Where Will We Live After Earth?

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This article originally appeared on The Conversation.

Some climatologists argue it may be too late to reverse climate change, and it’s just a matter of time before the Earth becomes uninhabitable – if hundreds of years from now. The recent movie Interstellar raised the notion that we may one day have to escape a dying planet. As astrophysicists and avid science fiction fans, we naturally find the prospect of interstellar colonization intriguing and exciting. But is it practical, or even possible? Or is there a better solution?

Science fiction has painted a certain picture of space travel in popular culture. Drawing on stories of exploration from an age of tall ships, with a good helping of anachronisms and fantastical science, space exploration is often depicted in a romantic style: a crew of human travelers in high-tech ships wandering the galaxy, making discoveries and reporting back home. Perhaps they even find habitable words, some teeming with life (typically humans with different-colored skin), and they trade, colonize, conquer or are conquered. Pretty much, they do as humans have always done since the dawn of their time on Earth.

How closely do these ideas resemble what we may be able to achieve in the next few hundred years? The laws of physics and the principles of engineering will go a long way to helping us answer this question.

As Fast As We Can

Nature has given us a speed limit. We call it the speed of light – about 186,000 miles per second – because we first noticed this phenomenon by studying the properties of light, but it is a hard upper limit on all relative speeds. So, if it takes light one year to get somewhere, we can’t possibly get there sooner than one year.

There is also the fact that the universe is big, really big. It takes light about eight minutes to get to our sun, three years to get to the next-nearest star, 27,000 years to get to the center of our own galaxy and more than 2 million years to get to the next galaxy. The amazing thing about these distances is that, as far as the universe is concerned, this is all in the neighborhood.

Proxima Centauri is our closest star at just over four light years from Earth. (Credit: ESA/Hubble & NASA)

Proxima Centauri is our closest star at just over four light years from Earth. Credit: ESA/Hubble & NASA

The vast distances between solar systems combined with the speed-of-light limit puts severe constraints on the realities of space travel. Every space-based science fiction writer has to decide early on how to deal with this white elephant standing proudly in the room. Much of the more recent science fiction employs some form of “worm hole” or “warping space:” bending the four-dimensional structure of space and time to create shortcuts between two spatial locations in the universe.

Such possibilities have been analyzed with some mathematical rigor, and although the studies are tantalizing, they show that these methods cannot work unless we discover a form of matter that behaves very differently than anything we have ever seen.

Take It to the Limit

Practical space propulsion systems available today and for the foreseeable future are based on Newton’s laws. In order to move forward, we have to throw something backwards or get hit by something moving forward. It turns out that even using the best propulsion systems available, there is not enough mass in the entire universe to propel even a single human being up to half the speed of light. Even relative speeds of 0.01% of the speed of light start to get prohibitively expensive.

Things look slightly better with advanced propulsion concepts such as thermonuclear propulsion, but optimistic near-future designs still top out at a few percent of the speed of light.

Finding a Suitable Home

Large distances combined with low speeds means that exploration is going to take time. Astrobiologists tell us that our galaxy has no shortage of habitable worlds: estimates range from at least 1 every 10,000 stars to as many as 1 every 10 stars. Even so, given the vast distances between stars and the low speeds achievable by realistic spacecraft, you should plan on voyages between worlds taking centuries to millennia.

Consider also what is meant by a “habitable world.” To an astrobiologist, this means a planet with water oceans orbiting a sun-like star. But habitability by humans requires more than just water, and the chances that ordinary humans could simply step out and populate such a world is slim. The atmosphere and living ecosystem of Earth is the result of its own unique evolutionary history, one that is unlikely to occur coincidentally on any other planet.

