Saturday, September 8, 2012

Generation Ships

Warning: this post gets strange and creepy. Read your own risk

One of the great staples of science-fiction is human settlement of space. The protagonists are shown plying the cosmos in gleaming ships capable of conveniently violating the speed of light to have adventures on fantastic worlds far from our own. The unobtanium powered handwavium drives permit the ships to cross the incomprehensibly great vastness of space in a matter of plot moving months, days, or hours. This allows us to have homes on many worlds, and importantly, to travel between them. This is not possible by any method we are even close to understanding.

Space is big. I mean really, really big. Metaphors break down and the mind boggles with the sheer size of it all. The Voyager 1 space probe is traveling at 62,136kph (38,592mph) and was launched way back in 1977 and is only now at the edge of the solar system. That is only 11 billion miles away. If Voyager was going to pay a visit to the neighbors, then we could say in 35 years it opened the door and walked down the steps. It hasn't crossed the lawn or the sidewalk or the street. We struggle to reach the nearest body to us, the Moon, can you even imagine interstellar travel?

I sure hope so because that is what this post is all about.

In almost every Science Fiction story there is a reason to leave Earth. Maybe our home was destroyed, or we were lured off with riches, adventure, and treasure, or maybe we just out-grew the earth and had to leave for lack of room. Another good reason that they never seem to think of is just to have a back-up for the human species.

Let's say for a moment that we had a reason to leave our star-system. A planet wide evacuation would be difficult because I want this to be a near-future hypothetical situation. That many people would not be possible. So, for our purposes let's say it was a back-up of humanity just in case something happened to Earth - this lets us send a small group to colonize another world.

One of the biggest constraints in not technology, but budget. Apollo just sent four men to the moon, yet it strained the resources of our coffers, personnel, and our ingenuity to the limits. Any interstellar launch will be many, many orders of magnitude greater. All launches measure cost by weight. Take a space shuttle. Its purpose was to put cargo in space - human cargo and equipment or supplies. That total payload is the whole raison d'etre, so all cost of maintenance, procurement and launch costs are just for that cargo. If you take the total cost and divide by the weight of the payload, you get a cost per pound to low-earth-orbit. A single gallon of water cost $80,300 on the shuttle! Newer programs cost far less, but remember, it's not going to low earth orbit, but to another star-system. Again, we are not talking far future, but near future, so things like weight and fuel are all tied into a single problem: cost. We theoretically have the technology to build a star ship now, but there is not enough money on the entire planet to do so. Not money available - I'm saying in existence. A program to launch millions of people may not be possible for eons to come.

Let's pretend that we've found a world. The Kepler space telescope picked up an earth-like planet, and after years of observation with first; the Hubble, then the James Webb followed by even bigger and better systems, our scientists decided it would support a colony. It will be a new home for humanity, to hedge our bets and preserve us from extinction. Excitement builds on Earth. Humanity unites to build something truly colossal: our first star ship.

It has a tremendous amount of fuel to allow it to move at fantastic speed. Due to the immense distances involved, it will take hundreds of years for our ship to travel to its destination, a very short time when discussing interstellar travel. Decades, perhaps centuries will be spent accelerating, then that many more to slow it down as it nears the new world. This means that most of the ship will consist of its exotic fuel. Next is life support. This ship will be a home for the colonists for longer than most American cities have existed. There must be food, air, heat, power, and comforts for hundreds of years. There must be a shield on the front of the ship. A grain of sand at millions of kilometers an hour would have an impact like a warhead. This shield will be a heavy piece of ablative armor, perhaps with some sort of deflector field to improve our ship's chances. We should make our ship narrow enough to be protected by a small shield, to save on weight. The math says our ship will be kilometers long.

James Cameron's Avatar star ship is shown above. It actually has a good lay-out. Huge fuel tanks and engine in one end, debris shield, storage and habitat at the other. It's just a little small. A great feature is that the habitat spins to provide the illusion of gravity.


Because our ship will take hundreds of years to travel, the crew is an issue. Nobody on board will live to see the end of the journey. Only their descendants will make the trip. This is called a "Generation ship."

Construction of the ship will be largely done in space - it's far too big to launch from the earth in one piece. Much like we built the International Space Station, it will be launched as parts. The star ship will be expensive. Stephen Hawking talked a bit about this. He pointed out that the people who build the ship will spend a great deal of time and treasure on this huge project, only to see a few people board it, the engines power up and then move out of the solar system, never to return. It will have to be a selfless sacrifice, or perhaps an act of desperation.

Aside from the antimatter - or whatever fuel source we have - the ship must carry the colonizing equipment, life support and everything. Space and weight are at a premium here. We must deduce what the minimum we can send is, and then shave that where we can. The goal is to establish life, in a meaningful way, on this world. There need to be educators, doctors, nurses, engineers, architects - in short all the human resources of Earth. We don't just want this colony to survive, we want it to thrive. We don't need all of that immediately, but we need it when they reach the planet. In addition, we need to avoid inbreeding and the Founder Effect.

