The Vastness of Space: Understanding the Cosmos and where are all the Aliens?

Space has interested us as far back as the dawn of humanity. It has become quite the realm of our fantasy. Nothing makes a good debate as much as the existence of extra-terrestrial life does. Rightly so, humans have always used space as a measuring stick to validate themselves.

"Every one of us is, in the cosmic perspective, precious. If a human disagrees with you, let him live. In a hundred billion galaxies, you will not find another." - Carl Sagan

Perhaps it's the fact of belonging to something so complex, vast and elaborate that interests us or maybe it stems from general human curiosity. It can be observed in history that humans have always been doing things that seemed impossible, and that is what separates us from any other species. Humans have always expanded the confines of possibility with curiosity and sacrifice. Space is huge. I'm sure I don't have to explicitly define how small our triumphs are in the face of this mighty universe. Let alone the universe. The earth doesn't even make up for 1% of the mass in our own solar system.

"The sun lies at the heart of the solar system, where it is by far the largest object. It holds 99.8 percent of the solar system's mass and is roughly 109 times the diameter of the Earth — about one million Earths could fit inside the sun."

I'm sure I've put that into context for you now. Yet, humans have, in the earliest recorded years of history, managed to associate planets and stars with figures. The earliest cultures correlated planets with gods of rain, drought, seasons etcetera.

We live in a quiet part of the Milky Way galaxy, a spiral of average size, roughly 100,000 light years across, consisting of a plethora things such as stars, gas clouds, asteroids, dark matter and of course, to everyone's dismay, black holes too. Pictures may make you think that the Milky Way Galaxy is very dense, cluttered with a lot of things, but in reality, it is a lot of empty, dark space, kinda like my soul. Only kidding. I don't have a soul.

Even with our current technology, it would take roughly a few thousand years to get to the nearest star. However, the milky way is only one of many galaxies in the local group, which is a part of a supercluster, which is part of a million of superclusters in the entire observable universe.

With trillions of habitable planets, it should be easy to find alien life, right? Well, that's what the Fermi Paradox is. So there are 100 Earth-like planets for every grain of sand in the world. Think about that next time you’re on the beach. But we are small. Very small. The likelihood of reaching a civilization that is intelligent is very minute. We are yet to develop the technology that can reliably get us to the moon, let us not talk about other stars.

I don't know what all this means, or if it means anything at all. All I know is that humanity and planet Earth have a special bond. One thing we do have to acknowledge is that we don't really know anything. Humans have spent nearly 90% of their existence as hunter gatherers. 500 years ago we thought we were the center of the universe. 200 years ago we stopped using human labourers as the main source of energy. Only 30 years ago we had nuclear weapons pointed at each other because of political disagreements. In the galactic timescale, we are still embryos. It may be easy to imagine that we are the centres of the universe, but in reality, we make a very small difference to this universe. We don't know, and maybe we never will. Here we are now, living in a thin layer, on a small, wet rock. We are really lucky, and we better start acting like it.

Thanks for reading.