Kepler-186f was the first Earth-sized planet discovered in the all-important habitable zone — a range of distance from a star where liquid water can pool on a planet's surface. (Credit: NASA)

Kepler-186f was the first Earth-sized planet discovered in the habitable zone. Credit: NASA

Despite its current problems, the Earth is still far closer to the ideal that our species grew up in than any world we are likely to discover out in the galaxy. Climatologists warn us of the devastation that could result from increasing the carbon dioxide in our atmosphere by less than a tenth of a percent. Compared to that, another living world, with its own unique ecology, would most likely have an environment that is unbreathable and infertile at best, lethally toxic at worst.

Terraforming, or modifying such a world to be habitable to humans, would require reconstructing its atmosphere and biosphere practically from scratch, eradicating any native ecosystem. This would be a task orders of magnitude more challenging than the relatively minor tweaks needed to restore the Earth’s environment to a pristine state.

Spaceship Home

Perhaps a more fundamental question, then, is why humans would wish to colonize other worlds. Given the centuries-long treks between stars, interstellar voyagers would necessarily have moved beyond the need for a planet to support their lifestyle: their vessels would be their habitat, autonomous and self-sufficient. They would not have to seek out new homes, they would build them.

From an economic standpoint, this would be vastly more resource-efficient than converting entire planets. NASA-sponsored researchers have developed detailed plans for spinning habitats that could accommodate tens or hundreds of thousands of inhabitants, from material that could be mined on site from an asteroid a few hundred meters across. This type of construction would avoid one of the major expenses of space colonization: the cost of lifting millions of tons of building materials into space.

Since our Solar system contains millions of such asteroids, they could support a population many times that of Earth, in air-conditioned comfort, with a fraction of the effort and none of the exotic technologies envisioned to terraform Mars, for example.

Do We Need to Visit the Stars?

Ultimately, travel to other stars and colonization of other planets will be driven not by need, but by desire: the intellectual impulse to explore strange new worlds, and perhaps an aesthetic preference for “natural” (albeit engineered) environments.

Where do we go now? The commercialization of space flight promises to bring the cost of space travel down considerably, from tens of thousands of dollars per kilogram to just hundreds of dollars per kilogram, through economies of scale and reusable rockets. This means that space will be more accessible to more and more people.

NASA studied the asteroid Eros up close more than a decade ago. Asteroids could supply the needed resources to build orbiting communities. (Credit: NASA)

NASA studied the asteroid Eros up close more than a decade ago. Credit: NASA

Already the lure of asteroid resources has fueled commercial competition. A single kilometer-sized metallic asteroid could supply hundreds of times the total known worldwide reserves of nickel, gold and other valuable metals. Space-based solar power could provide limitless renewable energy – once the cost of construction in space becomes manageable.

The hyper-exponential growth that we have seen in other areas like automobiles and computers can now take place for space technology. The physical realities described above paint a very clear picture of the near future: orbital habitats perfectly designed for our lifestyle using resources obtained from our sun, Earth, and the asteroids.

So if Earth ever become uninhabitable, we won’t need to traverse the stars to find a new home. Orbital habitats will require a significant expansion of space industry, but this will happen soon enough, especially if we are forced to leave the planet for a little while so it can recover from our mistreatment.

Of course, if we discover warp drive, the picture will be entirely different.

 
The Conversation
Top image by iurii/Shutterstock

CATEGORIZED UNDER: Space & Physics, Top Posts
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  • lump1

    Our CO2 emissions are making the Earth a worse place to live, but there is no chance that we can make it uninhabitable, not if we dig up and burn all the fossil fuels of the whole planet. Doing this would increase the average temperatures by 5-6 degrees. It would be nasty and disruptive, but please don’t ever call that “uninhabitable”, especially if you go on to talk about places in space where we might prefer to live.

