the colonised. If they choose to relinquish our planet's control there and mantain a more independent nation-to-nation relationship, who are we to loathe them for it? They will barely have Internet at the start, we'll be assessing the worth of investing in satellites and all that jazz, they'll be bored out of their minds with little to do other than have fun in a very ironically unfuturistic manner (oldschool bonding, love, community etc). Let them be. 

They are far more likely to want war with Earth or betray us if we are brutal and iron-grip in how we let them explore and operate within their own physical and political landscape there, that will of course evolve beyond what we are used to or could have foreseen.


The Beautiful Future Ahead

In debating it is easy to either be too emotional or too pragmatic. I am not falling into the former trap in this, believe me. It is extremely pragmatic to see beauty where the alternative has none whatsoever. The security angle is a lie anyway, we only see one side of the moon at all times because it apparently spins exactly as fast around itself as it orbits us (don't look at me, I am a skeptic outside of this debate, I'm playing along with the notion that NASA is totally honest for this debate). 

Actually, even if the Earth is round and outer space is exactly as we're told, going back to the moon is more likely to cause some kind of riots form flat Earthers if they're proven wrong or from the world as a whole if it's proven that the moon landing was faked (despite the moon being real and as NASA describes it to be, overall). With going to Mars, the sheer time in generations and staggered progress will enable the species as a whole to become comfortable with the idea and have faith in NASA and the authorities by then with no such resentment for 'proving them wrong' or 'proving everyone else wrong' because you can't prove that the moon landing was faked by going to Mars (unless it's a flat-Earth scenario but even then you aren't going to disprove it with the new faking).

In all ways this plays out, we gain Intel, progress and have a horizon in the development scientifically, both in terms of space research, technology and ecology (massive greenhouse space stations, entire forests in space to go to for fruits, oxygen etc.) that it's a really wonderful notion that we venture towards Mars with the hopes of getting therr rather than re-wasting billions just to plant a flag on desert-esque land.
Round 2
Thx, RM, for your thoughtful reply  

PRO's plan is to separate CON's response into 3 sections:  

EXTRA- which will be mostly ignored
PRO MARS- which will be countered
ANTI MOON-which will be rebutted


  • CON preludes his arguments with a promise of more rhetoric, less sourcing.  VOTERS will note that "better sourcing" is one of the criterion for judging this debate.
  • CON suggests that his framework will rely on the concept of optimal game theory, which he will not define.  PRO has no objection.
  • CON notes on multiple occasions that CON has concluded that the Earth is flat.  This suggests a lack of familiarity with astronomical proofs to a degree sufficient to disqualify CON from this debate.  If, for example, CON is convinced that the Earth and Mars are not both in orbit around Sol or that huge amounts of the data gathered by NASA and other space explorers is necessarily false and corrupt, PRO wonders that CON would defend Mars as a candidate for colonization.  If the Earth is flat, then all of Astronomy's fundamental assumptions and calculations after Copernicus must be false and any expedition to Mars based on those calculations and assumptions doomed to failure.  PRO has no wish to derail this debate rehashing some profoundly discredited theory so PRO will disregard, confident that such assertions can only undermine CON's credibility.
    • CON claims that any new space travel will create political turmoil as either flat-earthers or science will be proved wrong.  PRO notes that flat-earthers were proven wrong by Aristarchus of Samos in the 3rd century B.C. Any sincere flat-earth theory since serves only as an act of faith, immune to any evidence. 
  • In spite of the debate condition excluding political considerations, CON has engaged in some highly speculative political arguments regarding the sovereignty and rights of any Martian colony which PRO will disregard as irrelevant to this debate.  PRO assumes that the 1968 Outer Space Treaty will define the governance of all Outer Space settlements in the near term.
    • CON claims that PRO argued for the need to monitor colonies.  PRO objects to the obvious falsehood of this straw man.
    • CON argues for Martian independence irrelevantly and in contradiction to debate terms.  PRO will disregard this line of thought.

