Chapter 1: The Legacy of Science Fiction

Many of us who were influenced by the imaginative works of Jules Verne, such as From the Earth to the Moon and Around the Moon, recall our awe for these stories. While Verne himself did not delve into the subject of alien life, his creativity ignited the imaginations of subsequent authors, paving the way for a surge in science fiction literature focused on extraterrestrial beings. This article seeks to investigate the scientific rationale behind the potential existence of life—be it intelligent or otherwise—beyond our own planet.

In our high school chemistry classes, we learned that all chemical elements are classified as inorganic. However, certain combinations of these elements can form organic materials, which exhibit characteristics typical of living organisms: they can move autonomously, experience thirst and hunger, and possess instincts and cognitive abilities. These traits remain one of nature’s greatest mysteries, which we will not fully unravel here. Instead, we will focus on the transformation from inorganic to organic, offering insights into the likelihood of extraterrestrial life.

In 1952, a chemistry student named Stanley Miller conducted a groundbreaking experiment that showcased how organic compounds can be synthesized from inorganic materials through simple processes. This experiment is now recognized as a pivotal moment in the scientific advancements of the 20th century. Miller, a pupil of Harold Urey—who won the Nobel Prize in Chemistry in 1934 for discovering deuterium—proposed this experiment to Urey, who, after some initial doubts, agreed to proceed.

They simulated the primordial ocean-atmosphere interactions of early Earth, continuously introducing steam into a mixture of methane (CH4), ammonia (NH3), and hydrogen (H2). The mixture was subjected to electrical discharges, mimicking the effects of lightning. After a week, Miller observed the formation of amino acids, the fundamental building blocks of cellular life. Lightning and the inorganic compounds utilized were abundant in the conditions of early Earth.

The Miller-Urey experiment established that the origins of life are not merely the stuff of science fiction but rather a burgeoning field of serious scientific inquiry. Numerous researchers have corroborated Miller’s findings, and subsequent studies have synthesized an even broader array of amino acids than those produced in his initial experiment. The straightforward nature of these reactions increases the likelihood that similar processes have occurred elsewhere in the universe, potentially leading to the emergence of life.

However, the laboratory synthesis of amino acids alone does not resolve the complexities involved in the development of life. Long chains of amino acids are necessary to form peptides and polypeptides, which are crucial for creating proteins—the essential components of living organisms. The challenge lies in ensuring that these lengthy sequences consist of the correct order of amino acids and peptides to generate various types of proteins vital for life. Many scientists assert that creating these intricate sequences in the lab is unfeasible. Yet, these complexities are merely a testament to human intellect; for nature, such intricacies are quite natural.

Understanding these intricate systems is “the great unsolved problem in physics,” as noted by Stephen Morris, a physicist at the University of Toronto. “How do we deal with these far-from-equilibrium systems that self-organize into remarkable, complex entities like life?”

The concept of extraterrestrial life has captured the interest of many prominent scientists. One such figure was Enrico Fermi, an Italian-American physicist awarded the Nobel Prize in Physics in 1938 for his groundbreaking work on radioactivity. During a casual discussion in 1950 with fellow physicists about recent UFO sightings and the possibility of alien life, Fermi abruptly posed the question, “But where is everybody?” This query highlighted the inconsistency between the absence of evidence for extraterrestrial life and the high probabilities suggested by other scientists. This conundrum is now referred to as Fermi’s Paradox.

Let’s contemplate Fermi’s question for a moment. How does the size of our solar system compare to our galaxy, and subsequently, the universe? Recall that one astronomical unit (AU) is the distance from the Earth to the Sun—approximately 150 million kilometers or 8 light minutes. Our solar system spans about 100 AU in length and 60 AU in width, defined by Pluto's aphelion and perihelion.

In the grand scheme, our solar system is minuscule. The Milky Way galaxy is estimated to be between 6 and 10 billion AU in length, while the Andromeda galaxy, a prominent feature in our night sky, is ten times larger than our own. Each of these galaxies is home to billions of stars like our Sun, which in turn host billions of planets. Modern astronomical estimates suggest that the universe comprises around two trillion galaxies.

Thus, we grasp the relative smallness of our solar system, even if these astronomical figures are difficult to comprehend. However, common sense suggests that if life exists within our solar system, the chances of extraterrestrial life elsewhere are exceedingly high, potentially in millions or even billions of locations.

The findings of Miller, combined with a probabilistic analysis, support the hypothesis of extraterrestrial life. The pressing question remains whether such life will ever be detectable by humans using our most advanced telescopes and spacecraft.

Chapter 2: The Power of Speculation in Film

In the meantime, we can continue to find great enjoyment in speculation and creative narratives. One of the most iconic science fiction films, The Day the Earth Stood Still (1951), features a humanoid alien visitor who arrives on Earth, accompanied by a formidable robot, to convey a crucial message to humanity.

The alien and his robotic companion depart after delivering a pivotal warning: “Your choice is simple: join us in peace or pursue your current path and face obliteration. We shall be waiting for your response.” Clearly, the alien hailed from an advanced civilization concerned about the threat of nuclear destruction on our planet. Their message was one of peace.

The first video titled "Are we alone in the universe?" explores the questions surrounding extraterrestrial life and the implications for humanity.

The second video, also titled "Are we alone in the universe?" delves into the scientific inquiries and discoveries that fuel our fascination with life beyond Earth.