A Cosmic Perspective: Searching for Aliens, Finding Ourselves
SETI Institute, Mountain View, California
Are we alone? Humans have been asking this question throughout history. We want to know where we came from, how we fit into the cosmos, and where we are going. We want to know whether there is life beyond the Earth and whether any of it is intelligent.
Since the middle of the twentieth century we have had new tools that permit us to embark on a scientific exploration to try to answer this old question. We no longer have to ask the priests and philosophers what we should believe about extraterrestrial life; we can explore and discover what's actually out there. Our tools are getting ever better. We have discovered extremophiles in the most unexpected places on this planet and we have discovered that there really are far more planets than stars out there. We haven't yet found life beyond Earth. Evidence for extraterrestrial life may turn out to be ambiguous, as illustrated by the recent debate over the claim of Phosphine in the clouds of Venus, and whether this might imply biology. Evidence for technosignatures could be less ambiguous. There is a vast amount of other potentially-habitable real estate to explore beyond our solar system, and there are many plans to do just that. The 21st century will be the century in which we will find some answers.
As we look up and look out, we are forced to see ourselves from a cosmic perspective; a perspecive that shows us as all the same, all Earthlings. This perspective is fundamental to finding a way to sustain life on Earth for the long future.