Elon Musk is Wrong About Aliens!

Avi Loeb
6 min readApr 21, 2023


Credit: FOX News via AP

Elon Musk said in a TV interview this week that he has seen “no evidence of aliens” in the Universe, adding that he would tweet about the aliens if he found them.

“A lot of people ask me, you know, where are the aliens? And I think if anyone would know about aliens on Earth it would probably be me. I’m, you know, very familiar with space stuff. And I’ve seen no evidence of aliens,” he argued.

First, as a cosmologist who studies the Universe for his day job, let me clarify that the space explored so far by Elon Musk is smaller than the size of the observable Universe by a factor of a quadrillion, namely one followed by fifteen zeros. Elon commenting about the Universe based on his local experience in the inner solar system is equivalent to an ant making a statement about the planets in the Solar system after exploring an area as big as the head of a pin. It must be a rather presumptuous ant.

Musk’s statement reflects the sentiment of a homebody, looking around his living room and repeating Enrico Fermi’s paradox: “Where is everybody? … It looks like we have no neighbors.” What Enrico and Elon forgot is that to find neighbors, they need to look through the windows and they better use telescopes because of the vastness of space.

Moreover, cosmic times are measured in billions of years, a hundred million times longer than the time we tuned to the sky with modern telescopes. The fraction of Musk’s attention span relative to the age of most stars is equivalent to listening to street signals for a fraction of a second out of a human lifespan. Since most technological civilizations may have existed around stars that formed billions of years before the Sun, they are likely dead by now and the only detectable relics from them are the interstellar spacecraft they launched, in the spirit of SpaceX — Elon’s legacy in space.

Since we know that a significant fraction of all sun-like stars have an Earth-size planet at roughly the same separation, it is likely that Musk-like entrepreneurs created space companies SpaceY or SpaceZ, around other stars, billions of years ago. Sure, Elon is special among humans, but out of the billions of Earth-Sun systems in the Milky Way, there was likely an entrepreneur that ventured to interstellar space. If the parent civilization invested the equivalent of trillions of dollars per year in space exploration instead of military budgets — as we are doing, they could have sent a small probe towards every star in the Milky Way galaxy within a century of their history. We must therefore check whether we have a package in our mailbox rather than wait for a phone call, as the SETI community has been doing over the past seven decades.

Given this perspective, it makes sense to search in space for products of SpaceY or SpaceZ. In fact, we already did.

Over the past decade, astronomers discovered the first four interstellar objects that entered the solar system from outer space. Remarkably, three of them appeared weird, unlike the familiar space rocks within the solar system. They include 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.

Arguing for no evidence without seeking the evidence is a circular argument, akin to a self-fulfilling prophecy. And when anomalies show up, it makes most sense to explore them scientifically rather than repeat Sagan’s standard: “extraordinary claims require extraordinary evidence.” As I often say, “extraordinary evidence requires extraordinary funding,” of the type that Elon can supply.

Changing a scientific paradigm is hard work. Albert Einstein argued in 1935 that quantum mechanics does not have spooky action at a distance, and it took 87 years before the Nobel Prize was awarded in 2022 to the experimentalists who had proved him wrong.

The only way to correct Elon’s misconception about aliens is to engage in scientific observations through state-of-the-art cameras and telescopes. This task defines the mission of the Galileo Project, which represents the first systematic search for objects near Earth of an extraterrestrial technological origin. It would be arrogant of us to ignore the possibility that other civilizations launched probes to interstellar space as SpaceX is doing. It only makes sense to check for SpaceY and SpaceZ.

The Galileo Project follows three branches of research. The first is an effort to find and characterize weird interstellar objects through the data pipeline from the Vera C. Rubin Observatory in Chile and the Webb space telescope — a million miles away, at the second Lagrange point L2. The second branch of the Galileo Project involves an expedition to the Pacific ocean to retrieve relics of the first interstellar meteor and find out from their composition whether its exceptional material strength was natural or artificial in origin. The third effort is to build new observatories that will clarify the nature of Unidentified Aerial Phenomena (UAP), those mentioned by the Director of National Intelligence, Avril Haines, in two reports she delivered to the US Congress. The first Galileo Observatory is already collecting data from state-of-the-art infrared and optical cameras accompanied by a passive radar and audio system. Multiple copies of these sensors will enable reliable distance measurements to UAPs through triangulation.

It took more than a year for the exceptional Galileo team to assemble the first new observatory at Harvard University. We are currently in the process of planning additional observatories at other locations. In order to resolve the UAP puzzle, the Galileo Project needs tens of millions of dollars in funding. The government is not a scientific organization and we cannot expect it to release classified data because it was collected by classified sensors. But the sky is not classified and the Galileo observatories aim to collect new and better data and release this data openly to the public.

If Elon would like to promote scientific knowledge about aliens, all he needs to do is fund the Galileo Project. The Galileo research team will use the scientific method and report back results in the open peer-reviewed literature through a transparent scientific analysis. The Galileo-Musk observatories will bring scientific clarity to a subject that is cluttered with unsubstantiated claims, prejudice, and stigma.

Scientific knowledge about our cosmic neighbors could provide a new meaning to our cosmic existence, which had been pointless until now — as argued by the cosmologist Steven Weinberg. There is nothing more important for singles than to find a partner.


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".