OK. So this isn't my usual post (if there even is a usual anymore). It's all science-y and pseudo-sciene-y and if you think the Earth is 3000 years old maybe this isn't the diatribe for you. The following is something that's been knocking around my gourd for sometime. I wanted to get it out. It's more for my personal use, but if it interests you, so be it. I always welcome informed and level-headed discussion.
Most women make one egg available for fertilization each month. The average human male ejaculate has 200 to 400 million sperm. That's the number needed guarantee conception on multiple occasions throughout an adult woman's lifespan. Only one baby is born at a time (normally) because the survival rate of humans is fairly high. Contrast this with other animals like Frogs who spawn thousands of offspring, most of which will perish in short order. But those thousands are needed to ensure that enough survive to propogate the species. And outside of some calamity most species can and do survive.
Tuck that bit of information aside and come with me down the rabbit hole. I'm fascinated by science and people striving to understand the universe. I've watched countless hours of shows about black holes, how life began and how the universe works in general. Recently I've become enamored with how life came to be on this planet. So if you'll indulge me I'd like to go over some of the important things, we think, that make life possible on this blue marble.
First up is our galaxy. While not essential, it's certainly a good thing that we reside in a stable galaxy. We're not currently colliding with another galaxy. The spiral arms are well formed and for the most part there is a kind of order to things. What is essential is our location in the galaxy. Too much closer and the radiation bombarding our solar system would be to great for life to exist. Too much further out and there might not be enough varied elements to foster life. So we're in a Goldilocks zone of sorts in the Milky Way.
We are also in the Goldilocks zone in our own solar system. Not to close to boil and not so far away to freeze. But wait. There's more. The sun is constantly bombarding us with harmful radiation. To combat this the Earth's spinning molten iron core creates a magnetic field that protects all life. Without the magnetic field, the solar wind would blow the atmosphere right off the earth like the after effect of some cosmic birthday wish. Why does the Earth have a molten core? Some folks much smarter than myself claim that when the sun was created it was spinning at a high enough velocity that when the planets formed they too were spinning fast enough to create a sustainable, spinning iron core.
Mars also HAD a molten core at one time, but it has long since seized. Why did it seize? Some think a catastrophic cosmic impact caused a chain reaction that shut down the core. Others believe that Mars was just too small and that over time the planet just cooled enough to where the core locked up. Either way, after lock up, the atmosphere was blown off and we're left with the red planet we know and love today.
Recently I read an article about the sun. It seems that while the sun in its present form provides us with just enough warmth. If we turn the clocks back millions of years, the sun should have been 30% cooler and therefore the Earth should have been a block of ice for a really long time. This, of course, isn't the case so they are struggling to find the answers. One possible explanation is that the sun used to be much bigger and some cosmic event blew a bunch of the suns outer layers away. If true I'm guessing it makes life here and elsewhere that much more improbable.
So now that we have a warm planet with a strong magnetic field we need life. And life as we know it requires water. That's where things get interesting. Hydrogen and Oxygen are two of the most plentiful elements in the universe, so it stands to reason that water is in abundant supply (most of it probably frozen). And we also know that life is tenacious at the microbial level (maybe at every level). We've woken up microbes that were in a state of suspended animation for hundreds of millions of years. Through models we've demonstrated how life can survive even in the face of near total planet annihilation. Once life takes hold, it's near impossible to completely get out. Also, I've recently read that some scientists believe that some organic compounds are actually formed in stars and shot into space. Weird. Eerie.
That's why I believe that while we haven't found it yet, it is a safe assumption that the universe is teeming with life. We've even proven that life, fundamentally different than we know it, can and does exist. Truly crazy stuff.
While liquid water is essential to how life developed on this planet it is also present in Goldilocks type quantities. Too much water and there is no or little land. The chances of intelligent marine life becoming self-aware and building technology to leave Earth become exceedingly improbable (see dolphins). Too little water and it all exists far below a dried, cracked, barren surface. We have just enough to have ample land and a weather system that waters most of it.
So at this point we have warmth, water, and protection. Now all we need is time. Time for life to travel from simple to complex. From microbes to mammals. But the time for life to flourish is finite, short even given a cosmic context. As soon as the sun ignited it was on a clock. It has a lifespan, albeit a very, very, very long one. But a lifespan nonetheless. Also there is the matter of cosmic collisions. While it is great that we exist in a stable galaxy it is doubly great that we exist in a fairly stable and predictable solar system. We've got our share of errant rocks, but the planets, for the most part, have stable orbits. Even with this stability the Earth is under constant bombardment, and every once in awhile a rock the size of Nebraska will hit the earth, kill most everything and hit the cosmic reset button on the development of life.
These huge impacts have happened about 6 times (maybe a couple more) in Earth's history. More frequent are the asteroids or comets that are big enough to wipe out the majority of life, but leave some survivors. Mammals are the survivors of the last great impact, the one that took out the dinosaurs. Mammals are currently on the hot seat with no friend to phone.