For those who don't know there's an atmosphere on PM, it has conditions susceptible to life and even though all we've seen are green blobs, it is very possible that there's far more that could happen there if it were to interact with water, soil and some conditions we could induce
  • PRO agrees with CON that Mars is more conducive to life than the Moon. 
    • Humanity should determine with better than 99% certainty that no life exists now on Mars before any human expedition, much less colonization.  As humanity learned soon after the discovery of the New World, biological organisms gradually develop tolerances for foreign organisms and are often highly vulnerable when exposed to new environments (Native Americans' vulnerability to smallpox, for example). 
    • If there is life on Mars, that life must be meticulously quarantined and studied until we are confident that exposure to Terran biologicals do not represent an unacceptable health risk to Martian life and that Martian biologicals do represent an unacceptable health risk to Earthlings. 
    • Since such certainty for Mars is likely decades away while the Moon already enjoys high confidence of sterility, the Moon is a superior candidate for first colonization while we are carefully looking for Martian life.  "No expedition to the moon has ever found amino acids or other chemicals that might link up to form living things, even as similar chemicals have turned up as far away as Mars."
"We'd never know until it was too late that there was a hostile force coming in from PM towards us (which has proven to be the most likely outer-space sphere in our vicinity to have life), until it was too late"
  • PRO seems to be arguing that intelligent life may eluding detection out of hostile intent.
    • CON argues that any such alien intelligence ought to have a sovereign claim to Mars, necessarily nullifying any Terran claims.
"We can have parties that literally are thousand-dollar priced occasions and have part of it go to charity perhaps, in the middle of space in a really sci-fi nightclub"
  • PRO agrees with CON that interplanetary fundraising parties are one potential (but fairly incidental) benefit of interplanetary travel.
    • PRO offers no reason why parties are a particularly "Mars first" development.  The Moon ought to prove a superior party venue because
      • Excessive travel time is a major downside to any party, particularly during the "hung over" return trip.  As PRO pointed out in R1, Mars takes 90 times longer to travel to/from than the Moon.  Therefore, we could theoretically host 90 times as many lunar fundraising galas per party bus/spaceship deployed.
      • Likewise, if we want any money to actually go to the benefit of charities, we should keep costs low.  Lunar fundraisers are going to be way, way cheaper than Martian fundraisers.  If we use NASA's cost ratios from R1 (24 unmanned/8 manned lunar missions= $20 -30 billion vs 1 manned martian mission = $500 billion.  Assume unmanned much cheaper- rough average $2 billion per manned mission vs $500 billion, or 1:250 moon:mars cost ratio), we could host hundred of lunar fundraisers for the cost of one Martian fundraiser.
        • Also, ticket prices in the thousands are simply not going to cut it.  At current prices, it costs about $1.7 million just to get the weight of the average US woman into orbit.  So, let's say a ticket to party on the Moon costs $3 million, we should assume that a ticket to party on Mars needs be about $750 million- really only a realistic consideration for maybe two or three thousand people on Earth, most of whom are probably too busy to spend most of their fortune on an 18 month joy ride.
"We could have greenhouses in the space stations, help with the issue of overpopulation and deforestation without inhibiting people's freedom to have sex as well as not needing to fight off medical advances that make us live longer despite still having children. We wouldn't need to fight new life if we could create room in and around our planet" 
  • PRO fails to explain why any of these options are exclusive or superior in a "Mars first" scenario.
    • Greenhouses are theoretically possible, in fact necessary to any long term settlement.  The Moon enjoys a considerable advantages over Mars as a location for hosting greenhouses.
      • Lunar regolith is mostly basalt- gritty and abrasive but theoretically useful as medium for soil.
      • Martian regolith, on the other hand, is deadly poison:
"Martian soil is toxic, due to relatively high concentrations of perchlorate compounds containing chlorine....  The levels detected in the Martian soil are around 0.5%, which is a level considered toxic to humans.  These compounds are also toxic to plants. A 2013 terrestrial study found that a similar level of concentration to that found on Mars (0.5 g per liter) caused:

  • a significant decline in the chlorophyll content in plant leaves,
  • reduction in the oxidizing power of plant roots
  • reduction in the size of the plant both above and below ground
  • an accumulation of concentrated perchlorates in the leaves
The report noted that one of the types of plant studied seemed resistant to the perchlorates and could be used to help remove the toxins in its environment, although the plants themselves would end up containing a high concentration of perchlorates as a result."

  • CON agrees with PRO that space colonies might offer some relief to the Terran problem of overpopulation (and, by extension, deforestation).  However, colonies with capacities of scale sufficient to be alleviate Earth are centuries away so and beyond the scope of our discussion here, which is where to build the first colony.
    • Even in the long term, the Moon's proximity and cost advantages make the Moon a more appealing destination for population relief efforts on any scale.

