SETI is an acronym for the Search for Extraterrestrial Intelligence. It’s the kind of name that upon mention prompts a spontaneous string of questions and theories. However obscure your question, the extensive¬†FAQ section on the SETI Institute website¬†is where you’re likely to find the answer. There’s no frequently asked questions list quite like it. Where else would “What would it be like to be at the bottom of the atmosphere of a gas giant planet?” be considered a pressing inquiry? In case you’d like to know the answer to that:¬†Giant planets do not have a solid surface that you could stand on. If you were dropped on Jupiter for example, you would sink until crushed by the intense atmospheric pressure.
Is someone hiding aliens?
We don‚Äôt think so.
What happens if you detect a signal?
Once an artificial signal is confirmed as being of extraterrestrial intelligent origin, the discovery will be announced as quickly and as widely as possible. There will be no secrecy, and indeed getting the word out quickly is important as there would be an urgent need to have astronomers world-wide monitor any detected signal, 24 hours a day.
Accepting the green-skinned look as a storyteller’s invention, it’s a shared curiosity to wonder how exactly these beings would, well, be.
Seth Shostak¬†is the Senior Astronomer at SETI. According to his highly educated estimate, any society we discover will be way more advanced than ours. If you take into account the age of the universe, they could be millions of years older than humanity. Their detection could bring with it a confirmation that we’re not inevitably doomed to our current self-destruction.¬†If they were able to survive their technology then maybe we could survive ours.
Their potential age gives us a few more hypothetical clues. An article for Huffington Post that Shostak co-authored with Susan Schneider says that it is likely that, “most advanced alien civilizations will be a special kind of artificial intelligence (‚ÄúA.I.‚Äù) called ‚Äúsuperintelligence‚Äù – synthetic cognition that vastly exceeds the best that humans can manage in every category: social skills, general wisdom, scientific creativity, and so on.”
Using humanity as a benchmark, co-founder of the¬†Center for SETI Research,¬†Jill Tarter believes this means that an advanced alien society would be peaceful. “We’re kinder and gentler than we’ve ever been in the past,” Tarter told Business Insider.¬†The theory is that given more years we’d continue on this peaceful trajectory toward problem-solving and the ultimate survival of our species and therefore this would be an evolutionary trend for an intelligent alien civilisation too.
As for what a detection might mean for humanity, Tarter wonders if this could inspire a unification of Earth’s people to identify as one human race.¬†Shostak believes a discovery would calibrate us; we’d know we’re not alone.
SETI hasn’t heard anything yet. But if you chat to Shostak he’ll bet you a coffee that they’ll detect a signal within the next two dozen years. In which case these are questions worth asking. Shostak kindly answered some of ours.
“They are likely to be thinking machines.”
You‚Äôve said before that you believe we‚Äôll find extraterrestrial life in the next two dozen years. Why this estimate?
Thanks to accelerating improvements in digital electronics ‚Äì which is to say, computers ‚Äì we will be able to examine roughly a million star systems with our radio telescopes in the next two dozen years. Personally, I think that‚Äôs the right number to book success. It‚Äôs also the case that within that time, we‚Äôll have space probes that might find microscopic life on Mars or on some of the more promising moons of Jupiter and Saturn.
How do you imagine the discovery of intelligent extraterrestrial life would change the way we think about ourselves?
I think that the principal change would be philosophical. Any aliens we‚Äôre likely to uncover will be hundreds or thousands of light-years‚Äô distant. We‚Äôre not going to meet, and even exchanging messages may be impractical or impossible. We would know we‚Äôre not the only game in town, but that will be like knowing that the Earth goes around the Sun in Copernicus‚Äô time: incredibly interesting, but daily life would likely not change.
Do you believe we‚Äôre ready to have our perceptions changed?
Most people in advanced societies are already quite sure that we have cosmic company. They see them on TV and in the movies on a regular basis. So they will be intrigued, but not terribly surprised our horrified to learn of evidence for extraterrestrials.
Do you have faith that the right decisions would be made if there is a discovery?
I don‚Äôt know that there will be many decisions that could be classified as ‚Äúwrong‚Äù ones! Of course we would press the search for a ‚Äúmessage‚Äù in any signal we might find, and that would require spending money to build larger, more sensitive telescopes. I think that‚Äôs inevitable. Some people will want to send a ‚Äúreply‚Äù ‚Äì others may think that‚Äôs dangerous, but I doubt that it is. We‚Äôre already broadcasting our presence with our high-powered radars.
You‚Äôve said that if we were to pick up a signal, it would be from a society that is substantially more advanced than we are. What can this tell us about them?
They would be more advanced because they would need to be able to build powerful radio transmitters or lasers to produce a signal we could detect. They might be hundreds, thousands, or millions of years more technically advanced than Homo sapiens. To me, that means that they‚Äôve already transcended biological intelligence, and are likely to be thinking machines.
Could the predictions for human evolution: post-biology, genetic engineering and artificial intelligence, give us clues to how more advanced extraterrestrials might look?
We ourselves are within 50 or 100 years of ‚Äúinventing our successors‚Äù ‚Äì thinking machines. Any society we detect is very likely to have already done that, but it doesn‚Äôt tell us much about what they would look like! That would be like asking Alexander Graham Bell what phones would look like 120 years after he invented one.
Rather than sending out signals, SETI focusses on listening. Does that mean if we hear something it is from a society who is actively sending out signals to be found? What might their reasons be to communicate?
We have no idea what might motivate aliens to send signals in our direction, although the presence of oxygen in Earth‚Äôs atmosphere is a clue that life exists on this planet, and that might be an incentive. Alternatively, we might pick up signals that weren‚Äôt really transmitted for our benefit ‚Äì so-called leakage transmissions from another society.
What questions do you ask yourself which drive you to keep searching?
I think the question is very straightforward: How special is a species that‚Äôs intelligent enough to ask itself questions? I‚Äôm also driven by the relentlessly increasing speed of our searches.
How does working with the daily reminder of how small we really are impact the way you live your life?
I don‚Äôt think it affects my daily life in very noticeable ways, any more than nineteenth-century astronomers‚Äô lives were affected by learning how far the stars are. But it gives you some perspective to know that our world is truly little more than a dust mote in an incredibly vast arena.
Seth Shostak is the host of the Big Picture Science radio show and the author of a number of books, his latest being¬†Confessions of an Alien Hunter. In 2015 he was the recipient of the Carl Sagan Prize for Science Popularisation.