So what's keeping Earth safe now? Luck, mostly, but we have a big brother who helps out once in awhile. I'm talking of Jupiter. It is so massive and it's gravity so strong that it acts like the solar system's Roomba. Some say that without the mighty planet, Earth would experience great impacts on a much more frequent basis and as a result life would never really get going.
So now we exist in a brief window of opportunity, a period between cosmic impacts. We are developing technology at a brisk rate, but we lack urgency. Until we can permanently exist separate from the Earth all of our eggs are in one basket. Some will take the narrow view and declare that we should live simply, like our ancestors. Live off the land in harmony with nature. They think those untouched, primitive tribes in South America do it right. They represent how the human animal should be.
I personally can't abide. From a biological standpoint, the explicit purpose of any animal is to reproduce and sustain the species. The need to reproduce is the single biggest drive in every animal on the planet. There's a damn good reason why sex is always on the brain. So if our base instinct is to survive and reproduce, and we understand that another major cosmic impact will happen (it's not an if) then our focus should be to be able to live independent of the planet. Then independent of the solar system. Then independent of the galaxy. Of course it isn't our focus, but that's another post for another time.
Then there's the idea of intelligence itself. There are several animals with large and complex brains. Bottlenose Dolphins, Asian Elephants, and many whales have brains that are bigger than ours, but for one reason or another they can't reason and think abstractly. They aren't self-aware. Could we have evolved with intelligence but never ever progressed to thinking, reasoning, and above all evolved into beings infused with a curiosity to explore and an innate desire to improve our situation? I wonder.
So to recap. Earth is located in a Goldilocks zone within a Goldilocks zone. It's big enough and spinning fast enough to sustain a liquid iron core that creates a life-saving magnetic field. It has just enough water to make intelligent life possible, and a gas giant like Jupiter orbiting deep in the solar system absorbing collisions that would decimate Earth. And we exist in a calm period in Earth's history in between major cosmic impacts. Some would cite these facts as obvious evidence of God. If the universe were a small place I'd agree. But it's the staggering numbers of planets and stars and galaxies and filaments in our universe that make our impossible string of happy accidents downright inevitable. It's all about numbers. That's not to say that God doesn't exist. I have no idea. Anyone who claims to know definitively one way or another is pushing an ideology.
What's interesting to me are the "what ifs" (and this is where this whole mess of a post comes together and my crazy comes out.). I see the universe as efficient and purposeful. Everything has a use. Everything has a reason for being. If there is no purpose, why does it exist at all? So if there is a reason for everything, why is the universe so damn mind-boggling big?
Some ("some" doesn't suggest a minority or that they are wrong or fringe lunatics) argue that our existence, the existence of the entire universe is an accident. That the random appearance and interactions of elements in the early universe set in motion the largest chain reaction in the history of everything. That we are just an after effect of the big bang and nothing more. To these people I have no rebuttal. Nothing. Since proving a purpose to the universe is impossible (I'm not sure science even has the vocabulary to even form the question) there is nothing else to believe other than the accident.
I'm not wired that way. It seems self-evident to me that we are here for a reason, that the universe has a purpose. Since nature traditionally doesn't expend more energy than it has to, the Big Bang seems like a huge waste of energy if it really was happenstance. Since it can't be proven I hold it as my belief, my reality, and if you believe the opposite I can't say I blame you. But my belief brings me to the BIG QUESTION. THE BIG IF. It's an uber cool question that those people on the other side wouldn't even think to ask.
What if the purpose of the universe is to grow a self-aware, intelligent species capable of breaching the fabric of the universe itself?
Say you had to design a universe that had its own laws, laws that you could not break. You could make the moment of creation, but everything else had to unfurl as dictated by the chain reaction at time zero. And if your purpose for making this universe is to 99.99999% guarantee the creation of an intelligent/self-aware species or species(pl) capable of liberating itself from the bounds of the universe how big would it have to be to take into account all the little possibilities, all the endless variables of life and creation? How big would it have to be so that if two or more races escaped their planets that they probably would never even bump into one another (because there is a chance they might wipe each other out)? I'm no mathematician, but I'll fat thumb guess that it would have to be about this big.
What is beyond the universe? How can we escape the bounds of space/time? Why would the universe be designed for this?
I have no friggin' clue. Not even enough of a clue to make a fevered guess. I don't think we'll have answers for untold millennia assuming we survive that long. And when we do reach the restaurant at the end of the universe (I'm an optimist) the chance of me being right is barely north of zero. But if I'm really lucky, inadvertently-stepping-out-of-the-path-of-a-bullet lucky, perhaps there is a nugget of truth in here somewhere.
It's beyond awesome that we are able to think about it at all.