Could we find life outside the habitable zone of a galaxy, how could this information help our understanding of life?

Introduction

This question has always intrigued me, as soon as I learned what a “Goldilocks Zone” I was curious whether limiting our research to a specific area of a galaxy was a good idea. Was there life out there that we are not finding because we look for specific requirements in planets? Of course, at the time I did not understand how difficult it is to check a planet for life forms while we are stuck on Earth. Even though we have not found other life forms yet, I believe we could find them someday in the future.

What is the habitable Zone and why do we limit ourselves to this area?

The habitable zone is the region around a star where the temperature is just right for water to be liquid. The habitable zone of a star depends on the luminosity of the star, hotter stars have wider zones while dimmer stars tend to have thinner zones. Usually, we only look for life in planets that are in this habitable zone because we are using Earth as a blueprint to find extraterrestrial life. We use Earth as a blueprint because Earth has housed life for roughly 3.5 billion years so we can assume Earth is a prime example of a life-bearing planet. It is necessary to limit the planets we search for, that is why we use this method, otherwise, it would take much longer to find life because of all the impossibly livable planets.

Could life exist outside this zone?

In theory, yes. As with any life in space, we do not have much information, so our best bet is to make an educated guess. If a planet were to have the perfect conditions outside the habitable zone, it could house water. But what if extraterrestrial life does not need water, if this were the case it would open so many possibilities to so many planets to containing life. Currently, we do not know of any life forms on earth that do not require water to live but there is a slim chance we could find a living being who does not require the same necessities that organisms on Earth require. A good example of life that could live on other planets could be like our extremophiles. Extremophiles have evolved in such a way that they can survive in the most extreme temperatures. Theoretically, if we could find an organism that does not require water we could leave the habitable zone, and if we find an organism that does not need water and can live in extreme temperatures, like extremophiles, then we can go even further out and find the life that we did not even know could exist.

Video on extremophiles:

How does this information help us?

With this information, we would be able to maybe study these theoretical organisms and figure out how their bodies are able to survive without water and we could apply it to ourselves if we have the technology. As of now our definition of life is defined as an organism that can eat, breathe, move, grow, and reproduce. How would finding these organisms change this definition, what if these extraterrestrial life forms do not grow or maybe they do not breathe, our current view of life would be thrown out the window. Finding other life forms could help us understand how extraterrestrial life forms and Earth life forms evolve. The human body is not the most optimized organism, our bipedal bodies are not made for surviving rough areas, some have linked having free hands to tool use and can therefore also be linked to having intelligence. If we were to find intelligent life in the universe would they be bipedal for free hands or would evolution prefer them to be quadruped and have more optimized bodies for survival, could they potentially be in-between and walk on their knuckles like monkeys, knowing this could help to learn more about how evolution picks and chooses certain traits and enhances them or how the environment decides how life lives.