Earth is small. Many people find it hard to believe, but when one thinks of earth in its context, amongst billions of galaxies, stars, planets, and an infinite universe, earth is a mere grain of sand on the beach that is space. With this in mind, one may, quite understandably, find it hard to believe that earth is the only planet that sustains life. With today’s advanced technology and science, extensive evidence has been found suggesting a great likelihood of life on other planets. The discovery of life on other planets has huge implications for humankind, as it would likely give a more thorough understanding of what human life is, how it came to be, and possibly even insight into why humans exist.
Oftentimes, people ignore rhetoric regarding the possibility of life on other planets. This may be for religious reasons or because many people see it as more science fiction than scientific, but there is a substantial difference between Hollywood’s perception of aliens and what is likely to be the first extraterrestrial life discovered (Borenstein). In all reality, carbon, hydrogen, oxygen, and a few other basic elements are all it takes to create the miracle of life, and these chemicals could exist in countless places other than earth (Bryson 2). Some life may not even require that, like the microbe found in a lake in California, which was able to survive on arsenic and phosphorus alone (Borenstein). According to Borenstein, the “life” that scientists are looking for is more accurately described as a life form or microbial slime, much like the microbes that became humans via evolution.
Approximately 140 billion galaxies inhabit the universe, with somewhere between one hundred billion and four hundred billion stars in Earth’s galaxy, the Milky Way, alone (Bryson 27). In 2010, a Yale University astronomer estimated that there are about three hundred sextillion stars in the universe (Borenstein).
With the knowledge that very little is needed to actually create life and some idea of how vast the universe is, the question of where life could be sustained is key. The two main players in this area are so-called “super earths” (Spotts) and the appropriately-named “Goldilocks zones” (Borenstein).
A “super earth” is a planet with approximately two to ten times the mass of planet earth (Spotts; Borenstein). The mass of a planet is crucial in the possible sustenance of life, especially in regards to intelligent life. If a planet is too large, species will likely die out, as procreation would be extremely difficult; meanwhile, if a planet is too small, it will likely become over-crowded very quickly, causing life to die out (Kaufman). NASA’s Kepler mission, one in which a spacecraft known as “Kepler” trails behind the earth in orbit taking photos and analyzing outer space, was launched in 2011. By September of that year, it had identified multiple previously unknown possible super earths (Spotts). Scientists estimate that about half the stars in the...