If i may add my 5 cents to this:

• What do you think is the most profound and captivating reason(s) that you have to justify SpaceX and Elon Musk's goal of making humanity a multi-planetary species?

--> Depends how you want to see Elon Musk: as the visionary who wants humanity to thrive and improve? Or just as the one who seeks fame and fortune for being the first in doing things?

In my humble opinion, humanity has yet to reach a level of mindset to overcome cultural and religious differences. We might have satellites and smart phones, but in our thinking we still behave like cave-men.

For example, the Americans, when setting foot on the Moon, put an American flag there. Not one showing Earth. How would it be on Mars, when Chinese, Indians, Europeans and Americans set foot there? Whom will it belong to? For sure not the entire humanity, so we would just bring all of our archaic thinking into a new world. All our problems and issues, and soon the new planet will suffer all the same problems as we have on Earth.

As long as we do not manage to live as one humanity on one planet (i.e. having a global government), there is no point in making humanity multi-planetary.

• What are the ethical considerations we must address before colonizing other worlds?

--> As mentioned above: if you want to colonise something, who does it belong to? Is there indigenous life (whether intelligent or not)? Or is it a barren rock?

Now given the barren rock case: Who does it belong to? Imagine it has a huge amount of rare minerals on it. Is it "whoever finds it can keep it"? In the outer space treaty from the 1960s, they addressed this topic, saying that space belongs to all humanity, yet not all nations have signed this and yet when it comes to mining/farming/inhabiting these space environments, how is that regulated? And if violated, who prosecutes the violators?

There is a huge legal issue in regards to occupying space environments.

Now given the planet is not a barren rock, but an obviously inhabited planet: Now we can either develop yourselves as species and not touch the ecosystems of these planets, leaving them pristine for the indigenous life. Or we can act in the human way and do the same mistakes as we did in the past over and over again and just go there, exploit and trash the planet until its depletion.

The most difficult and realistic case is actually the case of Mars:

Why is Mars so interesting? Because in its past it was very similar to Earth, it had a denser atmosphere, a magnetic field, volcanism, starting plate tectonics, liquid water and all chemical ingredients for forming life. Mars might have gone through a similar evolution as Earth, forming microbial life, or maybe even be the origin of terrestrial life, as interplanetary transportation of rocks after impact events is proven to occur. Now, Mars is the perfect (and maybe only) place to actually study how life on Earth could develop and if life could develop on other planets as well, if life is unique or if it appears quite common throughout the universe.

But, if we send now a bunch of colonists there, who will bring lots and lots of organic material from Earth, we might spoil Mars to a degree where we cannot study this anymore, loosing a very unique opportunity.

Given the case there is still life around, wouldn't it be best to first study it, before building houses, schools and hospitals next to it?

And then there is another ethical consideration that needs to be taken into account:

Sending colonists to space with current technologists would use up significant amounts of terrestrial resources. Sending just 30000 colonists to Mars would already use up all the remaining mineral oil reserves on Earth, not to mention the metals, materials, supplies, etc shipped with the settlers. In order to send these few privileged people to Mars, the rest of humanity will have to sacrifice their lifestyle, their future and their environment. Is that ethical?

• Do humans really deserve another planet to potentially ruin, or even sustainably terraform, if we cannot even figure out how to sustainably balance our own home world?

--> If we could terraform Mars, why not first terraform Earth? Reverse the effects of climate change, stop and reverse desertification. Earth is better studied than Mars, but as long as here high-ranked people make money with pollution and deny scientific facts, nothing will happen for the better. The money that Musk wants to spend on the colonisation could as well be spent to cover parts of the Earth's desert areas with solar power plants, providing humanity with CO2-free energy. That would benefit more people.

Also, terraforming Mars will not be sustainable. Mars is loosing its atmosphere, because of the lack of a global magnetic field. it might become a home for a while, but thinking into the far future, Mars will be back to where it is now.

Plus, how do we know we can potentially manage to create stable living conditions on Mars, when we are all about destabilising every environment we enter?

