For some time now we humans have discovered that there is a lot more to this world that we live in besides planet Earth. A lot more! The observable universe alone has a diameter of 93 billion light years, but the whole thing might as well stretch out to infinity as far as we know. Only in here we calculate that there are roughly 100 billion galaxies, each with somewhere between 100 to 1000 billion stars. A total number quite difficult to even imagine actually.
But let’s not get ahead of ourselves and instead focus our attention on just our own galaxy, The Milky Way. Because the universe, as far as we know, is expanding, the possibility to visit distant galaxies is extremely close to zero. Nevertheless, our galaxy has about 400 billion stars (about 10,000 for every grain of sand on Earth), 20 billion of which are similar to our own Sun and about a fifth of these have a planet in the Habitable Zone (an area in the solar system suitable for a planet to harbor life as we know it). Now, just for argument’s sake, if just 0.1% of these planets had life, there would be around 1 million planets with life just in our galaxy alone!
Given the age of the Milky Way as compared to our own Solar System, there would have been many opportunities and enough time for at least one alien civilization to develop into a galactic “super power”, able to colonize the whole of the galaxy, or at least a big part of it.
So, where is it and why haven’t we found it? Or better yet, why hasn’t it found us? The galaxy should be full of space ships by now, right? There should have been someone greeting us and holding up banners as soon as we sent the first man into space, but it didn’t happen! This is more or less The Fermi Paradox!
For you to truly understand this principle and what it really implies, what could be the reasons behind it, as well as several solutions, the team at Kurz Gesagt has made two videos explaining the possibilities of why this could be. Hope you enjoy them as much as we have and that they shed some light on one of humanity’s biggest questions: Are We Alone?