So the question is, how few people can we send? How broad a genetic base do we need, and how do we prevent gene pool deterioration? I don't really know. It's hard to find any info on this. I think, from what I've been able to find, that if you deliberately select for genetic diversity you can establish a population with as few as 6,000 - if you maintain a high birth-rate. This is a problem. That pushes the habitat size and needs way beyond what is reasonable. That is more than the crew of a Nimitz class super-carrier!  The big aircraft carriers are like a floating city, but are far too cramped. Even with an open deck, the crew needs shore leave and time off rotation. We can fix this by increasing the size of the habitat to three times the size of a Nimitz class carrier, or reducing the crew. Neither will work. Hold on to your hats, there's a solution, but it's kind of disturbing.

Do you remember the frozen sleep pods in 2001, A Space Odyssey? Yeah, those don't really work. It would be nice if they did. Maybe someday we'll figure out how to freeze people and keep them alive.

2001, A Space Odyssey also failed to have much of a back-up crew. Frozen sleep, if it even worked would not be without fatalities. Two guys left awake to run the ship is not a good idea.

Maybe I should say that frozen sleep doesn't work on developed humans. Embryos are a different story. This brings us to this freaky idea I got from the life cycle of some species of aphid.

In early spring the aphids hatch  out of eggs. They are small, but strangely are all female and born pregnant. They grow and give live birth to their young. These are clones of their mothers, also born pregnant. They give live birth to clones. The cycle continues with each generation producing the next by parthenogenesis until fall. In the fall a mutation occurs. Some are born male and some are born as unfertilized females. Sexual reproduction of these strange aphids produces eggs that can survive the winter.

Wow, you're still reading?

The idea is that you launch a ship crewed solely by young women, about 60 of them, and a hold full of frozen embryos. Of the passengers, only a few will be core crew. The others would be grunt labor or some other occupation like hairdresser. All crew would have time to pursue their own interests on the side, even change career if they wished.

In this plan there are two sets of embryos aboard, one for transit, one for re-population. The transit embryos are all female, genetically tested to ensure that they are similar to simplify medical treatment. They could even be clones. During transit each woman will impregnate herself with one by in vitro, and raise her child to replace her. Thus the population is maintained at a manageable size. As they near their destination they will begin to grow the population, each one having multiple children. They'll open up the habitat sections that were kept sealed to save supplies and expand their space to handle the new generation.

File:Transhab-cutaway.jpg
NASA came up with a concept of an inflatable habitat section for the International Space Station called a Transhab, a concept now being used by Bigelow Areospace to build their own station. This may be a good idea, the living area for the new generation. They can be kept deflated to conserve supplies and prevent transport damage in the hundreds of years before use.


After they land on the planet they will continue as they were. Once they hit about 3 thousand they will open the second batch of embryos. This batch contains genetically diverse male and female embryos, the base of our new population. There will be some cultural problems to sort out - after all these women will have never met a man before. There also will be a period of cultural change as they go from lesbian relationships (if any formed at all) to heterosexual. The shock would be great.

Now, I think this whole thing is a bad idea and really, really creepy. What I want to happen is I want to take my wife aboard a faster-than-light ship to a distant world, and go visit our parents on earth every Christmas. This whole thing was a thought experiment with foreseeable technologies. Who knows, when we leave Earth we might just beam straight to a new place instantly. Guessing the future never works as well as we think it will. Just look how much more advanced our cell phones are than Captain Kirk's communicator.

I can't wait to see the surprises that lie in store for us. How will we leave Earth and when? I would love to know.
 P.S. I promise that the next post will be less weird... well at least a little bit less weird.

Sunday, September 2, 2012

Intelligent Design vs Guided Evolution and real science

I am a christian. I believe God created Heaven and Earth. I believe that He made the stars, planets and matter that make up our galaxy. I believe we are his children, made in his image. I also don't believe in Intelligent Design. Confused?

Don't be. Intelligent Design is not what you may think it is. It is a specific set of beliefs, not a blanket name for Creationism. It is propagated by a specific entity called the Discovery Institute, a christian conservative organization. In theory it is a scientifically based view not influenced by any belief, faith, religion  or preconceptions. In reality it is a christian religious agenda based primarily on a specific interpretation of The Bible. It is best summed up in a quote from them: "Certain features of the universe and of living things are best explained by an intelligent cause, not an undirected process such as natural selection." Intelligent design is NOT the only  form of creationism. It does NOT represent all christianity, and definitely not all creationists. In my opinion Intelligent Design is limited and dangerously restricting as well as misleading, as it is often thought to be the be only christian answer. Let's look at it flaws from both a christian and scientific stand-point.