CON only has one vague anti-Moon argument.  CON restates the same unsubstantiated claim in four different paragraphs:

 "we’ve been to the moon, seen nothing was there worth inhabiting or exploring"

"space experts and financial advisors to both governments and private institutions agree that the moon is a total waste of colonisation and even visitation"

"We know for a fact that the many billions we spent on going to TM are all wasted "

"There is guaranteed failure, lack of anything interesting and worth the investment with TM. So even if you invest only one billion dollars, it will be every single one absolutely down the drain"
  • CON's claim is inexplicably ignorant of the profound ongoing scientific, financial, and geopolitical interest in the Moon.  
    • Wikipedia lists 137 missions to the Moon led by seven different nations over the last 60 years including 8 missions currently in progress.  India tried (unsuccessfully) to land a rover on the Moon last week.  China successfully grew a cotton plant from a seedling on the Moon earlier this year.
    • As stated by PRO in R1, NASA's ARTEMIS program has planned and partially funded 32 lunar missions over the next decade.  ARTEMIS 1 is scheduled to orbit the Moon next year.  The first manned mission is scheduled for 2022 and the first manned touchdown at the Moon's South Pole is scheduled for 2024.
    • Motley Fool was just salivating a few weeks back over Baylor University's recent discovery of a mass of metal 5 times the size of Hawaii's big island.  Chinese rovers are already looking for signs of gold there.
The Moon, in fact, is booming- one might even conclude that the preliminaries to colonization are already under way.  CON, it seems, is out of the loop.
R = Round
Abbreviations from R1 are still relevant.

Colonising the moon isn't remotely the same as extracing metals, growing cotton etc. There is even conflict of Interest in trying to inhabit and have an environment in a place you want to efficiently extract resources from in maximal capacity.

On the moon, there's no air to breathe, no breezes to make the flags planted there by the Apollo astronauts flutter. However, there is a very, very thin layer of gases on the lunar surface that can almost be called an atmosphere. Technically, it's considered an exosphere.

In an exosphere, the gases are so spread out that they rarely collide with one another. They are rather like microscopic cannon balls flying unimpeded on curved, ballistic trajectories and bouncing across the lunar surface. In the moon's atmosphere, there are only 100 molecules per cubic centimeter. In comparison, Earth's atmosphere at sea level has about 100 billion billion molecules per cubic centimeter. The total mass of these lunar gases is about 55,000 pounds (25,000 kilograms), about the same weight as a loaded dump truck. Every night, the cold temperatures mean the atmosphere falls to the ground, only to be kicked up by the solar wind the following days.

(content is backed up by what's said in this source, if you wish to get a second opinion) 
Our moon is uninhabitable and lifeless today. It has no significant atmosphere, no liquid water on its surface, no magnetosphere to protect its surface from solar wind and cosmic radiation, no polymeric chemistry, and it is subject to large diurnal temperature variations (e.g., Vaniman et al., 1991; Schulze-Makuch and Irwin, 2008). Thus, associating our Moon with habitability seems outrageous, and certainly it would have been just a decade ago. 

It goes on to say 'but maybe, just maybe it did host life before' essentially.

TM lacks any 'real' atmosphere, it has basically a tiny layer of slightly pressurised air that's some kind of bubble around it but overall the atmosphere is negligible, you surely can't host human life on it in any natural capacity. To do so would require even more resources than would go into a space station floating further away from the moon, because you'd need to build it to be weak enough to stay put on the moon's surface but sturdy and thick enough to withstand the atmosphere etc. The sheer insanity of aiming to live on the moon is justified solely by one overall thing:

To have a test-run for PM (or so says Pro). In other words, Pro concedes that the single most important reason to even begin considering colonising the moon would be that ultimately the best place for us to colonise in outer space is Mars but Mars is too far to have an easy test run. So, instead of making a room and such that can mimic Mars' atmosphere, gravitational pull etc, we are to assume that TM is the best way to spend money that could be spent on feeding people, alleviating poverty and solving many Earth-specific issues rather than a multi-billion dollar project that we already know will fail?

