Alien life has long piqued our interest, but that interest has exploded with the rapidly expanding field of Extraterrestrials–Astrobiology. Do Aliens, Aka Extremophiles, Exist? Science Fiction and science communication–at least in their own ways–take most of the credit for the increased interest in science. In 1983, H. G. Wells made fun of the American audience via radio drama and later wrote his first novel, ‘The War of the Worlds.’ Since then, UFO sightings have become ridiculously common for no reason at all.
Are Aliens Real?
Before we question whether extraterrestrial intelligence exists, we must first address whether extraterrestrial life exists elsewhere and or we are alone in the universe. The simple answer is: We don’t know. As of now, our limited technology has allowed the only world we have ever set foot on be our own Moon, and the furthest planet our rovers have landed be Saturn’s moon Titan. Visibly, the very region we can freely observe for the past century has been our own Solar System, where, apart from Earth, life may not exist or may exist but not flourish like on Earth or may exist in a form we cannot recognize.
To find life elsewhere in the universe, we first have to learn what ‘Life’ is and its characteristics. Astrobiologists observe life on earth, the only known place in the Universe as of now to host life, including the conditions and the biosignatures, which provides evidence for the existence of organisms outside earth by detecting their unique byproducts. We once determined the abundance of Oxygen as a Biosignature before learning how Oxygen can be produced by non-biological methods. In September 2020, Phosphine, a potential biosignature, on Venus was determined by the ALMA telescope, but it has confirmed life on Venus. Elsewhere within our solar system, we know for sure that life is not abundant. It may either be present as microorganisms under the layers of planets thriving in extreme conditions. Therefore Astrobiologists love studying Extremophiles. But first, let’s talk about the conditions on Mars, the protagonist in War of the Worlds, and the most popular candidate to host life.
The possibility of life on Mars is of tremendous interest in Astrobiology because of its similarity to early earth, yet, until now, they have found no evidence of life on Mars. Several findings show that ancient Mars hosted liquid water and may have held water-based life forms but may have either died out or migrated to the sub surfaces. However, habitability not shows life. Because of the present Mars’ extreme conditions in terms of atmospheric pressure and temperature UV radiation, scientists study the extents to which life on earth can withhold via extremophiles to determine the threshold of habitability.
Extremophiles are also an answer to how life survived over three billion years on earth and the adaptation it needed. Biological systems only function in certain physical and chemical extremes. As we approach these extremes, life’s diversity gradually diminishes, so there should be a chemical and physical limit beyond which life cannot thrive. The study of earth organisms at these extremes reveals how life has developed on Earth and whether life can handle extreme environments on alien planets.
There are several extreme environments, hot or cold, salty or dry, alkaline or acidic, and places subject to extreme pressure and radiation. These are the environments most commonly found on the surfaces of the planets within our solar system.
For example, the analogous deserts on Antarctica host similar conditions to those on Mars. In Antarctica, the discovery of microorganisms under the surface might suggest similar microbes survive under the surface of Mars.
The Goldilocks zone is the ideal place for carbon- and water-based life to merge and flourish. Unfortunately, the Goldilocks of our solar system have already been occupied, and we may not find life similar to our own elsewhere in our solar system. We are looking for microbes that are thriving in extreme conditions, far from being intelligent. Our technology still does not allow us to observe Earth’s 2.0s outside our solar system, so we’re probably a long way from getting in touch with an advanced civilization that may bring us surprises of many kinds. Extremophiles are the closest thing to finding out whether we are alone in the Universe.