    No matter what we do to the Earth – global warming, nuclear war, biowarfare, Nickleback, asteroid impact, ozone depletion, etc. – it will remain by far the most comfortable place in the known universe for biological humans to live. At worst, we will need to filter our breathing air and wear special protective clothing when going outside. That would be bad, but a trifle in comparison to the challenges of living on Mars, a radiation-soaked planet without a magnetic field, intolerable temperatures, insufficient gravity and inadequate solar irradiation. Yet Mars is always mentioned as the default life raft, as if living there could *ever* be easier than living on Earth. If we’re ever faced with existential danger, we should escape to quarantined underground and undersea shelters, where we are much more likely to wait out the troubles than on Mars. I challenge anyone to describe for me a near-term (next 10 million years) scenario in which the Earth could become more uninhabitable than Mars is. Use your most pessimistic imagination, please.

    • facefault

      I challenge anyone to describe for me a near-term (next 10 million
      years) scenario in which the Earth could become more uninhabitable than
      Mars is. Use your most pessimistic imagination, please.

      Excellent comment! Here are the most cartoonishly awful challenges I can come up with.

      1. A rogue planet or similar big dumb object passes by and disrupts Earth’s orbit such that within 10 million years Mars will be a more pleasant temperature than Earth is.

      2. We get very good at making synthetic hydrocarbons, and completely fail at geoengineering. Perhaps sulfate aerosols have some horrible property we didn’t anticipate, or misguided politicians are convinced it would make the environment even worse.

      Wet-bulb temperatures exceed 31 degrees (
      http://www.pnas.org/content/107/21/9552.full ) over enough of the Earth’s volume that building habitats on Mars’s surface is more practical than trying to build deep enough underground or underwater to escape the heat.

      3) A cackling madman builds a bunch of cobalt bombs. His futuristic mastery of meteorology lets him work out how to get the fallout distributed evenly worldwide. Few people make it far enough underwater or underground to escape the radiation, because *handwave*

      4) Gamma-ray burst that hits Earth but misses Mars.

      • Eric Lipps

        How about this one? We burn enough hydrocarbons to trigger a positive feedback loop in which more greenhouse gases are released into the atmosphere, further raising the temperature and causing more greenhouse gases to be released from various sources, round and round until we end with a somewhat cooler Venus–say, only hot enough to boil water, rather than to melt lead.

        That scenario is considered unlikely but not impossible by serious researchers.

        • facefault

          Oh yes, the clathrate gun hypothesis is a scary one.

    • Hellfire LWD

      Ok…

      Nearby supernovae… Gammaray bursts… rogue planets… rogue (neutron)stars… rogue black holes etc.
      big asteroids or comets… our Sun having unexpected behavior… solar flares and cme’s.
      Earths magnetosphere failing….

      I do agree with your point of Mars being a dumb alternative… its really no solution and i always felt this way… Mars didnt die out for no reason.

      But i still feel interstellar travel will be very likely to be reality… surely in the timescale you described. In that time… i have no doubts if any humans still live… they will be able to travel to the stars in short times. They will also have found suitable starsystems with habitable planets.
      Just to be clear… if humans survive long enough… they would have to leave Earth… theres no other way….
      Think of these natural disasters from space… and dont forget about the lifespan of our star… the sun is middleaged now… it will die and earth will die with it. Now this will take at least a few billion years… but like i said… if humans survive this far… then there is just no other way than packing up and leaving.

      • lump1

        Notice that not a single thing on your list is a case where Earth becomes less inhabitable than Mars is.

        Yeah, I agree that humans should send out interstellar colonies, once we master artificial wombs, automated resource harvesting, parenting AI and other technologies that would allow humans to get a foothold. I’m just saying that in our own solar system, off-Earth colonies will not protect us from extinction. I like your list of potential catastrophes, but Earth will be the safest place in the solar system to be if these things happen.

        • Hellfire LWD

          Well… i agree with you that mars will never be a better place to be then Earth itself is. Assuming something bad would not happen to earth alone.

          But… the stuff i listed will do make earth and the entire solar system unhabitable. If a rogue neutron star enters our solarsystem… there will be no planets or any other spot safe… in our solar system.
          We will have to move if this happens… one way or another… it will be… moving or dying at this point.