• One might ask why doesn't Elon use his genius to create new technologies that will advance the human race by solving some of the Earth's worst problems?
• Has he simply given up on this planet and does he therefore want a clean slate to build up from?

--> Maybe because it is easier messing up something new, rather than fixing something old?

• Does Elon think that technological advancements resulting from the drive to become a spacefaring civilization (i.e. propellant production via. CO2 sequestration powered by 100% solar energy systems) will eventually rebound to help the Earth?

--> Musk's rockets use RP1 (refined kerosine) like all other rockets, and as long as this remains the cheapest fuel, nothing will change. Rockets are basically 95% fuel that is burnt. Using synthetical fuels is a huge cost factor. And especially since the CO2-concentrations (despite being high enough to significantly influence the climate) in the atmosphere are too low for economical use, I do not see any of this happening any time soon.

• Must we start colonizing Mars now (i.e. beginning in the year 2022) like Elon's timeline suggests? Potentially, if we wait too long, technologies to reverse climate change on Earth may not have advanced enough without the excitement of being spacefaring...

--> No. We need to politically, economically and ecologically get our shit together first. We need to all reduce our negative imprint on the environment on Earth, foster international collaboration not wars, fear or hate, we need to change our thinking not towards maximising the monetary output, but in maximising our own happiness and humanity towards others.

Also, we should (must) explore Mars first. The right step is to first send a small groups of astronauts to carefully study Mars (and come back) over an extended period of time (~20 years) to really answer all our open scientific questions, before we can even think of inevitably spoiling the pristinity of the planet.

==> this would be the right way, and would avoid many of the mistakes that human explorers on Earth have done in the past (i.e. settling at their first arrival to a new place)

The introduction of a new species (Homo sapiens) into an ecological system implies severe disturbances to its equilibrium. In the case of colonization of other worlds, this would be more than introducing a new species; indeed, it would be to try to impose a new dominant species.

In the case of terrestrial colonization, where it is not a question of introducing a new species but a new dominant culture, this being less dramatic than the case of introducing a species, we can nevertheless observe that the effects are still profound.

I think that in the human being we can find different types of colonization:

1.- Convergent colonization:

When with the passage of time the colonizing culture is mixed with the elements of the colonized culture, giving rise to a new identity. It is the case of Latin America, for example, where Hispanic cultural characteristics have been mixed with strong native cultural elements, creating a well differentiated identity of the Hispanic and the native. The case of the Roman empire is interesting in both the use of "forced absorption" tactics, where conquered peoples were frequently dispersed in different provinces of the empire, local deities added to the Roman pantheon, and territories were populated by Roman citizens, forcing effectively a rapid integration process.

2.- Divergent colonization:

When the colonizing culture is dedicated to isolate the native elements, often using them as a work force but without propitiating the cultural or biological mixture. This is the case of South Africa and the United States of America, where native populations have been more or less successfully confined to reserves.

3.- Excluding colonization or extermination

When the colonizing culture definitively extinguishes all trace of native population, this occurs in cases where the native population would have been scarce from the beginning, or in cases of extreme xenophobic colonizers. Historical examples are rather old, when conflict arose between city-states, prior to the development of the nation-state. The more "advanced" cultures usually prefer to use the native culture as providers of labor.

In the case of planetary colonization, the impact of our hypothetical invasion may vary depending on the degree of evolution of native organisms. By force we would have to speak of a civilization or forms of life with less technological or tactico-military advance, otherwise the conquered would be us. In all other cases, the evolution of native organisms would be profoundly affected, since colonization would not be exclusively human, we would take with us useful domestic species (cattle). The evolution of native species would have to adapt to the new conditions imposed or face extinction (as in the case of the ecological imbalance caused by the fauna introduced by man in Australia).

Whether or not this would be ethical, I think it depends on the notion of ethics. The big problem is that ethics as we handle it is a human term, applicable to humans, and therefore will tend to favor our views as a species.

In my opinion, I think it would be rather cruel for us to colonize an inhabited planet, although if the end of this colonization is to preserve the human species then any ethical notion will be overcome by this need for survival and durability in time.

