Nov 15, 2022 I Paul Seaburn

NASA Study Says We May Be Alone in the Universe Because of the "Great Filter"

Anyone involved with or even just interested in the search for extraterrestrial life inevitably runs up against the wall known as the Fermi paradox. During a casual conversation about UFOs with fellow physicists in the 1950s, Enrico Fermi, the creator of the world's first nuclear reactor, listened to arguments that the universe should be teeming with life since the Milky Way galaxy alone has billions of stars with the potential to have generated life in the same manner as it happened on Earth, but billions of years ago … giving that life time to become much more advanced and capable of travel around the universe. Fermi immortalized his name one more time by pondering the proposal and then asking the question (paraphrased): "If there is so much life around … where is everybody?" Many scientists have tried to resolve the Fermi paradox. One of the more recent arguments against the Fermi paradox is called Great Filter – a nearly impenetrable wall that is blocking life everywhere from advancing to the space travel level. That theory just got a boost from an unlikely source – NASA. Why would NASA – an organization with the mission to look for life on other planets – suddenly accept a theory that could put it out of business? What would Fermi think?

Is that them?

Consider our best-guess evolutionary path to an explosion which leads to visible colonization of most of the visible universe:

  • The right star system (including organics)
  • Reproductive something (e.g. RNA)
  • Simple (prokaryotic) single-cell life
  • Complex (archaeatic & eukaryotic) single-cell life
  • Sexual reproduction
  • Multi-cell life
  • Tool-using animals with big brains
  • Where we are now
  • Colonization explosion

According to the above list from Robin Hanson’s 1998 paper, “The Great Filter - Are We Almost Past It?”, it ain’t easy being alive. To get to the advanced level where it is capable of colonizing other planets, Hanson proposes a fast explosion of development is required. The explosive expansion must be fast enough to outpace an event that could stop it completely – like a supernova – or an invasion by another species whose explosive advancement put them in a more powerful position. Hanson, an economist, takes a probability approach to solving the paradox. Perhaps advanced life doesn’t exist because the probability is so low. But what about the search for signs of ANY kind of life? We haven’t found that either. Hanson takes his probability argument back to the beginning of life – abiogenesis, the ability of life to rise from lifeless chemistry. Perhaps Earth is the only winner in the abiogenesis lottery. Or perhaps Earth is the only place where an abiogenic life advanced beyond the single cell or bacterial stage.

Assuming a planet is able to give life the probability to advance past the multi-cell stage, it must then reach the tool-making stage. At this point, it needs a technological explosion.

“Similarly, technological "optimists" have taken standard economic trends and our standard understanding of evolutionary processes to argue the plausibility of the story I gave above, that our descendants have a decent chance of colonizing our solar system and then, with increasingly fast and reliable technologies of space travel, colonizing other stars and galaxies.”

In other words, an advanced civilization must advance past the “NASA” stage where we humans currently are. This is where a team from NASA’s Jet Propulsion Lab comes in. Led by JPL astrophysicist Jonathan Jiang, they attempt to identify the Great Filter and then figure out a way to penetrate it – either as humans or as another advanced species on another planet.

“The key to humanity successfully traversing such a universal filter is… identifying those attributes in ourselves and neutralizing them in advance.”

JPL astrophysicist Jonathan Jiang led the study, published online and not yet peer-reviewed. In a sense, they look at the Great Filter as a great destruction event which stops all advancement cold. That could be a natural event, such as a massive asteroid like the dinosaur-killing Chicxulub impact event. Unfortunately, all of the rest of the ‘filters’ they came up with are unnatural self-inflicted events.

“Human civilization over the past 5000+ years, and in particular since 1945, has revealed much of what would surlily impede, if not outright arrest, our aspirations to colonize other worlds in the Solar System and beyond. It seems as though nearly every great discovery or invention, while pushing back the borders of our technological ignorance, is all too quickly and easily turned to destructive ends. Examples such as splitting the atom, biomedical innovations and resource extraction and consumption come to mind with disconcerting swiftness. Still, some have suggested artificial intelligence (AI) as yet another factor which, pending substantial technical hurdles, may yet have its chance to prove friend or foe.”

Is it possible that no civilization in the galaxy, let alone the universe, can get to space travel without using the technology to self-destruct first? Or is it possible that no civilization can advance fast enough to outpace or stop a natural destruction event such as an asteroid collision? The answer is ‘yes’ to both, according to the study. Are they just possible or are they inevitable? That is where NASA saves its job by laying out an anti-dystopian but not necessarily plausible plan for humanity to break through the Great Filter.

“The foundation for many of our possible filters finds its roots in immaturity.”

“Immaturity” is too nice of a word for this study’s definition of the components of Great Filter: “And yet, we prolong notions that seem to be the antithesis of long-term sustainable growth. Racism, genocide, inequity, sabotage… the list sprawls.” To surmount those blocks requires massive changes to entire cultures which have endured for centuries, dismantling nuclear and other weapons of mass destruction, focus on ending diseases and controlling viruses, develop technology to stop an asteroid, implement more efficient forms of energy generation … as the study says, the list sprawls.

“History has shown that intraspecies competition and, more importantly, collaboration, has led us towards the highest peaks of invention.”

This is where the NASA study and Robin Hanson’s idea of the Great Filter diverge. As the Daily Beast points out, the study supports a centralized control of changing culture, science and government to form a cooperative world that can avoid self-destruction. On the other hand, Hanson sees decentralization as the key – while joining hands and pooling minds and resources is good, small groups would be better for surviving catastrophes like asteroids or pandemics or wars.

Do we have to get along in order to find other advanced civilizations?

Seth Shostak, an astronomer with the California-based SETI Institute, says in the Daily Beast article that the NASA study has one big hole in it … it assumes there is no advanced species out there and then works backwards to explain why. Perhaps we just can’t see far enough away. We’re all in awe of how the James Web Space Telescope has shown us more galaxies. Now we need an equivalent telescope to narrow the focus on those galaxies – and on the millions of solar systems in the Milky Way – in order to find signs of those advanced species.

Fermi asked, “Where are they?” NASA’s Great Filter study says they’re too primitive to see. If “they” exist and are looking for us … what are “they” thinking?

Paul Seaburn

Paul Seaburn is the editor at Mysterious Universe and its most prolific writer. He’s written for TV shows such as "The Tonight Show", "Politically Incorrect" and an award-winning children’s program. He's been published in “The New York Times" and "Huffington Post” and has co-authored numerous collections of trivia, puzzles and humor. His “What in the World!” podcast is a fun look at the latest weird and paranormal news, strange sports stories and odd trivia. Paul likes to add a bit of humor to each MU post he crafts. After all, the mysterious doesn't always have to be serious.

Join MU Plus+ and get exclusive shows and extensions & much more! Subscribe Today!