Can Interstellar Meteors Help to Design the Heat Shield for Musk’s Starship?
Arriving at Berlin, Germany, felt like visiting an alien civilization. The day before that, I gave the opening lecture in a conference at Thessaloniki, Greece to a room full of cosmologists. After 24 hours, I was scheduled to give a lecture in Berlin to an audience of Tech entrepreneurs at the TOA 2024 Tech and Startup Event.
As I entered the brightly-lit stage of the Colosseum cinema in East Berlin, I told the audience: “I ask you to imagine young and creative entrepreneurs like yourself, born on the other side of the Milky-Way galaxy near a star that formed a billion years before the Sun. Their Starships could have arrived near Earth by now.” I then went on to describe the Galileo Project’s search for these objects.
As soon as I finished speaking, I was approached by an inspiring reporter, Matthias Bieder, who came to interview me. At the end of our conversation, Matthias asked me to autograph a copy of the German translation of my book, “Extraterrestrial,” for his young children, Julius and Paulina, whose names were selected to accompany a poem by the U.S. Poet Laureate Ada Limón’s “In Praise of Mystery: A Poem for Europa,” as a message in a bottle on the upcoming Europa Clipper mission of NASA. I told Mattias that I hope this selection will convince Julius and Paulina to become astrophysicists. In my autographed note, I wished them to be the discoverers of our cosmic neighbors.
As I went down the hall, I was stopped by audience members who asked me to sign other copies of my book and by an artist who was particularly excited by my lecture. The photographer who accompanied Matthias noted calmly: “You are a rock star.”
The audience in the two conferences could not have been more different from each other. The first community was concerned with the evolution of dark matter and dark energy — as shaped by cosmic inflation, whereas the second community was focused on the evolution of technological innovations — as shaped by financial inflation. But my interactions with both of them convinced me that there is an important way by which the two complementary communities could pollinate each other.
The Nobel laureate, Steven Weinberg, argued towards the end of his book titled `The First Three Minutes’: “The more the Universe seems comprehensible, the more it also seems pointless.” I told the young Berlin entrepreneurs what they already know from their private life: since finding a partner gives a meaning to our existence on Earth, finding that we are not alone beyond Earth will make the universe meaningful for us. Once this discovery is made, Steven Weinberg and his followers at the cosmology conference in Thessaloniki, will have to admit that the universe is not pointless. When Enrico Fermi asked “Where is everybody?” in 1950, he did not search for partners but was waiting for them to show up at lunchtime in Los Alamos. Our civilization feels lonely because it does not invest billions of dollars in the search for meaningful partners. Instead, the mainstream of astrobiology engages in the search for extraterrestrial microbes. I am sorry to break the disappointing news, but microbes will not be able to carry a meaningful conversation with us on our first date. It is arrogant to dream that we will find intelligent counterparts without searching for them, just because they find us attractive.
Thinking outside the box, the way Tech entrepreneurs do, might bring the spark that will ignite the most important discovery of all times in science: extraterrestrial intelligence.
Shortly after my arrival at Berlin, I received an email from the brilliant Dr. Robert Cykiert M.D., who interviewed me on his podcast recently. Robert asked: “Are the spherules of the interstellar meteor IM1 made of an alloy that is more heat and pressure resistant than other earthly alloys or alloys found in solar system meteorites? If so, can the alloy be used as a heat shield for Elon Musk’s Starship? Musk has frequently emphasized that an effective heat shield for Starship is difficult to make, and the stability and effectiveness of the heat shield is one of the main tests of the next Starship flight tomorrow.”
I replied that indeed the material strength of IM1 was unprecedented among all previously known meteors from the solar system, since IM1 maintained its integrity down to the low atmosphere at an altitude of 19 kilometers, despite its high speed. In comparison, the recent meteor over Spain and Portugal on May 18, 2024, had a similar entry speed of about 40 kilometers per second but exploded at an altitude of 74 kilometers, where the air density is a thousand times lower than at the explosion altitude of IM1. This implies that the yield material strength of IM1 was a thousand times higher and tougher than all known iron meteorites.
The spherules that we recovered in our Pacific Ocean expedition to the IM1 fireball site in June 2023 exhibited a unique chemical composition, labeled “BeLaU” in our analysis paper. However, these “BeLaU”-type spherules are less than a millimeter in size and lost their volatile elements during the meteor’s explosion. This does not allow us to reconstruct the full elemental composition of IM1 or reconstruct its unique material properties. The next Galileo Project expedition, will attempt to recover bigger pieces that include the full material and solid-state structure of IM1. It would be amazing if the pieces that our next expedition might recover will help Elon’s team in their effort to improve the design of Starship’s heat shield.
Bigger pieces of IM1 will enable a complete laboratory analysis of their material strength and thermal conduction properties. Irrespective of whether IM1 was artificial or natural in origin, its material properties can provide new insights into the optimal design of the heat shield for Starship. In case IM1 was a technological probe, its senders might have incorporated material design beyond our technological knowledge. In the case of a natural origin, like the spaghettification of a magma-ocean planet, nature may have gifted us with a unique preparation process that we can reproduce in our laboratories.
Can astronomy help space entrepreneurship on Earth? In tomorrow’s launch, Starship will first (fingers crossed!) move through the Earth’s atmosphere in the opposite direction to that taken by the interstellar meteors IM1. The material physics that allowed IM1 to survive at a much higher speed than that of Starship, could help us visit alien worlds.
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. His new book, titled “Interstellar”, was published in August 2023.