Another option, perhaps the most appropriate one, would be to stay on Earth and try to improve the quality of life of the human species, that is, making reasonable use of the resources we have and mediating efficiently in the conflicts that happen.

If i may add my 5 cents to this:

• What do you think is the most profound and captivating reason(s) that you have to justify SpaceX and Elon Musk's goal of making humanity a multi-planetary species?

--> Depends how you want to see Elon Musk: as the visionary who wants humanity to thrive and improve? Or just as the one who seeks fame and fortune for being the first in doing things?

In my humble opinion, humanity has yet to reach a level of mindset to overcome cultural and religious differences. We might have satellites and smart phones, but in our thinking we still behave like cave-men.

For example, the Americans, when setting foot on the Moon, put an American flag there. Not one showing Earth. How would it be on Mars, when Chinese, Indians, Europeans and Americans set foot there? Whom will it belong to? For sure not the entire humanity, so we would just bring all of our archaic thinking into a new world. All our problems and issues, and soon the new planet will suffer all the same problems as we have on Earth.

As long as we do not manage to live as one humanity on one planet (i.e. having a global government), there is no point in making humanity multi-planetary.

• What are the ethical considerations we must address before colonizing other worlds?

--> As mentioned above: if you want to colonise something, who does it belong to? Is there indigenous life (whether intelligent or not)? Or is it a barren rock?

Now given the barren rock case: Who does it belong to? Imagine it has a huge amount of rare minerals on it. Is it "whoever finds it can keep it"? In the outer space treaty from the 1960s, they addressed this topic, saying that space belongs to all humanity, yet not all nations have signed this and yet when it comes to mining/farming/inhabiting these space environments, how is that regulated? And if violated, who prosecutes the violators?

There is a huge legal issue in regards to occupying space environments.

Now given the planet is not a barren rock, but an obviously inhabited planet: Now we can either develop yourselves as species and not touch the ecosystems of these planets, leaving them pristine for the indigenous life. Or we can act in the human way and do the same mistakes as we did in the past over and over again and just go there, exploit and trash the planet until its depletion.

The most difficult and realistic case is actually the case of Mars:

Why is Mars so interesting? Because in its past it was very similar to Earth, it had a denser atmosphere, a magnetic field, volcanism, starting plate tectonics, liquid water and all chemical ingredients for forming life. Mars might have gone through a similar evolution as Earth, forming microbial life, or maybe even be the origin of terrestrial life, as interplanetary transportation of rocks after impact events is proven to occur. Now, Mars is the perfect (and maybe only) place to actually study how life on Earth could develop and if life could develop on other planets as well, if life is unique or if it appears quite common throughout the universe.

But, if we send now a bunch of colonists there, who will bring lots and lots of organic material from Earth, we might spoil Mars to a degree where we cannot study this anymore, loosing a very unique opportunity.

Given the case there is still life around, wouldn't it be best to first study it, before building houses, schools and hospitals next to it?

And then there is another ethical consideration that needs to be taken into account:

Sending colonists to space with current technologists would use up significant amounts of terrestrial resources. Sending just 30000 colonists to Mars would already use up all the remaining mineral oil reserves on Earth, not to mention the metals, materials, supplies, etc shipped with the settlers. In order to send these few privileged people to Mars, the rest of humanity will have to sacrifice their lifestyle, their future and their environment. Is that ethical?

• Do humans really deserve another planet to potentially ruin, or even sustainably terraform, if we cannot even figure out how to sustainably balance our own home world?

--> If we could terraform Mars, why not first terraform Earth? Reverse the effects of climate change, stop and reverse desertification. Earth is better studied than Mars, but as long as here high-ranked people make money with pollution and deny scientific facts, nothing will happen for the better. The money that Musk wants to spend on the colonisation could as well be spent to cover parts of the Earth's desert areas with solar power plants, providing humanity with CO2-free energy. That would benefit more people.

Also, terraforming Mars will not be sustainable. Mars is loosing its atmosphere, because of the lack of a global magnetic field. it might become a home for a while, but thinking into the far future, Mars will be back to where it is now.