          When our host star dies… Earth will die with it… and so is everything else in our solar system… This is also an event you want to survive by not being around when it happens.

          Just to be clear… Mars is no answer. I never felt like mars is an option… it didnt die out for no reason.

    • Jordan Tampa

      Are we gonna ignore the fact that this is all nicklebacks fault?

  • Brett Petracek

    Well it was +2c today where I live in Canada and everybody seems to be a lot happier than this time last year (-30c). The year before last it was probably -10c next year might be -30 again, or +10. Whatever happens humans adapt, if/when it becomes economically feasible to completely switch from fossil fuels, or create technology (or expand existing technology) to scrub the air “clean” then it will happen because it is the right time to do so. The way I see it: there are ~7 billion people on the earth now. 2050 is projected to have over 10 billion (and Canada probably will still have less than 100 million). It won’t be climate change that will ever affect human growth, it will be overpopulation itself that determines when we search for other planets.

  • meerkat

    I think we will all go extinct. End of story.

    • s3rl0ck

      Really nip it in the bud, huh? Despite the bluntness, I agree with your statement.

    • Jacob Lively

      Depends on if our rate of technological advancement can exceed the rate at which the outdated technologies of past generations like fossil fuels and nuclear bombs can destroy us.

      • meerkat

        Maybe, we will survive a long time from now. I don’t think we will go to space though since there are many factors that just make it a place that is not very suitable for human life, all the cosmic rays,possible biological hazards and such. Astronauts get many health problems being in space too.

        But whatever happens I’m sure we will eventually go extinct once the resources run out or the earth becomes unusable for us even before the earth reaches it expiry date we will die out. But who knows maybe we will be able to find a solution perhaps we will find a way to live in the ocean…lol

        • Jacob Lively

          It’s important to note that those things you mentioned are known as engineering problems.

          The only thing to be concerned about is whether or not something is physically impossible or not. There are only two technologies I know of that are physically impossible – Perpetual Motion Machines and Precognition.

          Resources on earth are not running out, but we are burning through some of them at an incredible rate (fossil fuels). Solar power isn’t going away anytime soon, nor is wind or hydropower. There’s a very real chance we’ll have fusion by the end of this decade and it may be commercially available by 2030. Once that happens, our resources are essentially limitless.

          • meerkat

            Solar power, wind power and hydro power require resources to begin with to harness and at the moment they are not as efficient as many other sources of energy sure maybe we will be able to start using these kinds of “energies” more but with population increasing I think energy demand will just go up.

          • Jacob Lively

            Yes, energy demand is going up, as is population. Though population is, I think, starting to level out as contraceptives, abortion and birth control in general becomes more available worldwide.

            Yes, solar, wind and hydropower require resources, but I really don’t see us “mining out” the wind any time soon, like we might with a coal or uranium mine. Because of this, these are more sustainable.

            And yes, solar, wind and hydropower are not as efficient as the wonderful natural battery known as “fossil fuels.” It’s up to us to devise a more efficient, more sustainable method of acquiring energy.

    • Brian Allan

      Easter Island would be a good example for your theory…

  • Citizen

    This has been clearly predicted in the scriptures of Hinduism. The lifespan of the world divided into 4 yugas. We are living in the last sector Kali Yuga of which the Godess Kaali the Godess of destruction rules. The signs are ominous. The end of the world or Pralayas have happened before according to vedic sayings.

  • Vander

    Lump1 – Here’s an idea.. What if, with climate change, comes social change. Mankind turns on itself, rather than becoming braver and more willing to cooperate. Mutual destruction is a darn sight easier than mutual construction. Climate change is the start, its when we start using nuclear war to secure dwindling resources and maintain important infrastructure. The planet won’t kill us, we will kill us, like we’ve always done.

    Every thing that happens on this planet has a ripple effect. No incidents are ever isolated. Please consider your challenge met.

