Arthur C. Clarke once said, “Two possibilities exist: either we are alone in the Universe or we are not. Both are equally terrifying.”(Good Reads) Every time I read this quote in never fails to give my chills. This blog will discuss the possibility(or lack thereof) of proof of existence of alien life in our Universe.
How big is the Universe?
Our universe is absolutely immense. To be specific, according to Mario Livio, the acceptable range of galaxies in our universe is between 100 and 200 billion. Furthermore, since this topic not the main focus of my blog, I will post a video below to further explain the vastness of our universe.
https://www.youtube.com/watch?v=AC7yFDb1zOA
Are There Other Earth-Like Planets?
For many years, science used logic in order to explain alien life. Given how big the Universe is, the probability of extraterrestrial life has to be extremely high, right? This idea simply does not have any scientific proof and will not be sufficient in many ways. However, astronomers strive their entire career to find an Earth-like planet that is capable of sustaining life as we understand it. This task can be quite difficult though because most planets discovered are too hot or too cold for human life to exist. However, a discovery NASA has huge implications for finding Earth-like planets. “NASA’s Kepler Space Telescope, astronomers have discovered the first Earth-size planet orbiting a star in the “habitable zone” — the range of distance from a star where liquid water might pool on the surface of an orbiting planet. The discovery of Kepler-186f confirms that planets the size of Earth exist in the habitable zone of stars other than our sun.”(NASA) Also, as recent as two days ago, there is growing traction that one of Jupiter’s moons could possibly sustain human life. According to a new NASA study, “Certain tidally stressed moons in the outer solar system, such as Europa and Saturn’s moon Enceladus, harbor oceans of liquid water beneath their icy crusts. Scientists think life might originate in such oceans if they have other key ingredients thought to be necessary.”(Daily Galaxy) These two new discoveries give us hope that Star Trek and Star Wars could be real, instead of just awesome science fiction movies.
Are Humans Alone?
Are we Alone?
Now to the question that cannot be answered with any certainty. Even though I am one of the people that believes that since the Universe is so big, the odds of alien life have to be probable; I will put that argument aside and focus on the scientific aspect. First, and most importantly, in order for life to exist, their must be a significant number of niches that sustain a wide variety of species. There is one planet outside of our solar system that scientists believe could support a life form, however it does come with an asterisk. “Since we do not know exactly how life formed on earth, it is impossible to evaluate this possibility for Europa. One thing is clear, however: if there is life in the Europan oceans, it is likely to be unrelated to terrestrial life.”(Astrobiology and the Search for Alien Life)
Furthermore, this report done by David Morrison, who is a Senior Scientist at the NASA Astrobiology Institute, also discusses the idea of life on Mars. Even though Mars is ‘close’ to Earth in relative terms, there is very little known about this planet. According to Morrison, “there is no reason to think that life could not have begun on Mars about 4 billion years BP, since earth and Mars apparently had similar surface conditions then. Future missions will include the return of samples, selected from sedimentary rocks at sites (such as ancient lake beds or hot springs) that once held water”(Astrobiology and the Search for Alien Life). We will simply have to wait and see if Mars could have supported human life, but I am hopeful that it can.
Here comes the scary part about alien life told by Stephen Hawking. He said, “I believe alien life is quite common in the universe, although intelligent life is less so. Some say it has yet to appear on planet Earth”(BrainyQuote) Also, Hawking said “If aliens visit us, the outcome would be much as when Columbus landed in America, which didn’t turn out well for the Native Americans.”(BrainyQuote)