So far, humanity only explored space with robots that are operated by Earth-based commands, such as the Perseverance Rover or the Ingenuity Helicopter on Mars. `Helicopter parenting’ of this type is not a viable option for long interstellar journeys because of the long time-delay in communications even at the speed of light, the faintness of the communication signal at great distances, and the inability to transmit all of the relevant information over a reasonable time.
When engaged in interstellar travel, we will need to send out probes that can make their own decisions based on circumstances, and let these `technological-kids’ be autonomous. Just like biological kids who leave home, they will report back sporadically on highlights of their journey. Artificial Intelligence (AI) would provide the brain of these autonomous space probes.
The hardware design of these `AI-astronauts’ could be hardened to be resilient to the hazardous environment of interstellar space, so as to avoid damage from energetic particles in the form of cosmic-rays, dust particles or micrometeorites. Intelligent biological systems, like humans, were selected through Darwinian evolution to survive on Earth, protected from cosmic-rays by the Earth’s magnetosphere and having natural resources of nutrients. Humans are not suitable for survival on an artificial space platform, given the challenging conditions encountered during the millions to billions of years associated with the interstellar journeys enabled by our current propulsion technologies.
How practical is it to employ in-situ AI on space probes? The primary challenges include power supply and mass. Currently, the AI systems used on Earth are massive and require gigawatts of power. These physical requirements pose major challenges for trips far away from Earth. As of now, most of the space budget is allocated to national security and defense-related tasks in satellites close to Earth, where Earth-based AI can still be used via short communication links. Scientific space-exploration to faraway destinations is of low priority, consuming less than a percent of the global defense budget worldwide of 2.4 trillion dollars per year.
The better way to explore the Moon, Mars and beyond, is by using a swarm of small probes, each equipped with sensors that feed an in-situ AI system with data — allowing the probes to make autonomous decisions. The probes can report back essential information based on their mission. A swarm of probes can explore more real estate than a single large probe of the type that was traditionally employed by space agencies.
In analogy with dandelion seeds, one could launch self-replication systems with AI and 3D printers and without an umbilical cord that connects them to Earth. These self-replicating probes could grow in number using the raw materials they find at their destination.
In the short term, a swarm of probes could be used to survey the surface of the Moon or Mars for water ice reservoirs that could fuel local economies. Electrolysis can break water molecules to molecular hydrogen and oxygen based on sunlight-powered electricity, and use hydrogen or oxygen fuel to propel rockets or machinery. On Mars, it would be beneficial to develop special-purpose probes to survey lava tubes as habitats that protect humans and infrastructure from damage by cosmic-rays and UV radiation as well as extreme variations in temperature between day and night. The AI-equipped probes could also search for Martian life by melting ice or using microscopes to probe Martian soil after adding liquid water to it. Finally, the probes could survey Martian lava tubes for early life on Mars, including preserved wall paintings from early Martians or any ancient technological relics.
Assuming that we are not privileged and adopting the principle of reciprocity from our interstellar neighborhood, we must search for AI astronauts from other civilizations that may pass close to Earth. I summarized my thoughts on this line of research at the new episode of the Shawn Ryan Show, to be aired on October 7, 2024.
The Galileo Project research team that I lead is searching along three avenues for technological objects near Earth that may have been manufactured by alien civilizations. The first avenue involves constructing new observatories for monitoring the sky. The preliminary results from monitoring half a million objects by the first Galileo Observatory at Harvard University are being summarized in a new paper that will be shared publicly soon. In 2025, we plan to construct and operate two additional Galileo observatories in other locations. The second avenue involves searching for new interstellar objects and unidentified objects in the data pipeline of the Rubin Observatory in Chile. Finally, the third avenue is to study interstellar meteors. The millimeter-size spherules retrieved from the fireball site of the interstellar meteor, IM1, were analyzed over the past year and the findings were just published in a new detailed paper. We plan another expedition in 2025 to retrieve larger pieces from IM1’s wreckage and find out whether it was a rock or a technological gadget.
Whether we explore interstellar space with AI-equipped probes or find that other civilizations did it before us, the coming decades will be exciting. Life is worth living because the future carries the potential of being better than the past.
ABOUT THE AUTHOR
Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024.