    I do hope you enjoy my most pessimistic imagination.

  • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

    Of course, if we discover warp drive, the picture will be entirely different.

    1) Make a wormhole.
    2) Put its entry below its exit in a steep gravitational potential.
    3) Place an open solenoid with its long axis parallel to the drop path and surrounding it.
    4) Drop in a magnet.
    5) Wait a while, local time.
    6) Connect the electrical load across the solenoid.
    7) If you want physical travel, drop in your spaceship. Wait a while, local time. Pull out the bottom entry. Zoom!

    But what of the First Law of Thermodynamics – “you cannot win”? No problem! Conservation of mass-energy arises from Noether’s theorems and the spatial homogeneity of time. Time passes at different rates for different heights in a gravitational potential. Nothing is violated.

    This may not be implemented until all unknown hazards are enumerated. Managerial studies must be funded before study studies are studied.

  • David Jennings

    If we could go to the trouble & expense of relocating to orbital habitats, we could build arcologies or subterranian cities a lot easier & faster.

    • RedWell

      Exactly. I’m a fan of human expansion, but the scenario in which humans would need to leave Earth due to a ruined atmosphere is lazy. In addition to the benefits you mention on Earth, humans would enjoy access to water, their own gravity, access to preexisting human infrastructure, a protective magnetic field, a knowledge of Earth’s resources, and, yes, an atmosphere, even if we couldn’t breathe it.

      Of course, the article is really about how to build a humanity beyond Earth. Still, a more plausible scenario is that some body or phenomenon is going to destroy or utterly ravage the Earth itself.

  • Dan Alvírez

    This article doesn’t even touch on the fact that our biological systems have evolved to live on this planet. It is nearly impossible to reproduce in a weightless environment. Experiments with rats in space show that a fetus cannot develop normally in weightlessness. We are meant to live here, just like life elsewhere is meant to live wherever it is. We’re not meant to go anywhere else.

    • Adam

      If we had artificial gravity via a rotating station we could simulate Earth’s gravity in space. Problem solved.

  • Joel Novatne

    We don’t have to reach a planet outside our solar system to start with. We are perfectly located to start exploring our solar system.
    We have a moon to start with learning space travel
    We have Mercury, Venus, and Mars to continue learning with for various purposes.
    We have an asteroid belt with at least one dwarf planet (Ceres) and is full of raw materials to use to go farther.
    The gas giants have many moons we can colonize. The gas giants themselves are resources for fuel and other needs. These will come in handy too when the Sun starts to expand.
    Beyond that is the Kuiper belt and the Oort cloud which can provide us with what need to go interstellar.
    The Oort cloud gets us 1/4 of the way to Alpha Centauri and by the time we are in the Oort cloud I am sure those distances won’t be as daunting as they seem now

    • zlop

      “We don’t have to reach a planet outside our solar system”

      It would take thousands of years to reach the nearest star. However, in a few decades, we could deploy an array of satellites, used as a synthetic array radio telescope, to image planets in nearby solar systems.

      • Eric Lipps

        This assumes we not only can’t beat the light speed limit but can’t amble along in space much faster than present-day rockets do.

        If we could get to ten percent of light speed, Alpha Centauri would be forty-odd years away (assuming we reached that speed in a short time rather tan only at midpoint). At a constant acceleration of 1.0 g’s, it would take only five weeks to reach that speed. Even at 0.1 g’s, it could be done in under a year. (Do the math.) We can’t do it now, but a hundred years ago we couldn’t reach the moon, or even Earth orbit.

        A starship could be built as essentially a traveling O’Neill colony and could reach many nearby stars in under a century, not thousands of years. It might be harder to find enough people willing to sever themselves from humanity by such distances yet psychologically healthy enough not to destroy themselves.

        • zlop

          “(Do the math)” — Math is not real

          “We can’t do it now, but a hundred years ago we
          couldn’t reach the moon, or even Earth orbit.”
          “Dark Side of the Moon: Stanley Kubrick
          and the Fake Moon Landings”

          Perhaps, 50 kilometers/second is plausible,
          allowing time to deal with meteors in the way

        • MeanOldMan

          Actually, we would have to be able to do much better than 10%c to reach Alpha Centauri in 40 years. You would spend the first half of the trip speeding up, and the second half slowing down so you wouldn’t blow right past AC.

    • Eric Lipps

      We will never, ever, ever be able to solve our population problem by exporting it, at anything like present levels of population growth. Where are you going to put ninety million people a year? How are you going to put them there along with everything they’d need to survive?

      Like it or not, we’re going to have to stabilize the global population. Maybe a few thousands, or a few tens of thousands, of people per year might someday be able to emigrate into space, but don’t count on more than that.

      • lump1

        It turns out that we don’t need anything as fancy as colonizing other planets. Apparently, schools that admit girls cause fertility rates to fall through the floor. We might actually be alive when the population of humans in the universe hits its peak. We are arguably already past Peak Caucasian: there will never be a larger number of white people than there is now. Estimates for Peak Human vary, but it could happen as soon as 2075, and I plan to be very much alive for it.

  • zlop

    Space colonies made from Moon materials, robots to build an outpost on Mars, solar shields to cool Venus. There is a lot of water on Earth, to make rocket fuel from, Solar powered satellites to beam power within the Solar system . .. …

    However, the Oligarchs want to enhance their dominance, Carbon Tax, Agenda 21 and Georgia Guidestone almost everyone.

    • jimbow

      Like wise there is allot of rocket fuel in Jupiter and its moon, and the other outer planets.
      If humans were ever decide to go to the stars, they may be able with the outer moons to push one of them out of obit, and speed that moon of the up with the muti-generation ship or ships to use it as a fuel source for those ships. We can’t do now but it might be done many generation from now.

      • zlop

        For the next century or two, just looking,
        deploying probes and synthetic array telescopes.
        =======================================
        Looking at an Alien near Alpha Centauri,
        Using Solar System size radio telescope at 100 GHZ

        distance to Alpha 4.35*9.461 * 10^15 meters
        λ = 0.003 meters (100 GHZ)
        distance to Pluto 5.9*10^12 meters

        r/( 4.358*9.461 * 10^15) =1.22* 0.003/(2* 5.9*10^12)
        Resolution of 12.8 meters, cannot see the Alien

        If a near IR array is possible λ = 10^-6 meters
        r/( 4.358*9.461 * 10^15) =1.22* (10-6)/(2* 5.9*10^12)
        Resolution = 0.0043 meters

        • jimbow

          interesting idea

          • zlop

            There are low noise amplifiers available. Deploy 3 satellites, aim at a star,
            beam the amplified signal to a central processing/combining point.

  • nik

    Not another misguided person who swallows the misinformation/propaganda, that human generated CO2 is the cause of global warming.

    The idea for ‘space stations’ orbiting the sun, is not new, but to make them radiation proof for long term habitation and survival would be a major challenge.

    In theory, there could be any number of stations set up in the same orbit as earth, but making them totally self sufficient has so far eluded all attempts.

  • Overburdened_Planet

    From 2008:
    After reading how the Space Station needs plumbing, I wrote this:
    Stephen Hawking tells the world we must explore other worlds because we’ll destroy this one. Hmmm, let’s see, both Biospheres failed, and now we have to fix the Space Station shitter? Can you imagine how dependent we will continue to be on this planet when attempting to colonize elsewhere?

    Too much money is spent on wasteful programs when we should be trying to solve our current problems. Put another way, why waste all the resources and effort colonizing space when if we can’t fix our problems here, how will we avoid these same socio-political problems on other planets? Wouldn’t we be just as likely to destroy ourselves on other worlds as Hawking claims we’ll do here?

    And to those who say exploration is who we are, don’t forget how exploring leads to conquering. Will you be on the winning side, or be on that spaceship? Who really thinks they’ll qualify for access to limited seats heading for other worlds? Most of us are worthless to the powers that be, and the people in charge are interested because they know they’ll be on those ships…if it happens in their lifetime. As to you and me, we’ll be left here, or shipped off world to be someone’s slave.

  • John F Remillard

    Evolution is a process of nature that continually arranges molecules into different configurations. Humans are just one set of molecular configurations that happens to be sustainable in the environment on earth that has existed for about 3.8 billion years.

    Throughout the entire universe molecular configurations are in states of changes that have been occurring since time began. It is a good chance the processes of reconfiguring molecules into new structures is going to continue until the end of time.

    The work of making new molecular configurations being done by humans is a scaled-up version of the same work being done by nature. Humans are constantly creating molecular configurations that are either clones or new molecular configurations.

    The human molecular configuration set seems to be evolving in the direction of developing the capability to make new molecular configuration sets of human life forms that would be able to survive in radically different environments than the very narrow range found on planet earth (oxygen, moderate temperature, gravity, magnetism, water, etc.).

    I attended a scientific Transhumanist conference in Salt Lake City last year where I witnessed several visiting Mormon Ministers speaking about how the move toward manufacturing synthetic humans conforms to GOD saying the goal & destiny of humans is to become immortal just like GOD.

    As a biologist & computer programmer I can say that humans are very close to building the capability of transferring (uploading & downloading) the essence of a human (mind, spirit, knowledge, memories, skills, abilities, feelings, personalities, thoughts, values, and imaginations) to microchips.

    Microchips containing the essence of humans can be inserted into robotic bodies that can survive space travel as well as or better than the Voyager probes have been surviving space travel since the 1970’s.

    • Brian Allan

      Why not simply “evolve” to our ultimate form, a cyborg or completely robotic entity, i.e.: homo roboticus? This would remove limitations on space travel and probably allow us to exist in a totally destroyed Earth environment.

      Abandon the delicate organic body and move on…

    • zlop

      Universe has a tendency towards development, not Entropy Death.
      Second Law violation enables development.
      Blind watchmaker, Random Darwin, cannot make anything.

  • Brian Allan

    “Pretty much, they do as humans have always done since the dawn of their time on Earth.” And based this one would hope humans evolve to something less destructive before they venture forth into the cosmos…

    • zlop

      Before they consume the Universe, Carbon Fool-Prints have
      to be destroyed. Support the Carbon Tax Extortion Racket.

    • Verystrange333

      It is so nice and comfy to be a baby. It is also so safe to be a child. To be home, with your parents, in your cozy bedroom, where nothing bad could happen. Well, there may be a fight with a neighbor kid, or may be a fight with your mom… But when you calm down, you just go to bed, your windows opened… the aroma of the warm summer night fills your bedroom, and the trees outside gently rock their branches, as if they are singing you a lullaby…

      And then you are a grown-up. You are not in your parent’s home, not in your bedroom anymore. Your mom is not around. May be you are in a dorm with a view on a dump… Wait. But why are you smiling? Because you are finally an adult! Even if you are still a “young adult”, nevertheless, you have overgrown your cozy but dependent life, you are on your own, and the wonderful world is open for you.

      Aren’t we all? Aren’t humans finally ready to grow up? Grow up and leave our beautiful, cozy, but also so old and so boring home for a new life, new freedom, new discoveries, new adventures, and new opportunities? We can do so much. The universe is open and waiting for us, young adults, to explore its wonders. People: it is time to leave our old planet. Seriously. Just consider it and start working.