Plus, how do we know we can potentially manage to create stable living conditions on Mars, when we are all about destabilising every environment we enter?

• One might ask why doesn't Elon use his genius to create new technologies that will advance the human race by solving some of the Earth's worst problems?
• Has he simply given up on this planet and does he therefore want a clean slate to build up from?

--> Maybe because it is easier messing up something new, rather than fixing something old?

• Does Elon think that technological advancements resulting from the drive to become a spacefaring civilization (i.e. propellant production via. CO2 sequestration powered by 100% solar energy systems) will eventually rebound to help the Earth?

--> Musk's rockets use RP1 (refined kerosine) like all other rockets, and as long as this remains the cheapest fuel, nothing will change. Rockets are basically 95% fuel that is burnt. Using synthetical fuels is a huge cost factor. And especially since the CO2-concentrations (despite being high enough to significantly influence the climate) in the atmosphere are too low for economical use, I do not see any of this happening any time soon.

• Must we start colonizing Mars now (i.e. beginning in the year 2022) like Elon's timeline suggests? Potentially, if we wait too long, technologies to reverse climate change on Earth may not have advanced enough without the excitement of being spacefaring...

--> No. We need to politically, economically and ecologically get our shit together first. We need to all reduce our negative imprint on the environment on Earth, foster international collaboration not wars, fear or hate, we need to change our thinking not towards maximising the monetary output, but in maximising our own happiness and humanity towards others.

Also, we should (must) explore Mars first. The right step is to first send a small groups of astronauts to carefully study Mars (and come back) over an extended period of time (~20 years) to really answer all our open scientific questions, before we can even think of inevitably spoiling the pristinity of the planet.

==> this would be the right way, and would avoid many of the mistakes that human explorers on Earth have done in the past (i.e. settling at their first arrival to a new place)

Sebastian and Daniel:

Thank you both for your well thought out responses. I will let them marinate here for a little while before personally delving deeper into your answers. I agree with much of what you have both said, and I really appreciate the intellectual depth and accuracy of the answers.

Sebastian:

However, at the first glance I do see a flaw in your response. Musk's BFR rocket does not use RP1, they use CH4 and O2, which can both be created with the availability of CO2 and H2O powered by a renewable power source such as solar. If you watched Musk's recent presentation that I posted the link to, you would know this fact, and you would also know he is actually planning on carbon sequestration as being a large component of propellant production. I also disagree with your statement that terraforming Mars will not be sustainable because of atmospheric loss. In fact, the very nature of terraforming would combat this issue because the timescales of atmospheric loss due to the absence of a magnetic field would be compensated for by artificial pressure increase to reach a steady state between natural loss and artificial gain.

Best,

As a planet we have "conquered" most all the frontiers available. Just as we are a diverse planet in terms of both ecosystems and cultures, so are we diverse in the expectations, lifestyles, and contentment scales of what each of our environments provide. Some are content to stay home and work to improve that and others must reach for the excitement of the unknown, the next frontier. As a culture there have always been the forward thinkers who dreamed of being the "first". Many of our historical ancestors are in fact part of our history for being the first to do something on a grand scale. Some strive for that thrill of accomplishing what has heretofor been out of reach. Their goals are higher and grander that the reality of the rest of us believe are accomplishable. They want to experience things that others have not and live the impossible that others only dream about. It is for these people that we must push forward in attempting to achieve what has been the stuff of science fiction until now.

While I agree that we have messed up here on Earth quite radically, I am hopeful that in our next attempt at creating lives for ourselves elsewhere we will have learned from the mistakes made here. And any technology needed for that which trickles down to an improvement for our own global condition must surely be a added benefit.

The most profound and captivating reason? I can think of many reasons, to do with scientific and technological progress, destiny as a space-faring community, acknowledgement of our own origin in interstellar reprocessed materials.

But the #1 has to be: Self-preservation of our species.

Right now we have all our eggs in one planetary basket; all it takes is one "extinction level" asteroid hit to wipe us all out. Or perhaps one unstoppable virus.