Let's be clear, we know (genuinely know) that colonisation of TM will fail as it has no capacity to host genuine life outside of artificial environments on it. This cotton project is nothing more than an experiment where FILL IN GAP HERE

On Earth, as is, we have already begun to see what happens when you extract resources heavily from a place you inhabit; the two motives hurt one another.[3] The environment and life get harmed the more that you extract from it;[3][4] not just in terms of sustainability, from the loss of resources, but also from the waste products and such form the means of extraction and energy production for such machines and processes). If we were to inhabit TM, reproduce on it, massively populate it and fight hard with technology to force life and environmental-hosing-capacity on a sphere that naturally has no atmosphere or life-enabling capacity whatsoever, we'd fail even if we succeeded because we are running a severely GTsO contradiction of motive and endgame. Do we want to extract from TM in a way that highly would harm us if we did it on a planet that we and fellow wildlife inhabited? Not if we know what's good for us and good for the extraction processes too.

What is even in it for us to inhabit when Pro so passionately makes 2 Rounds of debate about why we shouldn't inhabit and create life-based environments on TM? The only actual benefit listed is that it's easy to evacuate and rescue, which will absolutely be necessary and I agree to that benefit... The reason being that TM is guaranteed to be terrible at hosting life and all our motives for being there and getting this 'endless solar energy' is to power the machines that extract resources or carry out experiments that would otherwise damage the atmosphere and our own planet if we were to do them on Earth. I agree with Pro on so many of the benefits of Moon exploration, where I disagree is that we should colonise it due to all the better ways to use it that have conflict of interest with our colonisation of it.

Even the endless solar energy would be great if we didn't live on TM, to mass-garner etc, because one of the major drawbacks of solar energy is the waste products[5] it leaves behind and requires in order to properly maintain the panels. On TM, if we don't inhabit it, we can have waste products without mercy, ooh yeah baby!


So much to fall back on if colonisation on PM fails, defence will be an absolute better potential benefit.

It's GtsO to explore TM further with respect to colonising it or contemplating living on it in any long-term manner because we already know that in all such capacities, it is terrible. Mars not only has shown signs of harboring life, but even if Mars itself has no sinister and/or advanced aliens on it, we have absolutely proven that venturing to TM doesn't open up communication with aliens or help us assess the potential enemy further. Alternatively, PM could be a place aliens have been watching, perhaps from Saturn, and finally we meet them.

What is GTO is to meet them as soon as is feasible. The sooner you meet them, the sooner you can build a bond, trust, worth in their eyes as an ally that's reliable (if nothing else) such that you minimise their urge to hurt you. On the flip side, they are less far in their progress technologically, war-strategy etc. than they'd otherwise be and thus make as weak an enemy as possible, relative to the future version of them that you'd have otherwise met for the first time in alternative timelines where you stall visiting and genuinely exploring Mars as a species. 

If we never meet any aliens whatsoever, that still was the best play. We can't have a single way of knowing for sure that they aren't there or aren't waiting to attack, unless we go there ourselves and get assurance. The plethora of space stations, technologically developments and such that would happen and occur between Earth and Mars (literally between) would become failsafe holiday destinations, Space-forests for ecological purposes, and much more. They would help us extend out as a species into what could be a fantastic two-planet arrangement at best (actually at best we inhabit another one or two on top of that) or at worst it just becomes a resource-extraction, experimental playground like TM is for us (as Pro so vememently points out).


Whatever you think TM is rich in, there is far more of many other things on PM.

PM is bigger than TM (Pro happily clarified just how disproportionately bigger it is in R1) and there's a lot to find in it. Every single point that Pro raises about extracting from TM and such missions, all backfires onto Pro's side of the debate. Again, this debate isn't about extraction of materials but actual colonisation, which according to the description of the debate entails long-term habitation and reproduction on the spherical entity. If we are to play this GTO, why would we colonise the place we know is absolutely terrible for us to do anything other than extract resources from without mercy? Surely it would be wiser to go for the place that has such higher size, diversity of materials and thus promise of culminating all our time and effort into a fantastic pay-off at the end of the day.

It may not be rich in metals like TM, but I don't really think it's a mystery that a planet like that will have a massive bank of resources and such for us to explore, use for research and/or enjoy. We already know what TM has, it's just a matter of using it. PM holds endless possibilities for us, imagine we find a metal or specific kind of rock that reacts with copper or something in a way that makes supercomputers or helps machine, even factories and car engines, run far more efficiently and thus eco-friendly as they require less resources for the same output. There's a panacea of possibility on PM, it dwarfs the moon in every department of probable pay-off for visiting it long-term and colonising it, resources included.


What exactly makes the Moon a good test run for Mars in the first place?

