Universe: The Known Unknown
“The Universe is under no obligation to make sense to you.”
― Neil deGrasse Tyson
How many times have you just looked up after a tiring day and somehow calmed down? Looked at the stars brightening up the sky and questioned many things, even your own existence? Wondered what it will be like up and beyond our sight?
Well, you are not alone.
We humans have been fascinated by the skies for a very long time, enthralled by its perplexity. The vastness of the universe has always had its own way of calming the chaos of our mind, captivating us with the mysteries it holds inside.
The universe was unknown, featureless, and just dark for a very long period in the past. However, with the wonders of our mind, we have now recognised the smallest particles to the biggest of galaxies. We were often told in childhood, ‘The sky’s the limit,’ but now we have far surpassed that diving straight in the cosmic dark.
However, the more we dive into the mysteries of the universe, the more mysterious it becomes. Our universe is a dynamic and expanding one that we try to make sense of through the field of science. One of the key features of science, however, is the reality that the more you know, the more you realize you don’t know.
In terms of the universe, the unknown far dominates the known. Even with our hi-tech equipment and rapid advancement in science, we, “the privileged species,” have access to only a finite amount of the universe. Thus the information we have access to and can obtain is also limited. As Fabiola Gianotti, Director-General of CERN (the European Organization for Nuclear Research), said: “95% of the universe is unknown to us.” This 95% consists of dark matter (26.8%) and dark energy (68.3%).
Ordinary matter
Now focus on the remaining 4.9%. Believe it or not but humans, along with everything on Earth, and everything we have discovered in the cosmos is included in just that 4.9% of the observable universe. This small rare portion of matter, suspended in the vastness of the universe, is known as ordinary matter (ironic enough?).
Although our path of knowledge about the mysterious dark matter & dark energy is filled with darkness, still the scientists across the world have tried to lighten it a bit by trying to understand their importance in the workings of the universe.
Dark Matter
Dark Matter is responsible for structure formation in the universe, such as galaxies. It binds the celestial objects together, adding gravity to galaxies and other cosmic bodies. Scientists have been unable to observe it directly as it can’t interact with ordinary matter, yet they are pretty confident about its existence. If not for the gravitational effects of this unseen mass, the stars inside the rapidly spinning galaxies will hurl out of the system; the universe will literally fall apart. Thus, this unknown force practically holds the universe together.
Dark Energy
In 1929 Edwin Hubble concluded that the universe is expanding by observing the exploding stars, also known as supernovae. It was observed through the telescopes that galaxies were moving further and further away, indicating an expansion. It was thought that the force which holds the universe together would eventually put a brake on or at least slow down this expansion. However, in the 1990's, once again, a team of astrophysicists turned their heads towards the receding supernovae and observed that not only is the universe expanding, but the expansion is also speeding up. It was believed that a mysterious force was counteracting gravity. Dark Energy is believed to be the force that is responsible for the speeding expansion of the universe, causing objects to move farther and farther away from each other.
Whatever mysteries the Dark Matter and Dark Energy are, they both can be understood by imagining a cosmic game of tug of war between them. Dark Matter holding the universe together while Dark Energy pulling it apart.
Though we might never know anything for sure, we have tried to understand the universe and its workings through theories based on our assumptions and observations. Yet there are many known unknowns in our known universe, and probably they will stay that way. What we can do is keep seeking knowledge about this expanding universe.
We are often baffled by the mysteries in our favorite detective shows, while we just need to turn our heads up for the most baffling of the puzzles.
So, put on your best detective hats, let your curiosity fly high
Explore the vastness and beauty of the stars and the sky
With a serene feeling in the heart
Let us start an enchanting journey exploring the enigma of the cosmic dark.
