io9 already planning to colonize gliese 581g…
Ads for extrasolar attractions and preemptively naming cities on an alien world are all well and good. But what will it take to really start colonizing a distant planet?
Recently, planet hunters found the third planet thought to be potentially habitable, and io9 is already asking their resident physicist to calculate how much time, energy, and fuel it would take to travel 20.5 light years to the new world it’s discoverer named Zarmina, after his wife (brief answer: a lot), thinking about what cities could be built on its surface, and what their colonization museum will feature. If only the people who make spacecraft and put together space exploration plans were that excited, we might see interstellar travel by the end of the century, or in the early 2100s. But before we start building antimatter or black hole driven craft and blast off on a roughly 120.5 trillion mile journey, there are a few things to consider about traveling somewhere so far away, to a planet we know pretty much nothing about in the grand scheme of things. If we’re ever going to be a truly space-faring species exploring the cosmos, we’re going to need to start thinking like one first.
1. We need a good idea of where we’re going. Again, at first glance, this is pretty obvious. However, we don’t have telescopes powerful enough to get a picture of 581g and determine whether it’s like Earth, or closer to a runaway greenhouse world like Venus. Keep in mind that in our solar system, Venus is also in the so-called habitable zone, and yet the idea of Venusians exists as hopeful speculation about floating microbes. So just because 581g floats in the habitable zone doesn’t mean anything other than its distance from its parent star, and whether it’s tidally locked in its orbit or not. Since, from my understanding, 581g doesn’t transit its sun, we won’t be able to get any spectroscopy readings either, and we can’t exactly swing our solar system around to get in a different position and take a better look. But that said, let us not forget that Gliese 581 also offers two other worlds on the edge of the habitable zone, 581c and 581d. With three worlds which have a potential for life in one solar system, it may be worth the risk to boldly plow ahead with the trip and explore this rare chance to thoroughly explore three extrasolar habitats in one fell swoop.
2. We need new propulsion systems. This is another obvious point, but what’s not obvious is what to use for an interstellar spacecraft. Antimatter is very risky, expensive, and dangerous, and would be an additive to an already vast amount of propellant at best. According to io9’s calculations, it would take 530 times the mass of a spacecraft in fuel to get to Gliese 581. So if you launch a decently sized 1,000 ton base/ship, be ready to fill it with more than half a million tons of rocket fuel and you’d need to put out 4.77 × 10²⁵ J to accelerate that craft to nearly the speed of light and make the trip in less than three decades. Obviously, launching enough rocket fuel into orbit simply wouldn’t work since the heaviest thing in orbit right now is the ISS at 370 metric tons, and we had to put it together piece by piece. So no rocket fuel, no antimatter, what do we use? Well how about the miniature black holes mentioned above? You could compress nearly enough energy to make the trip on terra firma and lock it away into an object roughly the size of a proton that could be moved by a conventional rocket equipped with powerful electromagnets to make sure it doesn’t just drift through the hull at takeoff.
Sounds crazy at first, but hey, we’re trying to cover space at nearly the speed of light. Might as well go all out in the process and lock up an oil tanker’s worth of rocket fuel with lasers and feed it so it gives off energy? Sure, the black hole will actually be stable for years on end, but because of its small size, it will regurgitate far more energy than it absorbs. It takes a while for something far less than an angstrom across to swallow anything of significance, and if the heat, light, and radiation are absorbed and channeled out of the spacecraft’s exhaust, the astronauts will be rocketing by at almost 95% the speed of light in about a year. Of course, now we’d need to figure out how to protect them from interstellar debris that would sandblast the craft into vapor at relativistic speeds, so perhaps some sort of electromagnetic force field may be in order since no material would be able to handle that much stress for more than a few hours, much less decades of wear and tear.
3. We need to go from ship to base on landing. Coming to another planet means that everything you need to use on its surface should be right there with you. One easy way to make sure that you already have a place to stay on an alien world could be to build your ship to turn into a modular base on landing. This way, as you’re slowing down and positioning yourself to land, you can detach parts and pieces of your craft, arrange them for a group landing in close proximity to each other, then connect the modules together into a base. Your engines become your generators, your armor and electromagnetic shield will protect you from the alien elements, and your living quarters… Well, they’ll just have to stay your living quarters. Not much we could really do there. With multiple missions to the same world using interchangeable, modular craft, an entire city can quickly pop up in an alien wilderness. Just make sure to pick a nice, flat place to land, and to have the ability to take off and land in better spots if your first landing doesn’t go as smoothly as you hoped.
4. We need to come in peace, and armed and dangerous. Now, this may seem like a contradiction, but think about the following. We want to explore habitable worlds because there could be life there. And if there’s alien life where we’re going, especially places where we hope there’s intelligent life, there may be something like a military in orbit when we show up on the aliens’ radar. As peaceful as our intentions may be, they don’t know who or what we are, or why we’re there, so they may well shoot first and ask questions later. We need to have an effective plan for surviving an orbital dogfight and pack KKVs (kinetic kill vehicles), and nuclear weapons to generate electromagnetic pulses that’ll fry anything using electricity while irradiating our attackers. Again, the hope is that a more or less curious alien species won’t try to kill us the instant we show up, and that we never have to use a small arsenal to defend ourselves. But on an alien world, anything can happen and we need to be able to protect ourselves should the need arise. And that applies to any feral animals that’d try to attack our bases on exoplanets as well. Intelligence and hostility usually don’t correlate, as far as we’re aware.