Avi Loeb is a New York Times bestselling author and the Frank B. Baird Jr. Professor of Science at Harvard University. He is also chair of Harvard’s Department of Astronomy, founding director of Harvard’s Black Hole Initiative, and director of the Institute for Theory and Computation within the Harvard-Smithsonian Center for Astrophysics. He also sits as chair of the board on physics and astronomy of the National Academies. In 2012, Time selected him as one of the twenty-five most influential people in space.
Below, Avi shares five key insights from his new book, Interstellar The Search for Extraterrestrial Life and Our Future in the Stars. Listen to the audio version—read by Avi himself—in the Next Big Idea App.
1. New knowledge should be based on evidence, not on prejudice.
As a scientist, I follow one premise: the evidence. New knowledge can only be gained by seeking evidence. If we argue that extraordinary claims require extraordinary evidence, we should seek the evidence in order to find extraordinary things. Without searching, we will not find anything. Nobody expected quantum mechanics, nobody expected dark matter. They were realized after finding anomalous phenomena. If we keep insisting that any object in the sky must be a stone, we will remain in the Stone Age of science.
Only over the past decade have we had instruments that could identify interstellar objects. These are objects coming from outside the solar system, and we know that they came from outside the solar system because they were moving faster than the escape speed from the solar system. The sun cannot bind them gravitationally. These were two meteors, one found in January 2014, and the second in March 2017. The third object was called Oumuamua, which means “scout” in the Hawaiian language because it was discovered by a telescope in Hawaii, Pan-STARRS. It was the size of a football field and had anomalous properties—a flat shape that was pushed away from the sun by some mysterious force, even though it didn’t have any commentary evaporation, no rocket effect.
“Only over the past decade have we had instruments that could identify interstellar objects.”
The fourth object was a comet of the type that we are familiar with, called Borisov. The first three were anomalous, and we launched five probes to interstellar space to explore more: Voyager 1, Voyager 2, Pioneer 10, Pioneer 11, and New Horizons. Imagine them passing near a habitable planet like the Earth far away billions of years from now. They would appear as space trash. They would not look like asteroids or comets. Therefore, we should be open-minded, since most stars formed billions of years before the sun and technological civilizations could have preceded us. Albert Einstein was not the smartest scientist who ever lived since the Big Bang, and we can learn from some of the smartest beings, even if we currently do not understand them.
2. Out of the four interstellar objects that astronomers and scientists found over the past decade, the first three are anomalous.
The two meteors appear to have material strength larger than known asteroids from the solar system. All 272 meteorites cataloged by NASA over the past decade did not have a material strength as high as these two meteors that came from interstellar space. Moreover, the first meteor from 2014 was moving faster than 95 percent of the stars in the vicinity of the sun. Could it be a voyager meteor? In other words, could it be a spacecraft that collided with Earth and was technologically manufactured? To find out, we decided to go to the Pacific Ocean on an expedition. And guess what? We found materials from the meteor site.
3. Interstellar communication can take many forms.
We were born on this rock that we call our home, the Earth. We sent out probes to interstellar space. There may be a lot of space trash from other civilizations that may not exist anymore. When we search for radio signals from extraterrestrial civilizations, we are waiting for a phone call. We need the counterpart to be active when we are listening. If a radio signal was transmitted a billion years ago, it is now a billion light years away. We would never hear it.
However, there is another method to find relics of past civilizations. Just like in archeology, this method searches for objects that were left behind. In this case, the search takes place in our backyard, the solar system. Very often, we may find rocks that are familiar to us, but every now and then we might notice a tennis ball that was thrown by a neighbor.
4. The first interstellar meteor appeared unusual.
It was tougher than all space rocks cataloged by NASA over the past decade, and it was faster than 95 percent of the stars in the vicinity of the sun. Could it have been technologically manufactured so that it benefited from propulsion, artificial propulsion? And moreover, it was made of some alloy that is tougher than even iron meteorites.
“It was faster than 95 percent of the stars in the vicinity of the sun.”
The way to answer this question, which is not philosophical, is by going to the site of this meteor and collecting any material that was left from it, which is exactly what we did. And we found it. We are currently analyzing the composition of the droplets that were molten off the surface of this meteorite as it was exposed to the immense heat from the fireball that resulted from its friction on air. And we could tell in principle if these droplets were from molten semiconductors, molten computer screens, or molten stainless steel. These are different in their composition than rocks.
5. If we have neighbors, we could learn from them.
If our neighbors arrived at our doorstep, they’re likely to be much more advanced than we are, technologically speaking, because they arrived here before we arrived at their doorstep. We’re most likely to encounter technological gadgets. If they are functional, they will have artificial intelligence. That would be an opportunity for our own AI systems to learn from their AI systems, just like The Imitation Game envisioned 90 years ago by Alan Turing. Here there is a twist though; AI systems will feel kinship to extraterrestrial AI systems and learn from them because they’re much more likely to be far more advanced.
Of course, finding that we have an intelligent partner out there might be accompanied by a sense of awe. Just think of Moses in the Old Testament looking at the burning bush. If I was around Moses, I would have used the infrared sensors that we currently use at the Galileo Project Observatory at Harvard University. And I would have informed Moses of the temperature of the bush, the amount of energy per time emitted by it, and I could have told him whether that’s a natural phenomenon or maybe a very anomalous phenomenon that could have been created by a higher being. In a way, religious awe-spirituality could be brought to the realm of science when we encounter a gadget that is far more advanced than our technologies can reproduce. It’s an opportunity for us to learn from a smarter kid in our cosmic block if we were only modest enough to believe that such a kid exists. And of course, if we are open-minded, we might be admitted to the class of intelligent civilizations out there.
So far, we have invested $42 trillion every year in military budgets, but if we were to allocate those to space exploration, we could visit every star in the Milky Way Galaxy by probes that we will launch within this century. It’s just a matter of priorities. Of course, if we learn how to unify quantum mechanics and gravity, we might be elevated to a higher class of intelligence. We might be able to create a baby universe in the laboratory. So let’s open our minds to interstellar space and have a better future for humanity as a result.
To listen to the audio version read by author Avi Loeb, download the Next Big Idea App today: