After Life on Earth

Robert directs us to an article stating several things: first, that we should save our race by colonizing outside of Earth; second, that we should avoid aliens at all costs; and finally, that we could (and therefore implying that we should) develop spacecraft to move faster than light so that we can effectively travel through time to repopulate Earth, should we destroy it.

While all of this is very interesting, my main beef lies with the first assertion, and it’s chiefly what this blog is about. I’ll touch briefly on the other two at the end, though. Go ahead and read the article. I’ll wait.

So, says Hawkings, we ought to hurry up and colonize elsewhere before we kill ourselves. Let’s look for a second at probable causes of human annihilation:

Death Option No. 1: We kill ourselves via nuclear warfare like complete idiots. I see this as our mostly likely form of death. YMMV.

Death Option No. 2: We deplete Earth’s resources or otherwise damage the planet enough that it will no longer support us, causing mass death by famine and/or plague and/or thirst and/or freezing and/or burning, et cetera.

Death Option No. 3: Cosmic accident. These happen all the time. A mega solar flare isn’t out of the question. More likely, a comet or asteroid may hit Earth. Scientists estimate that this happens three times per million years, and we’re overdue for one! This is the leading theory as to dinosaur extinction, by the way.

Death Option No. 4: Non-cosmic, Earth-related catastrophe. This may include wobbling of the axis, reversal of magnetic poles, shifting of the crust or tectonic plates that induces devastating earthquakes, melting of the polar caps that induces biblical flooding, or incurable, deadly, widespread plagues.

The way I see it, we have two methods of ensuring our continuance as a species: colonization or preservation. Both jointly would be the best way to go (IMO), but preservation of our planet is more important than colonization, because you can’t have the latter without the former. Call me a hippie if you want to, but I think we’ll be better off taking care of our planet and each other than in merely moving somewhere else. I’m getting ahead of myself though.

Of all possibilities, we have the option to save our planet by creating better energy sources, using fewer disposable goods, and educating as many people as possible on the dangers of planetary overpopulation. Is the overhaul significant? Will it be difficult? Is it unlikely to happen? I’d say yes to all of these, but that doesn’t change the truth. Earth is our natural home and the most capable of supporting us, provided we take care of it. As an ordinary American with two children, I recognize that I’m speaking hypocritically here. I know there are huge changes that would have to be made for this to work, but it would require an overhaul of our habits as a species before it could be manifested in the world.

So, colonization. In some ways, I agree with it—others, not so much. It’s true that (invoking analogy here) diversifying our stocks is a good idea of ensuring continuation of our species, but only in some respects.

For the purposes of keeping a long essay short, I’m going to assume everyone agrees that Mars is our best target for extraterrestrial colonization. If you can think of somewhere better, feel free to make your opinions at home in the comments section. ‘Kay, thanks.

Colonization of Mars would be near impossible without use of biospheres, which are far from perfect themselves. If you’ve ever seen the movie Total Recall, you have an idea of what I’m talking about. Without it, we can’t create a similar atmosphere to what we need and already have on Earth—Mars’s gravity is not strong enough. Mars also has no magnetic field, which is what protects Earth from the solar wind. In short, it keeps us from burning to a crisp, in conjunction with our atmosphere. What protects Mars, I have no idea, but Martian temperatures range from -140°F to 30°F*. Holy heck! Another thing to consider is the long-term effects of less gravity on the body. What kinds of health risks do we incur from such a weak gravity? At any rate, the Martian biosphere is our leading chance for success at extraterrestrial colonization (again, feel free to disagree in comments—I’m all for alternatives). So assuming said biosphere had no problems (like oxygen leakage), here are the main considerations for this plan:

Firstly, the people who will be populating Mars are likely to be the wealthy individuals from the wealthiest countries. Unfortunately, these people are the most wasteful, from countries that are aggressive and powerful. Those people will take their destructive, wasteful natures with them. Living in a biosphere successfully involves (are you surprised?) being careful and balanced in your use of resources within the biosphere. The ecology would be far more delicate and in need of nurturing/careful preservation than Earth. Since this is the case, why can’t we simply apply these tactics to Earth itself? I also foresee wars over Martian territory, and I don’t see that we would pose any less threat to our human brethren than we do here on Earth. Moving to Mars does not in the least reduce our chances for World War III. Therefore Death Option No. 1 is still open to us.

How do we survive on Mars? The same way we do on Earth—consumption and renewal of resources. Death Option No. 2 is tricky. I’m unsure whether the Martian soil is suitable for Earthly agriculture, but if it is, it offers a very valuable resource to us. If the water they believe may exist in a permafrost layer beneath the crust is accessible (and does exist), Mars is our lucky jackpot, because we already know it contains more than enough carbon dioxide in its atmosphere needed for plant growth. If we have neither of these, then Mars is pretty much useless except as empty space. We have to grow plants on Mars to create oxygen for us, so water and soil are necessary. If Mars has neither, we will have to export these from Earth, which is costly and pointless. We would only be shuffling our limited resources from one place to another—rearranging them, as it were. Death Option No. 2 is up for grabs as either plausible on Mars or not, but if we overpopulate on Mars as we have on Earth, the extra resources that may be available won’t last for long. Again, it would require a change in procreation habits that we’re as likely to make on Earth as on Mars.

