The State of the Universe

Avi Loeb
5 min readApr 23, 2023

Imagine President Biden delivering a State of the Union address with a supplementary comment about the State of the Universe that surrounds the Union. It is hard to imagine it given the focus of politics on issues that affect re-election on a four-year timescale, causing politicians to ignore cosmic events that take billions of years. This sentiment echoes the way we live our lives while ignoring the `elephant in the room’, our inevitable death in the long run. It is also the mindset that allows environmentalists to focus on climate change in the short term, while ignoring the ultimate astronomical fate that irrespective of how clean our energy will be - the Sun will brighten-up and boil off all oceans on Earth within a billion years.

The latest major update about the state of the universe was delivered by cosmologists decades ago. Naively, one would expect the cosmic expansion to have slowed down over time because of the gravitational attraction of cosmic matter. This follows the observation that a ball thrown up slows down over time on its way up. Gravity is attractive, as Isaac Newton concluded while watching an apple fall down to the ground in his family’s orchard. But Albert Einstein suggested a quarter of a millennium later that gravity is the curvature of spacetime and need not be attractive. He was inspired by the insight of Galileo Galilei that all objects fall the same way under the influence of gravity. This “Equivalence Principle” was confirmed by Commander David Scott who at the end of the last Apollo 15 Moon walk dropped a geologic hammer and a feather, which fell at exactly the same rate. Einstein’s equations imply that a positive energy density of the vacuum, the so-called Cosmological Constant, induces gravitational repulsion. Then came the observation to which the Physics Nobel Prize was awarded in 2011, that the cosmic expansion accelerates, implying that the vacuum is the largest component in the present-day mass budget of the Universe. But as much as this cosmic breaking news is startling with major implications for our long-term future, President Obama — a science advocate — still chose not to mention it in his State of the Union addresses. Once again, the long timescale involved in cosmology pushes any such realization to the bottom of the presidential attention span.

There is no doubt that astronomy will gain more visibility if humanity branches out to have sustainable communities of people on the Moon, Mars or beyond. The trade relations with remote communities will deserve economic attention and the value of extraterrestrial assets will require the attention of the defense and intelligence agencies. We will need to worry about damage from asteroid impacts not only near Earth but also near the Moon, Mars and beyond. Space will enter prominently the State of the Union address when a substantial population from the Union will be out there.

But this slow-moving evolution will change abruptly if we discover technological products of an extraterrestrial civilization in the solar system. Consider the Webb space telescope obtaining a high-resolution image of an interstellar object observed after an alert from the Rubin Observatory, which shows metallic tiles and a giant label “Made by SpaceY on Exoplanet Z.” Since both the Webb and Rubin observatories, a million miles apart, were funded by the federal agencies NASA and NSF, the White House will be notified. However, scientific knowledge about the cosmos should not be privy to the President of the United States but instead shared with all humans

This is the rationale of the Galileo Project in search for anomalous objects near Earth that may have been manufactured by an extraterrestrial technological civilization. Yesterday, I calculated that observing the thermal infrared emission from an `Oumuamua-like interstellar object with the Webb telescope in combination with the reflected sunlight from the object by an Earth-based telescope, could allow us to map the three-dimensional structure of the object.

Survival of the fittest in interstellar space requires adaptation to the cosmic neighborhood. The longevity of the human species will not only depend on how well it mitigates existential risks from a nuclear war in Ukraine or unintended consequences from GPT-5 within the 4-year election cycle, but also on whether we venture to interstellar space, as outlined in my forthcoming book, Interstellar.

Even if we delay the instant gratification from Elon Musk’s vision of “Making Humans a Multi-Planetary Species”, we should check whether there are any packages from cosmic neighbors in the backyard of the inner solar system.

Without searching, we will not find anything. Paraphrasing John F. Kennedy’s speech at Rice University: “The Galileo Project chooses to search for our cosmic neighbors in this decade, not because it is easy but because it is hard.” Expressing an opinion or a wish is easy. Using state-of-the-art cameras and telescopes to find extraterrestrial CubeSats within the orbit of the Earth around the Sun is hard. As it turns out, this past decade did bring some news from the search. The first interstellar objects were discovered between 2014–2023, and three out of the four of them appeared anomalous, including the two interstellar meteors IM1 and IM2 — which were tougher than all other meteors in the CNEOS fireball catalog of NASA, and `Oumuamua — which had a flat shape and was propelled by a non-gravitational acceleration without showing any trace of cometary evaporation.

Science should be done without prejudice. If we end up concluding based on future data that all interstellar objects are natural rocks, albeit of a type we had never seen before, so be it. We can then decide to move on, taking more cosmic responsibility for shaping our lonely cosmic neighborhood.

But if the forthcoming Galileo Project expedition to retrieve IM1 fragments from the Pacific Ocean, reveals that IM1 was a technological device, then this scientific knowledge will be shared with all humans. If that happens, it would be appropriate for President Biden to add a simple sentence to his next State of the Union address: “My fellow Americans and all humans, as you all know by now — we are not alone!”


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.



Avi Loeb

Avi Loeb is the Baird Professor of Science and Institute director at Harvard University and the bestselling author of “Extraterrestrial” and "Interstellar".