Perhaps the least GTO aspect of moon-colonisation is that is is nothing like Mars at all other than being a sphere. It lacks atmosphere, has such an extremely weaker gravity than Mars does/will and (therefore) all the billions spent on it are not just wasted for all the reasons stated so far by me in this debate but the endgame is so utterly defeated from the reason of its pursuit. We will not be living on TM, because it can't harbor life, we won't be better off for colonising PM, because other than having sex outside of Earth and experimenting with how to have healthy offspring and such, there's next to nothing in common with the colonisation of TM and PM.

Round 3
Thanks, RM, for an excellent bout

So far, CON's argument in favor of Mars has been pretty vague- relying more on denying the value of the Moon as a potential colony than explaining Mars' positive advantages.   PRO assumes as NASA does, and most past writers of science fiction and  science fact, that both the Moon and Mars will support human colonies in time.  The question before us is which stellar object to focus on first.

VOTERS will recall that PRO has offered 7 reasons to build a Moonbase first:


  • CON has not refuted that the Moon's nearness offers major advantages over Mars in terms of  faster and cheaper health & safety support, evacuation & rescue times, tourism, employment availability, communication and media availability, resource extraction and transportation.  CON has dropped six R1 arguments favoring 30 times faster travel times and perhaps 250 times cheaper startup costs.

  • CON has ignored PRO's argument that the Moon's low gravity and mineral wealth make the Moon the best possible choice for a spaceport beyond Earth's already overcrowded orbit.

  • CON disregarded PRO's arguments regarding the advantages the Moon has over Mars in terms of highly predictable whether and a regions of continuous light and continuous darkness.


  • CON has dropped PRO's evidence that NASA has made its preference known and has already allocated significant resources towards supporting 32 new missions to the Moon over the next decade.

  • CON has made no reply to PRO's argument that the rocket tech necessary to colonize the Moon is presently available while the rocket tech necessary to colonize Mars has not yet been invented.

  • CON dropped PRO's discussion of the promotional advantages of a human colony visible from Earth.

  • CON tries to claim for his side PRO's arguments that success on the Moon can improve human confidence, investment, and capacity for exploring Mars and other destinations in space.
"Pro concedes that the single most important reason to even begin considering colonizing the moon would be that ultimately the best place for us to colonize in outer space is Mars but Mars is too far to have an easy test run."
That's right-  Mars is far.  The Moon is near.  The Earth will need a staging area first, a spaceport beyond Earth's already overcrowded orbit from which to launch exploration and supply vehicles.  The Moon is well positioned to support such a spaceport while Mars is out of range 25 out every 26 months and when it is in range costs something like 250 times more than the Moon to explore and resupply.  We can bring those costs way down by starting with the Moon- developing the tech and extracting the resources necessary to survive the harsh environment of Mars by problem-solving an even harsher laboratory  that's cheap and close.

CON went on in R1 to claim that there was nothing of value on the Moon and that any investment is wasted but when PRO countered with the significant current interest and investment in the Moon- 7 national programs, 8 ongoing missions, PRO dropped the argument in R2.

By PRO's count- that's 12 pretty solid arguments ignored by CON.  For our single point of contention, PRO and CON agree that Mars is ultimately the more livable, productive location but PRO argues that going straight to Mars is extremely expensive and risky- costs and risks that can be profoundly mitigated by using the Moon as a stepping stone.


  • The flipside of Mars viabiltiy (presence of water, amino acids, etc) is that there may already be life (CON even suggests intelligent life which PRO says makes Mars off-limits).  We must rule out with a high degree of confidence any potential life (as we have done on the Moon ) before setting any timeline or promoting Mars as a potential first human colony.

  • PRO suggested the possibility of fundraising parties on Mars but never explained why distance and cost don't make the Moon a preferable party destination.  PRO dropped the matter in R2.

  • CON talked a bit about Martian agriculture but never addressed PRO's concern about the deadly toxicity of Martian soil.

  • PRO and CON both agree that after generations of trial and error and probably some terraforming, Mars will likely be the more suitable place for large-scale Terran migration but that's not the question.  The question is where shall we colonize first?  The fact is that we are going to have to have significant lunar development anyway and all the effort we put towards lunar development will certainly improve martian success rates and martian costs so the Moon is simply the most rational choice for a first colony.