Intelligent Design limits God

One of the first flaws of Intelligent Design that comes to our notice is that it is dependent on a single fixed view of God. Let us return to this quote: "Certain features of the universe and of living things are best explained by an intelligent cause, not an undirected process such as natural selection." There seems to be an assumption here that God can't direct natural selection, that he must use His direct power. Think about it - it's stating that the "intelligent cause" would not use certain types of creation. Albert Einstein once said "As I have said so many times, God doesn't play dice with the world." (I know I'm taking that out of context), I say God can play dice if he wants, he knows how they will fall. He can always roll sixes if he wants, they are His dice. He knows the end from the beginning. He has the fore-knowledge to be able to set things up so that "A" causes "B" which causes "C" and so on. To our mortal minds it may at first seem like a random process, because we don't know enough to predict the results out of the infinite possible ends. Our minds are not advanced enough to even grasp that. "For my thoughts are not your thoughts, neither are your ways my ways, saith the Lord. For as the heavens are higher than the earth, so are my ways higher than your ways, and my thoughts than your thoughts." (Isaiah 55:9 KJV) I believe God can use evolution as a powerful self-regulating tool.

Intelligent Design is not scientific

There have been no unbiased experiments conducted, no whitepapers published and it has never presented a body of proof sufficient to be taken seriously by the scientific community. Much of what they say hinges on flawed analogies, like the watchmaker analogy - which would be valid if we were talking about mechanical things and not biology. Every specific argument for Intelligent design has fallen prey to research. For example: Bacterial Flagella. These are small hair-like protrusions from bacterial cells that rotate, providing propulsion. Proponents state that the flagella are too complex to have simply evolved; they must be created. A partial flagella serves no purpose and would not provide an advantage. After the the proponents of Intelligent Design made this claim, it was shown that a poison spur on a similar type of bacteria were one protein short of a rotating flagella. In short, it was obvious how it evolved with a single mutation. It is clear that they have much to do and prove to be taken seriously as a viable theory.

Intelligent Design is dangerous to the future of science

I see it as deliberately blind view that things are what they are because God made it that way and that is that, stating that if you don't understand something you should ascribe it to God and call it done. This bugs me on many levels. I want to know how God created the universe. Yes, stating that God made it is true, stating that all things are His handiwork is valid, but not even trying to find out why - proclaiming it to be a dogma that science cannot and should not probe does not rest well with me. If you say that, you fall into the same stagnant trap that forces good people to chose between their faith and logic. It pushes all we do not yet understand into the untouchable realm of God's power. This is not right. Galileo ran up against a system like that. One cannot define science by religion, what exists is what is and deserves to be seen as that. Scripture is vague. In Galileo's time people believed that heaven had perfect spheres called planets. They were symmetrical and geometrically perfect. Along came a scientist who had evidence to the contrary. Today we understand that the Catholic church read into the scriptures things that were not there; they added to their dogma things with no scriptural basis. May I point out that scripture does not state "and verily He poofeth the earth and animals into existence fully formed in an instant."

Science must be allowed to postulate freely. Part of the scientific method is to observe objectively, not within the restrictions of dogma or ANY preconception.

So what do I think happened?

It's fairly simple. This video (you don't HAVE to watch it, but it comes recommended) has some real gold in it. It is produced by Sal Khan, founder of Khan academy.


In this, he states that a self-regulating universe speaks to a more profound God. The very fact that we continue to improve and grow shows that God is not done. The work of God is endless - endless number of creations, endless improvement of His creations and creations that have no end. The form may change, but matter (by the laws we know) can neither be created nor destroyed. Sal Khan also spoke of fractals. I imagine that God would know every whorl that a fractal would have in it in all its infinite complexity before it was done. If you think of the universe as a fractal, things start to get interesting.

We are at the Big Bang. God has looked across all the possible universes, all the infinite combinations and all the ends and chosen the one he wanted. The bang starts. Space and time are warped, the very concepts don't exist yet. As the universe expands, the laws God has chosen snap into place. The electromagnetic force is stronger than gravity. Dark energy, inertia and heat forces everything apart. Antimatter and matter cancel each-other out. In this improbable universe there is a tiny bit more matter. It is not evenly dispersed. As God planned, the irregularities cause it to collapse into clouds then stars. These live and die, they explode into heavier elements, seeding the universe with minerals needed for life. New stars form. Some organize planets in orbit around them from the heavy elements that were scattered. Some form life that grows and evolves into what we see today. God uses this genetic soup as the raw material to create his children on this and other worlds.

Some of these children stand and see the order and patterns and state "this must be the work of a God, I have my faith so I need look no further," others stand and see the same and say "I see how this was done, it must not be the work of a God, I'll look further." Then there are some of us who say "I believe it was God who made it. He is a God of order, let us see how he did it."

I live in wonder of the wisdom and power of God. This world of ours is beautiful and complicated beyond our current understanding, but I would love to understand as much as a mortal is able.