Are We Alone in the Universe?

5/24/2017 01:06:00 AM

"Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the drug store, but that's just peanuts to space." - Douglas Adam, from The Hitchhiker's Guide to the Galaxy.

As a fan of science fiction books, films and TV Series such as Doctor Who, The Hitchhiker's Guide to the Galaxy or Star Trek, I've always been curious about the matter of extraterrestrial life. All of the storytelling about civilisation exists outside there in the vast void and emptiness of this galaxy questioning the fact: are there other living things outside the earth?

Many explorations have been done in the attempt to answer that question. However as Neil deGrasse Tyson wrote in an essay titled "Reflections on the Scientific and Cultural Implications of Finding Life in the Cosmos" for NASA's astrobiology magazine, life on Earth is the only known life in the universe. Although to some extent, it is possible due to some findings and arguments that says otherwise. The chance could possibly be higher due to recent findings from an unmanned spacecraft that dive into the planet Saturn and its moons, Cassini. According to Jet Propulsion Laboratory California Institute of Technology, Cassini discovered that one of the moons called Enceladus is an active moon that hides a global ocean of liquid salty water beneath its crust. With its global ocean, unique chemistry and internal heat, Enceladus has become a promising lead in our search for worlds where life could exist. Or else, there could be a possible civilisation in that moon, or somewhere in another galaxy.

The question about where are other civilizations or the "aliens" in the galaxy is known as the Fermi Paradox. The theory is famed by physicist Enrico Fermi to speculate on the reason for this lack of contact with the extraterrestrial civilization. With over 200 billion stars in the Milky Way galaxy and 1/2.4 that many earthlike planets (Terzian and Hohlfeld, 1976), there are more places that life could have arisen than we could ever look. If we look back on how old our Milky Way Galaxy is, thirteen billion years old, and compare it to Earth's age which is only four billion years old, a hypothesis emerged that there could be chances for life to develop on other planets in the past. However, none of them has found the technology to make us on the earth notice their civilization.

Nikolai S. Kardashev, an astrophysicist from Russia, in 1963 came up with a hypothetical way to categorize the civilizations that could exist in this universe. He created the Kardashev Scale to measure how advanced a civilization's technological achievements are based on the amount of energy it can access and harness. In his paper titled "Transmission of Information by Extraterrestrial Civilizations", an advanced civilization would have the capacity to transmit radio signals far into the cosmos. He came up with three types of civilizations: Type 1 civilization or known as the planetary civilization would be able to access the whole energy available on its home plane, utilize all the energy that reaches the planet and what it can produce. And we are currently around 0.73 on this scale (we are only an almost type 1 civilization). After the civilization reaches type 1, they possibly trying to find energy from other planets. Then it will turn into type 2 civilization, when a civilization would be capable of harnessing all of the energy of its home star. The way to harness the energy is through a concept called the Dyson Sphere, a hypothetical megastructure to completely enclose a star and capture all of its energy then transfer it to the home planet. Type 3 would be a civilization that controls and possesses its whole galaxy and its energy. Regarding the age of our galaxy, there are other possible planets with life have had more time and build technology to be an advanced civilization, probably even type 2. Or there could be a type 3 with aim to colonize a galaxy that makes their existence would be pretty noticeable. However, the civilization on earth haven't heard a thing or visited by any extraterrestrial civilization. The question about where they are, or the Fermi Paradox are still left unanswered.

However, there's a couple of most discussed ideas and theories through century that could be the solution to the question. To make it easier, let's categorize them into two categories; Group 1 is a couple of explanations that assumes there are no other advanced (as in type 2 or type 3) civilizations because there are none of them out there. Group 2 is a couple of reasons in which why we are not seeing or hearing anything from advanced civilization because they are out there.

Group 1 suggests that if there are thousands of things in our own galaxy, well, there must be something else that has happened before and will be happening again in the future. The theory is called The Great Filter. The theory says that at some point of time, there's a wall that would block and deny civilizations because something (evolution or disaster, etc) happened. So, it's very unlikely and impossible for life to get beyond. The question is; where in our timeline does the Great Filter happen? There are many possible answers to that question. The Great Filter could be behind us, or we successfully surpassed it because we're special. We have surpassed it because the filter is already happened at the very beginning of time of the earth's existence or the filter could be the evolutionary of prokaryote cell to eukaryote cell. However, if The Great Filter is not behind us, the filter could be ahead of us.

Group 2 explanations don't believe in us being special things. They believe in the Mediocrity Principle, that there is nothing unusual or rare about our galaxy, solar system, planet, or level intelligence, until evidence proves otherwise. The popular explanations about this group circling about how our technology is too primitive to perceive them. The simple example of this is like an anthill right next to a highway. Would the ants be able to understand the technology and the intentions of the highway is? How do they communicate things to the people in the highway? If there are type 3 civilizations out there, we probably can't pick up the signals from their planet using our technology yet. Or higher civilizations are aware of us and silently observing us, it's called Zoo Hypothesis ("look but don't touch" kind of experiment). However, if there are any civilizations out there who wants to travel to our milky way and could travel at the speed of light, it will still take nearly 100,0000 years just to cross it.

Group 1 & 2 solutions, unfortunately, have the same one problem; where are the borders of technology? One thing for sure, in the midst of new-born and mindblowing technologies, is that we really don't know anything. From the beginning of human civilizations on earth, we have spent more than ninety percent of our existence as hunters and gatherers, and we've only stopped using human labors as the main source of the energy 200 years ago. If we compare it to the timeline of the earth's existence, our high-tech civilizations is actually still a baby. Right now we may not know what is the answer of this Fermi Paradox. Don't fret because there's only one way to find out and we still have a long way to go to finally know anything.

0 Comment(s)

Comment here