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Building a Planet B for Humanity Isn't a Good Enough Reason to Explore Space

An artist's depiction of life on Mars.
An artist's depiction of life on Mars.
(Image: © NASA)

Listen to would-be space explorers for long enough, and eventually they will likely argue that humans must develop outposts on other worlds in case of disaster here on Earth, as a so-called Planet B.

But that's a dangerous narrative, said Kathryn Denning, an anthropologist at York University in Canada who focuses on the intersection of space exploration, humanity and ethics. It's not particularly feasible, either, by her calculation.

"The reality is, what would be needed to create a sustainable human civilization in the solar system that could effectively be a backup for humanity?" Denning said to Space.com. "That, for every kind of foreseeable future for, say, the next hundred years, requires a functioning and sustainable civilization here."

Related: Before We Find Aliens, Humans Need to Figure Ourselves Out

That reliance on Earth is not surprising considering how many characteristics of other worlds make them inhospitable or even threatening to humans. But the tie to Earth does throw a wrench in dreams of shuffling off our terrestrial coil — dreams that can be an attractive alternative to the difficulty of tackling the challenges of life at home.

"For me, the question is balance," Denning said. "How can we be enthusiastic about the human capacity to explore while maintaining our focus on what needs to happen here on this planet?"

Some approaches developed to address challenges of spaceflight can also shape life on Earth; NASA regularly highlights "spinoff" technologies you don't need to go to orbit to appreciate. Other challenges and solutions of space lack those spinoff applications.

Sometimes, the idea of a fallback world is stretched even further beyond the bounds of possibility, to places we can't pragmatically visit. "Amazing scientific discoveries, for example, exoplanets, get co-opted into problematic stories about our own life here on Earth. Exoplanets do get framed as a Planet B," Denning said. "That's become the story, that that is why exoplanets are important, because maybe we can go there when we've destroyed Earth." That reasoning ignores the scientific importance of studying these distant alien planets.

Transferring humanity elsewhere also has consequences for destination worlds. Some of those concerns are addressed by planetary-protection guidelines, which are designed in part to reduce the odds that terrestrial contamination will prevent scientists from being able to determine whether life exists on other worlds.

Still, Denning said she's not convinced that those guidelines are enough to protect either other worlds and any life there or even astronauts themselves. "I'm not saying Mars off limits forever or anything like that," she said. "In my ideal universe, we would just be slowing down and taking more time and making sure that we get it right for everybody's sake, for the sake of any humans you're sending out there as well."

Those concerns apply to exploration on the scale of just a handful of astronauts as well as to the more sizable and permanent migration implied by the term Planet B. But in both cases, humans have a lot of potential to change the worlds they visit, purposefully or accidentally. And Denning said she wishes we would spend more time now discussing what those worlds' futures may someday look like.

"We've got worlds out there that we haven't really messed up yet," Denning said, wistfully pointing out that if we're careful, we can keep them that way. "Wouldn't it be nice?"

Email Meghan Bartels at mbartels@space.com or follow her @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.

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  • mariop
    Admin said:
    Listen to would-be space explorers for long enough, and eventually they will likely argue that humans must develop outposts on other worlds in case of disaster here on Earth, as a so-called Planet B.

    Building a Planet B for Humanity Isn't a Good Enough Reason to Explore Space : Read more
    Well, I guess author would agree that current situation is optimal for humanity. Space exploration and colonisation of planet B is funded mainly by private companies so focus of society can stay on important things - how to make Earth better.
    Reply
  • manupupule
    I would argue that the pursuit of a so-called planet B would inadvertently create a sustainable planet A (earth) as a byproduct of that pursuit.

    Here is how I come to that determination. let's just pick mars as our nearest most technologically doable planet B for this example ok,

    Mars is very cold,
    Like VERY VERY COLD, mars makes Antarctica look like a sunny day. So if we are to move to mars we are definitely going to need insulation, and to make this venture economically viable we are going to have to make insulation orders of magnitude cheaper and better. As a result of us inventing a cheaper and better insulation the same company that patents that technology is going to want to sell that space-age insulation here on earth as well. So they first go to all the really cold and really hot places, and they sell their insulation to all new construction and as an external house wrap to all existing construction. so now homes use 1/10th the power to heat or cool the building. if all the buildings are able to use 1/10th the power we can reduce our carbon footprint on earth by a huge amount. and that's just one byproduct of going to mars.

    Now let's talk about food,
    if we go to mars none of the soil on mars can currently grow food, because mars soil is full of toxic perchlorates, so if there is to be a colony on mars we are going to have to develop a way of removing toxins from the soil in a fast cheap way. so let's say we get the top minds on earth focused on how to do this and they develop some sort of amazing nanobot that eats toxic waste and spits out pure oxygen.. then we could use that same nanobot technology to clean up the oil spills and other chemical spills here on earth.