  • http://bmeupteleport.com Bmeup Teleport

    First the speed of light is not the limit to transportation, yes it is true using current physics, but entanglement beats that speed hands down. There are two ways to reduce population, offshore people (colonize other planets) or just kill them all off with wars.
    Forget about climate change, there is possibly something entirely outside our control causing this besides our unruly governance of our planet. It would possibly take care of the population problem too. We, those that survive go back to just basic survival skills.
    We could create teleportation of objects and humans also. Distance and time in travel would be reduced to almost instantaneously. We could go anywhere (almost) surely we could find some nice habitat to takeover by force. The problem is, that place will be getting the same demise earth is scheduled to received, We would have to leave this universe entirely.
    But even so, we still should develop teleportation, it would be a nice tool to have in our toolbox no matter what happens.

  • Tariq Mehdi

    No human will ever set foot on anything but earth again. Stephen Hawking once said in 500 years Mars will have its own language and currency, but we are unlikely to ever even go to the moon again, much less Mars or any place beyond.I greatly respect Stephen Hawking’s knowledge, but on that one I think he’s wrong. I heard it would take at least 10 years to put a man on the moon again and the cost is greater than what NASAs budget could afford. Economic reality and the limits of physics will ensure mankind remains in its proper place, planet Earth.

  • zlop

    Mars outpost, living in deep valleys and caves, is easiest.
    Other places, would be difficult to make self-sustainable.

  • Jerry Campbell

    There is one type of space station that I believe would be ideal for launching lunar, Mars (or further) missions or interstellar space travel: a station suspended at the L1 point between the moon and Earth. A tether from the moon would ensure that the station remained in place, but would not have to support much weight (force) as at that point the gravity from the Earth and Moon cancel each other out. The tether can remain in one place on the Moon as only one face ever faces Earth. This would also allow material to be brought up from the Moon’s surface cheaply, by climbing the tether rather than depending on rocketry. I am quite surprised that no such proposal has ever been studied, as once built this station would be perfect for launching far-ranging missions to anywhere.

  • MeanOldMan

    Ponder this:
    Our additions of hydrocarbons and other ozone killing, heat trapping molecules into the atmosphere is producing a feedback loop that far exceeds your seemingly meager imaginations.

    Warming the atmosphere reduces global ice coverage. Land and ocean absorb much more energy than ice. More energy in the form of light is reflected back into space by ice than by land or ocean, which absorb it and… wait for it… warm.

    Ocean currents depend upon the balance of temperature differences from equator to pole, and bring nutrient rich water to higher latitudes. If that doesn’t happen, the ocean becomes less ‘energetic’ even as it warms.

    Warm ocean releases more of the frozen methane sequestered on and beneath the ocean floors, adding more warming chemicals to the atmosphere. It warms more, the ocean warms more and releases more frozen methane. Uncounted millions of years (or even just 6,000 years, if you’re a fundamentalist) of decayed and decaying biomass await like C’thulu beneath the waves, waiting for more to be released so more can be released.

    Carbon dioxide acidifies the oceans. The acidification of the ocean kills off the very life we depend upon to oxygenate the atmosphere. With approximately 2/3 of the available oxygen in the atmosphere gone, and carbon dioxide and methane in the mix, it would get very nasty very quickly.

    Add to that the storms and unstable weather that more energy will cause (you think you’ve seen superstorms now? Imagine something the relative size and ferocity of Jupiter’s GRS) and live quickly goes downhill. Look up “runaway greenhouse effect”. And look at the stats on our closest planet, Venus.

    We’ve proven in the past hundred and fifty years that we ain’t all that bright. Quit proving the point.

  • Arthur Collins

    We are likely to become a space faring species sooner than most realize. The threshold of the speed of light is something different than conventionally imagined. The Speed of Light is really only the expansion rate of Space/Time itself. Once we get our heads around that fact, we will find that it becomes possible to sidestep the distance factor by producing a temporal event that forces a conflict in relativistic time between where we are and where we want to be. The readjustment of that temporal distortion that allows both to exist in this timeline will result in the instantaneous travel between those two events.

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