There\u2019s been lots of very weird American talk about the aliens in the last two years or so. \u201cWeird\u201d because usually their government seems to deny and\/or suppress such \u201cleaks\u201d, and this time it looks very much like they\u2019re the source. So, what\u2019s my take on it?<\/p>\n
When I was a kid, I thought the existence of aliens was a sure thing \u2013 all those UFO and abduction reports had to be at least partially true, the size of the Universe practically guarantees that someone is out there, and sooner or later someone would figure out a way around the limitations posed by the speed of light.<\/p>\n
The change in my thinking happened when I researched a few things for completely unrelated reasons; I researched evolution of life and mass extinctions, and I realised that our existence is contingent upon multiple extremely unlikely things. For instance, single (non-binary) stars are extremely rare, and binary stars tend to produce solar flares of extreme strength that routinely sterilise the habitable zone. I hear it commonly claimed that our Sun is an average, ordinary star, but that\u2019s actually very far from reality. Our Sun is extremely well behaved for a star, and that\u2019s a necessary condition for life not having to reboot after every major solar event. Also, the solar system is very unusual in a sense that it doesn\u2019t have gas giants closest to the star, and instead has them in the outer system. Furthermore, Earth has an extraordinarily powerful and stable magnetic field, which is the reason why it doesn\u2019t look like its twin planet, Venus, and the smaller sibling, Mars. This magnetic field, along with axial stability, seems to have a common cause \u2013 the Theia impact in the formative phase of the solar system, where a Mars-sized planet collided with Earth, and the ejecta from the impact formed the Moon. Apparently, the heavy core of that planet merged with the Earth\u2019s core, while the lighter parts formed the Moon, leaving the Earth with twice the expected amount of heavy elements, whose radioactive decay keep the Earth\u2019s interior liquid, and core spinning. There also seem to be some atypical things about Earth\u2019s core that are still poorly researched, which might actually contribute to the magnetic field\u2019s strength. Also, the Moon seems to axially lock the Earth, making it an extremely stable environment for the evolution of life.<\/p>\n
Life itself in its most basic form seems to have come from space, and the evidence for this is that we\u2019ve found all the basic chemicals for it on the asteroids and comets, and the earliest life on Earth seems to have formed as soon as the planet itself solidified enough. So, life had a very early start here, and yet it took an inordinate amount of time for it to form multi-cellular organisms, and the amount of luck necessary for that to happen seems to be extraordinary. I used to think that life itself is unlikely, but once you get it started, it will eventually evolve into intelligent life. However, based on what I\u2019ve learned, the opposite seems to be the case. Life itself might actually be quite likely, and will probably start whenever the conditions are even the least bit favourable. Anything more complex than the simplest single-cell organisms without a defined nucleus and organelles, however, might be extremely uncommon and likely requires singular extremely unlikely events across billions of years.<\/p>\n
Then we come to radiation. There\u2019s cosmic radiation, and then there\u2019s solar radiation. Earth has multiple layers of shielding against both \u2013 there\u2019s the magnetic field, then the thick atmosphere, and then there\u2019s the ozone layer. Without those, life might exist in the deep oceans, but not on land. Also, without the magnetic field, the oceans would evaporate into space, like they did on Mars, and probably on Venus as well, if they even formed in the first place.<\/p>\n
I\u2019m not saying that life is impossible somewhere in the atmosphere of the gas giants, or in the oceans of their satellites. I would actually be surprised if it didn\u2019t exist there. However, I would also be extremely surprised if we found anything multi-cellular.<\/p>\n
Our kind of life \u2013 multi-cellular, on the ground and not in a liquid or gaseous medium, complex, intelligent, and forming a civilization \u2013 has so many extremely unlikely prerequisites, that I became convinced that as large as the Universe is, it is too small for this to happen more than once. Earth indeed seems to be the centre of the Universe, if we define central in the terms of significance, because everything of significance seems to happen here. Sure, the Universe is big, and full of stars and black holes, rocks, dust and gas, but rather than being a \u201cpale blue dot\u201d of insignificance in the middle of nowhere, Earth seems to be the most special planet around the most special star, where extremely unlikely things occurred across time, to make everything we know possible.<\/p>\n
My next argument against aliens is that, if they exist, they are inconsequential. We can argue back and forth as to why an alien species would come here, and produce nothing more than sightings of unexplained things, and occasional abduction testimony, but the fact remains that if the aliens are here, they are doing nothing of consequence as far as human life is concerned. If something is inconsequential, I\u2019m certainly not going to dedicate much thought to it.<\/p>\n
Sure, something might happen to change my mind \u2013 for instance, if aliens actually do exist and contact us, then they will cease to be inconsequential, and I will have to revise my ideas about how common our type of life is in the Universe, but so far it seems to be that the more we know, the more special Earth seems to be.<\/p>\n","protected":false},"excerpt":{"rendered":"
There\u2019s been lots of very weird American talk about the aliens in the last two years or so. \u201cWeird\u201d because usually their government seems to deny and\/or suppress such \u201cleaks\u201d, and this time it looks very much like they\u2019re the … Continue reading