Death Option No. 3 is complicated. Cosmic accidents can and do happen to all bodies in the solar system. Jupiter was hit by comet Shoemaker-Levy 9 only in 1994, and hit again by an unknown celestial body in June of 2009. Earth is close enough to the sun that a very large solar flare (of astronomical proportions—pun intended!) could wipe us out. Since Mars is farther from the sun, this is less likely. However, the asteroid belt lies between Mars and Jupiter. About 200 asteroid orbits are Earth-crossing and are considered potentially hazardous. Mars is logically more at risk of asteroid impact than Earth will ever be, by virtue of its proximity to the asteroid belt.

When the sun eventually reaches the end of its main sequence life, it will expand into a red giant, becoming large enough to completely engulf Earth and possibly even Mars. (And you thought the sun was big now—ha!) Even if Mars should be spared being swallowed by the sun, though, it will be too close to it for the possibility of human survival. In this respect, Mars is not better for our survival than Earth. More on that later.

Finally, there is Death Option No. 4. Each planet is different, and so obviously Earth’s potential catastrophes are characteristic only to itself. However, I’d not assume the other planets, including Mars, do not have their own potentials for armageddon.

So a few more things about colonization and human survival. I’m all for colonization as a backup plan for saving our species, but not as a way to “abandon Earth” in favor of a better place to live. We are evolved to suit the environment in which we already live. If we’re going to have to change to suit a new environment, why can’t we change to suit our current one?

If we’re going to survive against the universe, we’ll obviously have to think in very long terms. Provided a cosmic event (on either or both planets) doesn’t wipe us out, our star is guaranteed to die in about 4.5 to 5 billion years, so leaving the solar sytem is mission critical to our long-term survival. “Oh,” you say, “but in 4.5 billion years’ time we’re sure to have left the solar system!” And I can’t disagree with that conjecture. But what about leaving our galaxy, which is 100,000 light years in diameter? That means it takes light 100,000 Earth years to get from one end of our galaxy to the other! Provided we do it in time, we could manage to escape before 3 billion years have passed, when our nearest galactic neighbor, Andromeda, is scheduled to collide with the Milky Way. There’s a chance we may not even notice anything except for a slow change in stars and constellations, but an equal chance for our solar system to be completely destroyed. To avoid the fracas, we’d have to travel farther than the next closest galaxy. And I’d say, if we can do that, we can probably survive until the Big Crunch (if it will be—there are two other possibilities), when nothing—and I do mean nothing—will survive. Alternatively, if the Big Crunch is not feasible, we’ll get either billions or trillions more years, until the Big Chill wipes us out. I’m not making this stuff up. There’s a third option, though, for the fate of the universe (and ultimately our own fate), and that’s universal equilibrium. If that’s achieved, we should have no trouble surviving for eternity.

My question is, is it really worth it? Is it absolutely necessary that humans continue into eternity? I’ve never understood the need some feel to continue the species forever. I say if we survive, great, and if not? Oh, well, I was planning to die anyway. Sure, there’s something awe-inspiring in knowing we are the universe’s own consciousness—and that we are, for all intents and purposes, the part of the universe that is attempting to understand itself. Do we need to carry on forever to make that meaningful? I’d say not anymore than my eventual death makes the love I have for my children less meaningful. I’d even argue that the end of a life, either individual or species, lends it more poignancy and value—makes it more worthwhile, paradoxically speaking.

Almost done! I had just one other thought while reading the original article. (Did you forget about it in all this mess?) Does anyone else find it strange that Hawkings first warns us to abandon Earth and to avoid alient contact, and then goes on to say we should travel millions of years into the future to repopulate Earth? Waiting millions of years means we won’t know what new species may have evolved to inhabit it. Strange logic.

*For my international friends, that temperature range is -95°C to -1°C.

Sources:

Chaisson, Eric, and Steve McMillan. Astronomy: A Beginner’s Guide to the Universe. Sixth Edition. California: Pearson Addison-Wesley, 2010.

http://mytumultuousadventure.blogspot.com/2010/08/well-duh.html

http://www.foxnews.com/scitech/2010/08/09/abandon-earth-face-extinction-warns-stephen-hawking/

http://www.redcolony.com/features.php?name=whycolonizemars

http://www.ecotechnics.edu/pubs/Living%20in%20Space%20-%201996%20Strategies%20for%20Mars.pdf

http://www2.jpl.nasa.gov/sl9/

http://spiff.rit.edu/classes/phys230/lectures/star_age/star_age.html

http://outreach.atnf.csiro.au/education/senior/astrophysics/stellarevolution_mainsequence.html

http://www.galaxydynamics.org/papers/GreatMilkyWayAndromedaCollision.pdf

http://archive.ncsa.illinois.edu/Cyberia/Cosmos/CosmosFate.html

http://www.onlineconversion.com/temperature.htm