Are we All Alone in this Universe

Can you answer the question of whether you're alone in the universe? Or are you connected to anything? Well, you're part of a group of mammals that's relatively new in the grand scheme of things. Despite this, humans have achieved great things like building Large Hadron Colliders, making YouTube videos, and even creating Pokémon. Humans originate from an ancient lifeform that first emerged around three and a half billion years ago. While we like to think we have control over the planet, the truth is that we don't. A single asteroid impact or a new virus could easily wipe us out. Although humans are capable of destroying the planet, we would probably only succeed in causing a major mass extinction event, at best.

Isolated in the universe or connected to anything? Humans belong to a young group of mammals that have achieved remarkable feats like building Large Hadron Colliders, creating Pokémon, and producing YouTube videos. Despite the illusion of control, humanity's existence is fragile. A creative virus or a small asteroid could potentially wipe us out completely. Even with all our nuclear capabilities, we would likely only cause a massive extinction event at best, leaving most microscopic life and subterranean creatures largely unaffected. On a geological time scale, our impact on Earth is insignificant. We live on a tiny, watery planet that orbits a massive burning ball of plasma, which will one day cease to exist and most likely annihilate us in the process. Assuming we survive the death of the Sun and colonize the galaxy, we might endure until the last star in the universe fades. Beyond that point, life will likely become impossible. So, with everything ultimately coming to an end, what does this imply for you as an individual?

At one point in your life, you were just a single cell inside your mother's womb, only 0.1 mm in diameter. But today, you are made up of about 50 trillion cells, each one a complex biological machine much larger and more complex than the average bacteria. These cells follow the laws of physics and chemistry, using micromachines to carry out various functions such as building proteins, generating energy, breaking down food, transporting resources, transmitting information, and reproducing. They communicate with each other, fight off invaders, and carry out specialized tasks to keep you alive and well. But with trillions of these tiny building blocks, where does the "you" part come in? The basic information that defines "you" is stored in your DNA, a molecule that contains the genetic instructions necessary for the development and functioning of all known living things. If you were to stretch out all of the DNA in your body, it would measure two meters in length! When combined, the DNA strings in your cells would stretch to Pluto and back to Earth. This DNA is a direct link to your very first ancestor.

Consider this for a moment: in every cell of your body, there exists a tiny strand of matter that has existed in various forms for 3.4 billion years. This strand has evolved, mutated, and multiplied trillions of times, but it directly links you to the first living organism on Earth. You could say that your DNA has touched every living being that came before you. However, you are more than just your DNA. Your body is composed of seven octillion atoms, which is equivalent to seven billion billion billions. Around 93% of the mass of the human body consists of just three elements: oxygen, carbon, and hydrogen. Oxygen and hydrogen are mostly found in water, which constitutes about 60% of the body's weight. Carbon is an essential element for life, as it easily bonds with other atoms, enabling the formation of long, complex chains of molecules that constitute the solid part of you. The remaining 7% is a journey through the periodic table of elements: nitrogen, calcium, phosphorus, potassium, sulfur, sodium, chlorine, magnesium, iron, fluorine, zinc, copper, iodine, selenium, chromium, manganese, molybdenum, cobalt, lithium, strontium, aluminum, silicon, lead, vanadium, arsenic, and bromine… that's quite a lot!

Fun fact: no matter what your favorite music is, you're about 0.5% metal. In addition to oxygen, carbon, and hydrogen, your body is made up of a variety of other elements like calcium, phosphorus, sodium, and more. These elements perform various essential functions, including transporting oxygen, building bones and cell structures, carrying signals, and driving chemical reactions. Your body is constantly changing and renewing itself. Every 16 days, about 75% of your body is replaced due to the exchange of water. Each year, nearly all of your atoms are replaced by new ones, and in just 5 years, almost all of the atoms that make up your body were not there before. So, in a sense, you could think of yourself as a temporary collection of atoms.

Where did the atoms in your body come from? At the beginning of the universe, there were mainly hydrogen and helium atoms. Over time, enormous gas clouds formed and grew denser until they collapsed under their own gravity, giving birth to the first stars. In the cores of these stars, hydrogen was converted into helium under extreme conditions. After millions of years, the hydrogen became depleted, and the stars started dying. Under super-extreme conditions, all elements known today were created just a fraction of a second before the stars died and exploded in supernovas. The supernovas scattered most of their contents into space, while their cores collapsed and became black holes. These elements drifted through space for an unknown period of time before arriving at a different cloud that was slowly forming a new star- our Sun.

The same elements that were once present in the core of a star eventually formed planets, and some of those elements ended up on Earth, making it possible for life to begin. Thus, we are directly linked to the first stars that ever existed in the universe. We are a part of the universe, and the concept of being a tiny but deeply connected component of an immense structure is truly awe-inspiring. While we cannot say for sure what it all signifies, we do know that we are made up of small components that tie us to everything in the cosmos, stretching back to the very beginning of existence. It's a comforting notion that we are never truly alone, and never have been.