    Let's talk about power
    ok so you get to planet b, and you are only a small team at first, but you have enormous energy demands because you are constantly welding and forging steel to build the city of tomorrow. you need a lot of power but there isn't much if any carbon to burn to make it happen.. so you extract water and use super-advanced electrolysis with some catalyst that breaks water apart into hydrogen and oxygen and you burn that instead for fuel.. you could then use that same technology to replace all the coal plants on earth. water power is the future!

    these are just three examples of which I know hundreds why in the process of pursuing a planet b we will become more sustainable on earth.
    Reply
  • R J Craigs
    It will take a long time to get to a Planet B situation. The figure of 100 years is hardly long term thinking. Cleaning up our own planet is very important but that is also short term thinking. Some planet scale disasters can only be survived by being somewhere else when they happen. We have all our eggs in one basket. We need to work on what it will take to establish a sustainable self supporting ecology and breeding population off-Earth. Our descendants, when faced with a planetary disaster will either be grateful for our foresight or curse our shortsightedness.
    Reply
  • DarrellKH
    R J Craigs said:
    It will take a long time to get to a Planet B situation. The figure of 100 years is hardly long term thinking. Cleaning up our own planet is very important but that is also short term thinking. Some planet scale disasters can only be survived by being somewhere else when they happen. We have all our eggs in one basket. We need to work on what it will take to establish a sustainable self supporting ecology and breeding population off-Earth. Our descendants, when faced with a planetary disaster will either be grateful for our foresight or curse our shortsightedness.
    Agreed. Building a self-sustaining settlement of sufficient genetic diversity on any other planet will be a daunting challenge, likely taking at a minimum a century to achieve, but there's just no getting around the possibility of a global-scale catastrophe, such as an asteroid strike, and if we fall into the trap of thinking there's no need to do it soon (because it will take so long), then we increase the risk of it destroying the only place where human life exists. There is no math and no spin that can be used to justify ignoring that.
    Reply
  • Mental Avenger
    R J Craigs said:

    It will take a long time to get to a Planet B situation. The figure of 100 years is hardly long term thinking. Cleaning up our own planet is very important but that is also short term thinking. Some planet scale disasters can only be survived by being somewhere else when they happen. We have all our eggs in one basket. We need to work on what it will take to establish a sustainable self supporting ecology and breeding population off-Earth. Our descendants, when faced with a planetary disaster will either be grateful for our foresight or curse our shortsightedness.
    We already have all the technology required to establish a viable self sustaining colony on Mars. The only thing stopping us is funding. Part of that is due to those activists who claim Space Exploration is a waste of time and demand we “fix” Earth instead.
    It would probably take 1000 years, and quadrillions of dollars, to teraform Mars to the point of living and working outside, so all colonists will necessarily have to live in habitats or underground. It is likely that Olympus Mons has thousands of miles of lava tubes where a large city could be built. Many of those who reject living underground already effectively spend most of their lives “underground” inside buildings where they work, live, play etc. in major cities.
    Reply
  • MP Illustrator
    There is an old proverb that advises: "The person saying that it cannot be done should not interrupt the person doing it."
    I am an artist so my credibility is open to question on this matter. My one claim to any kind of expertise is that, once upon a time, I illustrated a book called The Millennial Project, by Marshal Savage. It was fun, and I would like to think that I learned a lot from it. If I am allowed a brag or two, the highlight of my efforts was receiving this signed photo from Arthur C. Clarke with my illustration of a terraformed Mars hanging behind him: https://www.deviantart.com/keithspangle/art/Arthur-C-Clark-282923306 .
    Since then, I have, on occasion, returned to the possibilities of the future as a subject for my paintings, and to add depth to the artwork have given some thought to our future both here on Earth and as spacefarers. My advice: Do both. Restore the Earth and become a Space-faring Civilization.
    We have, in popular fiction, two resonant models for both goals: Lothlorien of JRR Tolkien's Lord of the Rings, and the Federation of Gene Roddenberry's Star Trek. I will leave the details to people who actually have the technical expertise to start making them a reality; my concern is more with the images of the future that I would like to see. While my work will construct no L-5 colonies or plant no trees, perhaps they can inspire others to do so...and these days we are sorely in need of positive inspiration. (Here is another link, this one to the series of paintings that I have done using the future as a subject:https://www.artstation.com/keithspangle . Never mind the "mature content" caveat...it is nothing terrible)Perhaps some of my work will trigger an idea or two.
    Oh yes...and one other thing: Get over the idea of having to confine ourselves to planets. Build L-5's, use mined out asteroids. Build ships the size of moons.
    Reply
  • MP Illustrator
    I should add this: a link to the Millennial Project: https://en.wikipedia.org/wiki/The_Millennial_Project
    Reply
  • Dandere
    Just another article about yet another intersectional waste of a university department office.

    I support environmental preservation efforts (on Earth) for practical, economic, and aesthetic reasons. But there is no imaginable scenario where Earth becomes even marginally uninhabitable through human action except the purposeful large-scale use of salted nuclear warheads.

    These creatures are just frustrated for a number of unsightly reasons, such as the perception that the rich are escaping Earth before they can be eaten, and the idea that terraforming Mars represents a refutation of the idea that Earth cannot be preserved through technology, only environmental austerity. Which it does, but nobody important cares about their pseudoscientific nightmares of total planetary collapse anyway.
    Reply