New research has revealed that the world's largest radio telescope, located in China, could potentially spot self-replicating probes launched by a distant intelligent alien civilization, should they exist.
These probes, also known as von Neumann probes after the scientist who first proposed their existence, have been posited as the most efficient way for intelligent life to explore the wider Universe.
As of yet, no evidence of such a self-replicating swarm of extraterrestrial robots has ever been discovered, of course. Free University of Tbilisi, Georgia, researcher Dr. Zaza Osmanov calculates that if such swarms exist, China's Five-hundred-meter Aperture Spherical Radio Telescope (FAST) could have a chance of glimpsing them.
"The reason why von Neumann probes are very efficient in exploring the universe can be briefly explained in the following way: since they replicate, their number increases exponentially and therefore, the swarm of robots expands very rapidly," Osmanov told Newsweek. "I would characterize von Neumann Probes like a swarm of bees, but unlike normal bees replicating so rapidly that in a very short time (in cosmic scales) they can cover the whole nebula or even a galaxy."
In a paper accepted for publication in the Serbian Astronomical Journal Osmanov considers probes from civilizations that are both capable of using the total power output of their star, and those capable of using the energy output of their entire galaxy. Known respectively as Type II and Type III civilizations, both hypothetical alien societies are far more advanced than humanity.
"My calculations show that Type-II and Type-III alien societies might be able to build von Neumann probes," Osmanov said.
Osmanov suggests that these self-replicating machines would emit some form of radiation, which should be visible in the radio spectrum. That means this radiation would fall right in the middle of the spectrum that FAST has been designed to detect.
Given the sensitivity of FAST Osmanov found that the radio telescope could spot self-replicating probes from a Type II civilization at a distance of around 86,000 light-years, about 85 percent of the diameter of the Milky Way.
He calculated that such probes from a more advanced, and arguably more ancient Type III civilization could be spotted by FAST by around 13 million light-years away, well outside our galaxy.
Professor of Science at Harvard University and bestselling author of the book Extraterrestrial, Avi Leob, also believes that the FAST telescope could spot such self-replicating devices if they utilize radio waves.
Loeb told Newsweek: "FAST is sensitive to signals in the radio band and it is unclear whether extraterrestrial equipment will transmit signals in this band. There is a class of transient radio sources, called Fast Radio Bursts, whose nature is unclear. Perhaps some of them are artificial in origin."
Exploring The Universe With Self-Replicating Probes
Loeb continued by explaining why these self-replicating machines that can repair damaged parts or reproduce copies of themselves out of the raw materials they find on a distant planet would be an efficient way for civilizations to explore the Universe around them.
"The light travel time to the nearest star is four years and out to the edge of the Milky Way disk - it is tens of thousands of years. A spacecraft sent to interstellar space cannot rely on real-time guidance from its senders. It has to be autonomous and make its own decisions," the Havard scientist said. "Self-replicating probes resemble biological systems in that they lead to multiple generations, but their life could be much longer than ours. They may last millions or billions of years, a sufficient time to cross interstellar distances."
Lob believes that because of this long-lasting nature and the rapidity by which they would spread if humanity is ever to encounter an alien civilization it will be in the form of von Neumann probes.
"Biological creatures were not selected by Darwinian evolution to survive in space," Loeb explained. "Self-replicating machines can easily populate the entire Milky Way galaxy in less than a billion years. Since most stars formed billions of years before the Sun, it is possible that we already live in such a reality."
The Havard-based researcher goes on to explain that spotting such probes and other technology of an extraterrestrial nature with telescopes like FAST is part of his justification to found the Galileo Project.
"This could reveal how sophisticated their science and technology is. Perhaps we can learn from them. There is no doubt that finding extraterrestrial equipment in space will change our own aspirations in space," Loeb explains, suggesting this could include sending out our own von Neumann probes.
"I hope we will send AI astronauts to space rather than systems that require our guidance. We should regard them as our technological kids. We can train them through machine learning early on and then send them to space, just as we send our biological kids to the world after an early phase of education and mentoring," he continues. "If we ever construct them, they would serve as our longest-lasting monuments in space."
Considering if humanity could explore the solar system and beyond using self-replicating probes, Osmanov is cautious. He added: "Our civilization can achieve Type-II in approximately 3000 years if 1 percent of the annual growth of technology is maintained. Therefore, in approximately 3000 years we will be able to send such self-reproducing probes into space."
Despite the distant prospect of self-replicating probes, humanity is already experimenting with swarms of interacting probes for space exploration. In 2022, NASA's Starling mission, for instance, will use CubeSats in a low-earth orbit to demonstrate the readiness of various technologies for cooperative groups of spacecraft, also known as distributed missions, clusters, or swarms.
For Loeb, this development can't come soon enough. He believes that autonomous self-replicating probes could create a better impression of humanity to extraterrestrial intelligence than we could ourselves. He concluded: "Here's hoping that extraterrestrial scientists will discover our AI astronauts first.
"Our self-inflicted climate change and wars might be counterproductive for our claim to be counted as an intelligent species in our Milky Way galaxy."
Uncommon Knowledge
Newsweek is committed to challenging conventional wisdom and finding connections in the search for common ground.
Newsweek is committed to challenging conventional wisdom and finding connections in the search for common ground.