  • CON argues that we should have mining and agriculture on the same Moon with a colony but we do both on Earth and it will likely be a few centuries at least before we can afford to have "mining planets" like in Star Trek.  PRO assumes that industry and habitation will share the same moons and planets for a long time to come.

CON has argued that the Moon has no atmosphere but also that the Moon has a very thin atmosphere.  CON has also argued that surface dwellings on the Moon offer significant design challenges.  PRO counters that most lunar colony designs tunnel under the Moon's surface, using a thick layer of rock to protect inhabitants from solar radiation and massive temperature shifts.  All lunar colony designs assume an artificial atmosphere, perhaps employing oxygen extracted right out of the Moon's rock which is unusually rich in captured oxygen.

CON seems to suggest that Mars is preferable because there's a chance to live outside of artificial environments but PRO is not aware of any serious proposal that suggests the possibility of human life outside of habitats without millennia of terra-forming.


CON argues that Mars is more likely to be richer in natural resources and PRO agrees but the Moon's lack of gravity makes redistribution of lunar resources super cheap compared to the cost of launching harvested material out of any planet's gravity well.  A ton of iron mined on the Moon can be smelted and refined on the Moon and used for industry or spaceship building for very little transportation cost, maybe a few thousand dollars  A ton of iron mined on Mars would likely cost tens of millions of dollars to get into space for spaceship building or export elsewhere.  The same principle will prove true of water, oxygen, hydrogen fuel, solar-charged batteries, etc, etc, etc.  Once the Moon is up and running we can support Mars colonization at exponential savings costs.  Only a couple of Jupiter's moons offer the same kind of resource to gravity ratio as our lucky, blessed Moon and Jupiter's moons are 6 times further away than Mars at their closest approach, more than 500 times more distant than our Moon.


CON's argument for Mars depends on the false assumption that Mars' superior size and atmosphere and water will somehow translate into a more comfortable and verdant colony but that's not so.  As with any near future space colony, Mars or the Moon is going to look a lot more like the International Space Station buried underground than it will "Avatar"'s Pandora.  We are going to need a lot of radiation shielding and  microgravity physical therapy.  Colonists will likely spend their lives in fairly confined spaces humming with computers and machinery and stinking of chemical toilets and fried wires.  Most of CON's argument looks past this stage of development and assumes the slightly less hostile environment of Mars will translate into greater comfort but that's just  not so-  the atmospheric pressure on Mars may be greater than the Moon or in space but in all three environments a human blood will boil away in a few short seconds.  

And for every way to day in space that we know of, there will likely to be five other ways to die that we simply have not thought of.  As with previous cycles of human exploration, we can predict that many people are going to die in many unpredictable ways.  The big advantage of the Moon is that proximity will give us humans to save some people under some conditions, proximity will make the dangerous undertaking cheaper and faster than the same dangerous undertaking much further away form Earth.  Lower gravity will make resource mining cheaper to extract and cheaper to forge into tools, machines, ships, and robots.  The moon's predictability will help eliminate some of the uncertainties of Martian dust storms and unpredictable Martian solar energy.  Either way, colonization is likely to be messy and polluting and destructive in its early stages- all of which is easier to clean up and control on the Moon, especially if Mars proves to have any residual life.

There are many unknown variables in our quest for a space colony but what we know for sure is that colonizing the Moon is way cheaper, way closer than any other option.  The Moon is so close and cheap that it makes a good platform for launching future explorations, future colonists.  Since any development on the Moon likely reduces the cost and risk of all future space exploration,  the Moon is the most rational choice for colonization first.

For all these reasons, VOTERS should find PRO's argument favoring the Moon more compelling.

Thanks again to RM for his participation, I look forward to his closing argument.

Thanks also to VOTERS for their kind consideration.  
Please vote PRO.

I will make this very simple. The reasons given by Pro were not to colonise the Moon, but to extract resources from it and experiment on it.

There has been zero explanation of why, despite how completely different they are, that spending many billions of dollars' worth on a 'test run' on the Moon will in any way actually prepare us for colonising Mars, it will just waste money and time.

The Moon is guaranteed to have zero pay-off for the investment, you literally cannot learn how to colonise Mars from colonising the Moon, they are so utterly different. 

The Moon is inhabitable, it's a waste of time to colonise and all the reasons that Pro gave, backfire. After all, we can more efficiently and without mercy extract resources and experiment on the Moon if we don't have life and an environment there to kill and destroy.

It's that simple.