Of Aliens and Astrobiology
It may sound far-removed from reality, but astrobiology or the branch of biology concerned with the study of life on earth and in space, is actually quite practical. Though this field is relatively new compared to the long-established fields of astronomy, biology, physics, geology and planetary science, astrobiology is essential for securing the future of humans. That’s because it combines the search for habitable environments in the solar system and beyond while researching the evolution and adaptability of life here on Earth. Astrobiology seeks to answer fundamental scientific questions about life—including the conditions for it to flourish here or elsewhere in the galaxy.
Meet Earth, Our Planet
The oldest known fossils found on Earth are around 3.5 billion years old, 14 times the age of the oldest dinosaurs. Different theories and beliefs have sprouted on how life on Earth began. Before the 1800s, most people believed in “vitalism”, an idea that living things were endowed with a special, magical property that made them different from inanimate objects.
Another famous theory is Charles Darwin’s Origin of Species, which explains how the vast diversity of life could all have risen from a single common ancestor. Instead of each of the different species being created individually by God, the theory poses that all descended from a primordial organism that lived millions of years ago.
Earth is often referred to as a “Goldilocks planet”. Like the third of the three bowls of porridge in the fairy tale Goldilocks, it is neither too hot nor too cold, but just right. This allows liquid water—which is essential to life— to flourish in our planet. But do you know that the Earth hasn’t always carried water? A theory suggests that asteroids struck the Earth, carrying this life-giving substance and other bacteria to our planet.
It is a fact that humans are outnumbered by bacteria. As Evolutionary Biologist Stephen Jay Gould wrote, “Our planet has always been in the ‘Age of Bacteria’ ever since the first fossils bacteria, of course, were entombed in rocks more than 3 billion years ago. On any possible, reasonable or fair criterion, bacteria are and always have been the dominant forms of life on Earth.”
A journal published online by the University of California Berkeley on April 11, 2016 reinforces that humans represent only a tiny percentage of the world’s biodiversity.
Life on Mars?
Martians or inhabitants of the planet Mars have long been the subject of pop culture, whether in jest or all seriousness. But recent explorations in Mars have found water bound in the fine soil of the “Red Planet”, particularly in the Gale Crater. This crater was created when a large meteor struck the planet 3.5 billion to 3.8 billion years ago. They discovered that Mount Sharp, a mound of rock in the middle of Gale Crater, was built by sediments deposited in a large lake bed, tens of millions of years ago. Experts believe that the crater itself was once a vast ocean. An analysis of rocks at the bottom of a mountain in the middle of the crater shows that water flowed at different levels over the course of millions of years. In fact, there are still substantial amounts of ice water at the Martian poles.
The mission of Curiosity, a car-sized rover that’s part of NASA’s Mars Science Laboratory mission (MSL), includes investigating Martian climate and geology, assessing whether the Gale Crater has ever offered environmental conditions favorable for microbial life, including the investigation of the role of water, and planetary habitability studies in preparation for future human exploration.
The question of whether there is, or was, life on Mars may finally be answered by the European Space Agency’s ExoMars mission, which will land a 300-kilogram rover on the Red Planet in 2019.
Chances of life beyond Earth
We assume that one-fifth of all stars have habitable planets in orbit around them. This leads us to conclude that there should be other advanced technological civilizations out there. In our very own Milky Way galaxy, the odds of being the only technologically advanced civilization are 1 in 60 billion. Thus, it’s very likely that other intelligent, technologically advanced species have evolved before us.
According to the History Channel, Frank Drake a notable astronomer, created an equation that was able to “estimate the likelihood of the existence of alien life, taking into account a number of factors including the average number of planets able to support life and the fraction that could go on to support intelligent life.” The equation found that “hundreds of thousands” of planets that could support extraterrestrial beings could and should exist.
So… do aliens really exist? This question has baffled humans ever since prehistoric man noticed the bright stars in our sky. Thousands of paranormal sightings have been recorded on video since then, with many conspiracy theories and fictional films such as E.T. and Alien generating much interest among UFO hunters. Hundreds of pictures and videos of UFOs are taken every year. While some have been debunked as fake, there are still dozens that have left even the experts scratching their heads and wondering if we really have been visited by creatures from another planet.
According to the Telegraph, Charles Bolden, administrator of the National Aeronautics and Space Administration (NASA) was quoted: “I do believe that we will someday find other forms of life or a form of life, if not in our solar system then in some of the other solar systems — the billions of solar systems in the universe.”
As technology advances, our research probability also expands. If extra-terrestrial life exists, then perhaps, life on Earth can also exist in other planets. Rather than being a scary thought, aliens now give us hope—that we are not alone, and that with the gradual degradation of our planet, human life can still thrive elsewhere. Such is the possibility astrobiologists are now endeavoring to find out.
By Panahon TV Intern Patrick Obsuna
Of Aliens and Astrobiology