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Research Suggests How Alien Life Could Spread Across the Galaxy
astroengine writes: As astronomical techniques become more advanced, a team of astrophysicists think they will be able to not only detect the signatures of alien life in exoplanetary atmospheres, but also track its relentless spread throughout the galaxy. The research, headed by Henry Lin of the Harvard-Smithsonian Center for Astrophysics (CfA), assumes that this feat may be possible in a generation or so and that the hypothesis of panspermia may act as the delivery system for alien biology to hop from one star system to another.
Habital planets are so rare and far apart that alien life wouldn't be able to spread across the galaxy. Hell, even earth is so far away from the nearest possibly habitable planet that if we could travel 90% of the speed of light, it would take something like 10,000 years to get there. Much less a population and equipment and supplies enough to start a society.
Actually, we don't know if habitable planets are rare. We are finding a bunch and have barely look at what the universe holds. Now the traveling thing could be a problem, but maybe there are civilization on other planets that don't waste their time and resources killing each other and actually focus on science and space.
Be seeing you...
Hell, even earth is so far away from the nearest possibly habitable planet that if we could travel 90% of the speed of light, it would take something like 10,000 years to get there.
Spores are patient.
It seems likely that mankind, and aliens who got started before us, will eventually establish permanent residences off of their home planets. In the not-so-distant future, the majority of mankind, by percentage, will live off-Earth. However, you should think of the planets as being the bottom of very deep holes, with most of them being too hot, cold, poisonous, exposed to radiation, or too much or too little pressure. The task of getting and leaving these places is risky and expensive, too. Let's just give up on the idea of colonizing Mars for the forseeable future, please! It may not always be so, but the solar system's orbital rocks are easier resources to get, and spitting up material from low-gravity objects with mass drivers. There's no point to terraforming a planet when that will take thousands of years, and no human civillization can keep a project like that, and it's cash flow, going for so long.
In short, we're just not gonna live like pale, stick-figure trolls in underground caverns on the moon or mars. Mining will be done by pulling a big bag over an asteroid and breaking it up from the outside in. Attached refining equipment will separate useful elements and chemicals. This will be mostly-automated. We'll use the tailings as concrete to build our colonies. A gigantic mirror will heat the crushed rock and sinter it into shape, like an enormous 3d printer. There is enough material to build millions of them in OUR OWN solar system, and they'll be essentially self-sustaining once they've been established. Conditions inside will be perfect for human life. It's a far better prospect than making do with low-gravity moons and poisonous planetary atmospheres. Groups of colonies might form "countries" and others will operate independently. The colonies will be built robotically, so the cost will eventually drop to the point where one might be owned by a single family or other social group.
While most colonies will participate in a humanity-wide economic and social network, a life of physical isolation and self-sufficiency will be the norm for most. We'll be in communication, but not often physically visiting other colonies. Some of these may try hurtling themselves onward to the next closest star. They'll stay in touch the whole time, they'll just be permanently out of reach from then on.
The stars DO NOT need to be sun-like, nor do they need Earth-like worlds! They just need to have exploitable resources in easy reach. Red and brown dwarfs are more plentiful than any other type, and they'll last orders of magnitude longer, too. This is probably where the majority of intelligent life will live at some point. Not to miss out on any exploitable resource, those who live around dwarf stars will push onward to practically every type of star within reach. A million years or so, and we'll have colonies throughout the galaxy, and hundreds of alien neighbors to enrich our culture and science.
Now the traveling thing could be a problem, but maybe there are civilization on other planets that don't waste their time and resources killing each other and actually focus on science and space.
This. There's 7 billion of us. I'd wager less than 100 million of us are engaged in productive activities besides life-sustention, probably less than 10 million using their immense brain computation ability to do it. But this is due to war and inequality, not that the rest of the world are idiots. Not that they were born idiots. Some may have been brainwashed so thoroughly that they might as well be idiots, but that's still not necessarily a permenant condition. If everyone was given equal opportunity, and people with brilliant ideas didn't have to struggle just to survive, the average citizen struggle just not to die from all the corporate poisoning etc, then something closer to 4-5 billion of us could be doing productive stuff. Amazingly productive stuff. Stuff that probably less than 10000 people alive today could even imagine under current society.
There's something I've never figured out about this particular theory. All life, even some sort of "patient zero" alien life, had to arise from non-organic substances somewhere, right? If it can happen once, then it should be able to happen any number of times given a set of similar conditions. Given the size of the universe, and even our own galaxy, that's like to be a *lot* of places.
As such, why would anyone think it's more plausible for a chunk of life to hitch a ride on some piece of space debris, and then survive re-entry on a coincidentally habitable planet on which it can flourish... than for life to have sprung into existence here, where obviously conditions were optimal for it (or at least life as we know it)?
I have to wonder if the enthusiasm for this theory is partially based on the admittedly exciting prospect that we could be the descendants of exotic alien lifeforms rather than some homegrown slime mold.
Irony: Agile development has too much intertia to be abandoned now.
Hate to break it you, but the formation of the Moon probably didn't seed the solar system (or anywhere else) with life from Earth. The earliest single cell life forms likely date to around 3.6 billion years ago; the Theia impact hypothesis puts the collision around 4.4 to 4.5 billion years ago (and only 30-50 million years after the Solar System even began forming). Even if both estimates are off by a couple hundred million years, there is still no overlap. Earth was an uninhabitable ball of molten rock at the time, not remotely suitable for the initial development of life remotely like ours.
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