And in the much longer term, we are going to have to migrate everyone outwards as the Sun evolves into a sub-giant.

Hi all,

First comment, if Elon Musk were the only one to care, maybe we could just forget the question. But it concerns the whole of mankind, so it is interesting to try to push forward at least one reason to follow on the space odyssey, be it throught the so called "New Space" approach or through other configurations...

Second comment, here comes the reason I rank one. To make it short : we are reaching the moment where the whole earth will be a small village. If we don't open doors and windows on new spaces (real spaces, but also states of mind) and new ressources, we will shrink into decaying and conflicting remains... We might not have a second chance.

This doesn't mean that I think that the goal is as near as one could think just listening Elon Musk. Never forget it's still a very long term endeavour. But it deserves a sustained effort.

Hi,

to briefly answer on your comment, Cole C. Pazar

"However, at the first glance I do see a flaw in your response. Musk's BFR rocket does not use RP1, they use CH4 and O2, which can both be created with the availability of CO2 and H2O powered by a renewable power source such as solar. If you watched Musk's recent presentation that I posted the link to, you would know this fact, and you would also know he is actually planning on carbon sequestration as being a large component of propellant production. I also disagree with your statement that terraforming Mars will not be sustainable because of atmospheric loss. In fact, the very nature of terraforming would combat this issue because the timescales of atmospheric loss due to the absence of a magnetic field would be compensated for by artificial pressure increase to reach a steady state between natural loss and artificial gain."

1) Do not underestimate the legal procedures to get a new engine system approved for flight, for use and even more for use with humans on board. The days of the "cowboy-style" Apollo era are gone. Nowadays everything has to be tested and certified several times over before finally becoming "flight hardware".

2) Producing fuel from CO2 and Water might be a good and efficient thing when you are on Mars, where you have an atmosphere of 95% CO2, but here on Earth, with currently 410 ppm is not efficient at all. It would be more efficient to produce methane from rotting biomass, but still, as long as we have cheap fossil fuels, this methane would still come from natural gas sources. The price per cubic meter is here what dictates the source, no matter what noble goals Musk has, in the end he will do what his stakeholders want: buy from the cheapest provider to make the most profit.

3) On another note: why not reusing the SSME type of engines? Since in the process of producing the methane you have to split up the water anyways, you could as well just use hydrogen and oxygen as propellants.

4) As I said, Mars might become a home for a while, but the atmospheric loss will continue and might be even increased by rising the atmospheric pressure and human activities on the planet. Imagine a balloon filled with water and you have a small hole in it. Putting more water into the balloon will just result in loosing more water.

So where from will you get more atmospheric pressure when you run out of resources?

The word "sustainability" means that you have closed systems, that you can reuse all resources and therefore do not exploit the planet. That is why such a colony would not be sustainable over long term.

@Carol Oliver:

As the saying goes "hope dies at last", but when you just take a look on nowadays' society, on politics for example: it seems many many voters have not learned from the mistakes of past generations. Nationalism caused one of the most horrifying wars in human history, including the deliberate killing of millions of innocent people, and yet you see nationalism sprouting again in many many countries.

This is the caveman still being inside us. And I do not believe you can eradicate this so easily within just a few generations. Maybe you send a group of idealists to colonise Mars and this generation might do a good job, but already the following generations might be falling back to greed for money, power, etc.

Such as many children and grandchildren of the Hippie generation are back to being businessmen.

@ Ray Butler:

The likelihood of such a global event is fairly low. Nowadays we are taking quite some effort to spot Asteroids and objects that potentially could hit the Earth and at least all the major ones are tracked.

Also that a virus will kill us all is not so likely. There is a great diversity among the human species and someone will be resistant to that virus, so I assume there would be a group of survivors.

More likely that we wipe out ourselves by pollution, nuclear wars, or other things like that. And this is something we will not evade when we go and take our cavemen mindset to other planets.

The sun is no issue at all. It will burn for another 3-4 billion years before there is a significant increase in the activity. By that time humanity will be long wiped out already, and if not, then for sure we would have settled throughout the galaxy.