Diary of an Interstellar Voyage, Report 42
(July 23, 2023)
When my mother passed away 4.5 years ago, I visited my childhood home for the first time after it was sold to strangers. At that moment, I realized that home is not merely defined by a location in three-dimensional space but also by a period of time. After a long enough time passes, your childhood home is gone, never to be found again. The house I found was renovated beyond recognition, the neighborhood was noisier, and the chicken coop— where I collected eggs every afternoon, was not there. What I encountered was a rubble of my childhood memories. The only way to maintain a stable ride through life is to move forward steadily, just like riding a bicycle.
The same lesson applies to the ultimate fate of our home planet, the Earth. Astronomical calculations indicate that within a billion years the Sun will boil off all the oceans on Earth and life-as-we-know-it will go extinct. If a group of humans will board a space platform and then return back to Earth in a billion years, they would find a rubble of memories. The only stable way to maintain longevity is to ride forward on a spacecraft to interstellar space and never look back.
Given that most sun-like stars formed billions of years before the Sun, there must be many lost worlds out there, encapsulating tragedies of lost species and the rubbles of memories. The only long-term memorabilia left from lost technological worlds are the probes they launched to interstellar space. These probes would appear to astronomers as anomalous interstellar objects, unlike the asteroids and comets found in the solar system. If their technological expiration date had long passed, they would constitute space trash. When colliding with Earth, each of them would light-up as a meteor fireball due to its friction with air. The fireballs of technological objects can be viewed as memorial candles, each commemorating a civilization which may no longer be with us. In that case, these fireballs should be labeled as “memorial encounters of the third kind.”
The first recognition of a possible memorial candle of this kind, may have occurred on January 8, 2014, when a meteor crashed over the Pacific Ocean, about 90 kilometers away from Papua New Guinea. This first recognized interstellar meteor, IM1, was moving outside the solar system at a speed of 60 kilometers per second relative to the local standard of rest of the Milky Way, faster than 95% of all nearby stars. Moreover, IM1 had material strength tougher than all other 272 meteors in the CNEOS fireball catalog of NASA. The New Horizons spacecraft is heading towards interstellar space and could appear as our own memorial candle within billions of year, were it to collide with an exoplanet and burn-up as a meteor of unusual material strength and anomalous speed.
The interstellar expedition team is currently studying spherules, the molten droplets left over on the ocean floor from IM1’s surface, when it was exposed to the immense heat from its fireball. These were retrieved from IM1’s crash site. If IM1 was space trash from another civilization, we might see technological fingerprints of molten semiconductors or computer screens in IM1’s element composition or ratios of rare isotopes.
This week, our analysis of the expedition’s findings will be aided by Dr. Jim Lem, head of the Mining Engineering department at the University of Technology in Papua New Guinea, who just arrived for a visit to Harvard University. The visit follows an official agreement between the two universities. Shortly after his arrival, I invited Jim to join the annual soccer match of students versus faculty & postdocs in Harvard’s Institute for Theory and Computation, for which I serve as director. I gave my own Galileo expedition T-shirt as a gift for Jim for him to wear at the game.
Gladly, the faculty & postdocs team won. I was fortunate to score 7 goals, about half of my team’s total. A few middle-schoolers came over after the game to ask me if I play professional soccer. I disappointed them by admitting that I am a professor and encouraged them to study science.
The following evening, Jim and I had dinner with Professor Stein Jacobsen who recently imaged a spherule which looks like a soccer ball, and my summer intern student, Sophie Bergstrom, who is by now celebrated as the “spherule hunter” of the interstellar expedition team after discovering a total of 250 new spherules in the retrieved materials bringing the total to 420! During dinner, we made plans for Jim to get engaged with the analysis in Stein’s laboratory at Harvard in the coming days.
Whether IM1's spherules are ashes of an extinct civilization or just a rock from a natural astrophysical origin, will be vetted by state-of-the-art diagnostics in three laboratories, equipped by electron microscope imagers, X-ray fluorescence analyzers and mass spectrometers.
If a technological origin is identified for IM1’s fireball, we should cherish the moment to commemorate the senders who may not be with us anymore. This would be a sobering reminder that everything in life is temporary and we should always celebrate life-as-we-know-it while it lasts.
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 chairs the advisory board for the Breakthrough Starshot project, and 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. His new book, titled “Interstellar”, is scheduled for publication in August 2023.