By Jonas Reichert
Have you ever looked at the night sky and asked yourself if we are the only ones in this universe? Or if someone is looking back? If you did, you are not alone. This question has accompanied humanity since ancient times. Already around 300 B.C., Greek philosophers speculated about the existence of life and even intelligent beings outside Earth. Today, however, we have the technology to search the sky for signs of life.
The search for extraterrestrial intelligence (ETI) has already begun. In 1960, Frank Drake, a scientist at Cornell University, conducted the first survey for artificial radio signals. Many surveys followed, most of them privately financed. Yet, besides the WOW-Signal in 1977, a strong radio-signal, whose nature remains unclear to this day and which was considered as a possible messaging attempt, no signs of communication attempts by an ETI were detected. This motivated some researchers to choose a more active attempt by starting communication endeavours themselves. At the same time, other scientists warned of the dangers of such a project. Currently, messaging ETI is not yet realized and unlikely to succeed in the coming decades.
The prospect of receiving a message from ETI has implications for politics. A message would most likely not be addressed to one particular nation, but sent out into space in hope it will reach someone. It could be received by researchers or militaries of any country, which is lucky enough to look in the right frequency band in the right direction at the right time. There is to date no protocol how to deal with it. The question of who has the right to know and to respond is still unanswered.
But despite all the effort, no contact has yet been made. So where is everybody? One can estimate that a civilization like humanity should colonize their galaxy in a timespan of just millions of years, which from a human perspective seems long, but is just a short period in the 14 billion years of the universe’s history. If we are not the first, why are they not yet here? Many explanations were proposed over the years. They range from the zoo hypothesis, which proclaims that an ETI is already here and observes us, to pure disinterest of every advanced civilization in interstellar expansion.
The most likely, but also the most depressing, explanation is that no civilization can persist long enough. They are either destroyed by cosmic events on a regular basis or tend to destroy themselves. Whether by destruction of the environment, nuclear war or some other technology which runs out of control, humanity seems to have a good chance to prove this theory right.
But if we manage to find intelligent life, it would certainly be a revolution. The Copernican Revolution moved the Earth from the centre of the solar system. Later, scientists found that we are in a non-important part of an average galaxy which is part of a far bigger structure. Finding life outside Earth would displace the human as the only intelligent being in the universe. What follows is a cultural shock. Humans could fall in lethargy as we are not only an unimportant part of humanity, but also an unimportant species in the universe. The world will sink into war while fighting about who has the right to establish contact. A hostile civilisation would have no need to invade Earth, we would destroy ourselves.
However, this is only the negative scenario. The certainty that someone looks back if you look at the night sky can also be liberating and inspiring. And humanity may use this as an occasion to overcome hostility and rivalry. Alliances are formed to delimit yourself from others. If we there was something big outside of Earth, we might be able to shape the United States of Earth, like featured in many science fiction stories.
For now, we still don’t have any reason to believe that we could track intelligence outside of Earth. Furthermore, our universe seems to have a built-in speed limiter for communication: no information can be transmitted faster than the speed of light, which means that a message to our nearest neighbouring star Proxima Centauri would already need more than four years to arrive. This makes interstellar communication incredibly difficult. So we could either neglect the issue as a theoretical game or we could listen to the science fiction author Arthur C. Clarke: “One of the biggest roles of science fiction is to prepare people to accept the future without pain and encourage a flexibility of mind”.
The research on ETI can also provide a new view on ourselves. In an article in Acta Astronautica, Baum, Haqq-Misra and Domagal-Goldman described different scenarios for the consequences of a direct contact with other intelligent beings. Some of their scenarios are uplifting. Yet, others include that humanity could be used as a source of food or be destroyed by accident. The Earth could also be destroyed to make space for an interstellar infrastructure project or be attacked out of fear of being or becoming dangerous. Also, the ETI could bring a new, unstoppable disease or invasive species. But all this is deeply human and as happened before in human interaction and the interaction with our environment. Maybe the fear of an ETI is actually the fear of ourselves.
Illustration: Matilda Zeitz
Jonas Reichert is an exchange student from Heidelberg in the south of Germany, where he does a degree in Physics. Besides his interests in life outside Earth, he can be found on most times in debating tournaments. In Sweden he tries to figure out how to bake and how to survive the winter.