The Universe, is it eternal or did it begin in a “Big Bang”. Well, I’m getting older, but I’m not that old, so I wasn’t standing around to see. It could have very well always have been here. No one knows but many scientists conjecture from evidence that the Universe began in some sort of infinitely compressed form which exploded into the remarkable display we see today. They even posit that they found an echo of the original explosion.
However it originated it remains today in a state of continual change, expanding ever faster, ever farther.
In the distant reaches of space we see vast clouds of dust, and in the midst we see the birth of new stars, perhaps new planets, maybe even future homes for life. Stars, the furnaces of the Universe, supplying vast energies, generously sharing of themselves, utilizing their vast stores of hydrogen. Without the stars, life as we know could not exist, and for more than the just the reason that they provide steady energy upon which we all depend. Vast stars, many times more massive than our friend Sol, upon the complete consumption of their hydrogen fuel, begin to collapse. Their volume, no longer able to be maintained by energy output, begins to shrink. Compression continues to a critical level, helium begins to develop, then the star explodes… a supernova occurs. This releases enormous quantities of various heavier elements, spreading them into the ether.
Without these heavy elements produced in the furnaces of these massive stars, rocky planets such as ours could never exist. Our very bodies would never have come to be.
The molten remains of these stars, having been belched out eventually coagulate and form, yet, again, stars, but not just stars, but also further material which orbits these new stars and which as time passes, gathers to form planets. As more and more of these new planetary systems form, the chances increase that in at least one system one planet will form in the right orbit around the right star, producing conditions which allow organics to form.
Scientists speculate that once conditions developed that were complementary to the formation of monomers, produced by prebiotic synthesis, which have the ability to link to other monomers and form polymer chains, RNA spontaneously arose. RNA formed which had the ability to replicate.
At this point evolution began to act. Over the eons of time, perhaps a billion years, RNA converted to DNA. This was accomplished by the loss of one oxygen atom. DNA… capable of self-replication, and of synthesizing RNA.
Self-replication started the evolutionary ball rolling. Natural selection favored variants of the replication process allowing for increased complexity. The various strands eventually led to variants that had a cell enclosure which outcompeted the various ‘naked’ variants. These cell enclosed variants eventually developed specialized functions upon combining with other cells, and multicellular forms developed. These became the first multicellular organisms.
Well, that’s the way I see it, anyway. There are no doubt mistakes in my presentation, if that prompts an investigation then I will have been successful. There is still much work to do, many “God did it” holes to fill. There are many questions at many levels. I suppose we could quit, stop investigating, throw up our hands, return to the Dark Ages… but I hope we don’t. I find it fascinating.