Zoom image will be displayedImage of the interstellar object 3I/ATLAS, taken by the Hubble Space Telescope on 21 July 2025. (Image credit: David Jewitt/NASA/ESA/STScI)
So far, the new interstellar object 3I/ATLAS appears as a compact ball of light, somewhat larger than the image of background stars that appear point-like because of their much larger distance. We must keep our eyes on the ball rather than on the number of “likes” we get on social media for opinions about the nature of this interstellar object. As 3I/ATLAS gets closer to the Sun, it will be warmed by absorbing sunlight. If it is indeed a comet similar to 2I/Borisov, then its outgassing will result in an extended coma of dust and gas.
Claiming that 3I/ATLAS is definitely a comet with water ice is premature. A recent paper used the infrared spectrum of 3I/ATLAS to suggest spectral features associated with water ice. However, a careful inspection of the observed noisy spectrum reveals an upturn at the wavelength for which the water model predicts a downturn, and vice versa. A proper statistical analysis is needed to demonstrate that the water model does better than the spectrum of L-type asteroids. These asteroids have a hard surface and no coma and the upper envelope of their possible spectra fits the observed data perfectly. The paper does not provide such an analysis, yet its title announces “Water Ice in the Coma”.
Many commentators who criticize alternative interpretations of 3I/ATLAS did not write a single scientific paper over the past decade. They claim to protect science, but who are they protecting it from? Scientists like myself are in the trenches of doing science. Over the past three weeks, I wrote four scientific papers on 3I/ATLAS (accessible here, here, here, and here). By all measures, those who know the answers in advance of conclusive data are anti-science. Their loud voices on social media disrupt agnostic scientific discourse which must be based on rigorous analysis of data and not be amplified by the megaphone of social media.
Science is work in progress and should be portrayed to the public that way. The fun of searching for scientific knowledge is that most of the time we have multiple possible interpretations, and they motivate us to do the hard work of collecting more data and analyzing it to identify the correct interpretation.
Uncertainty makes scientific inquiry exciting. The risk of being wrong inspires financial investments, as Polymarket recently opened bets on whether 3I/ATLAS is natural or artificial. The best practice in blind dates, terrestrial or interstellar, is to observe our date before having an opinion about it.
Genuine curiosity inspires the public. This was evident from the following messages that I received over the past few days:
Message 1: “Dear Mr. Musk and Dr. Loeb,
I am an independent observer with no public platform, just a dude, driven by a clear view of the stakes surrounding the interstellar object 3I/ATLAS, discovered July 1, 2025. Your work — Musk’s vision for humanity’s cosmic future and Loeb’s bold hypotheses on extraterrestrial technology — inspires my call for immediate action: launch a rapid probe to intercept 3I/ATLAS before its November 2025 solar approach. The window is closing, and inaction risks repeating the ‘Oumuamua regret of 2017. You both must admit missing that opportunity still stings the scientific community.
Dr. Loeb’s work suggests that 3I/ATLAS could be artificial, potentially executing a covert maneuver by November. While likely a comet, its lack of a tail and unusual trajectory demands closer scrutiny. A probe could confirm its nature — natural or alien — before it’s too late. Mr. Musk, your SpaceX launches (2–3 weekly) and mission to secure humanity’s future make you uniquely positioned to act. A CubeSat with cameras and signal detectors, launched by September or October, could be a historic win.
This is a no-lose mission:
• If Natural: Close-up data on an interstellar object yields unprecedented science, surpassing telescope limits and avoiding ‘Oumuamua’s missed opportunity.
• If Artificial: Early detection of a trajectory-change or of signals gives months to prepare for first contact or, worst case, a threat — critical with November’s deadline looming.
Why act now? Telescopes, while valuable, can’t match a probe’s detail, and waiting for pre-November data risks leaving no time for action. A trajectory shift, as Dr. Loeb notes, could confirm intelligence, but by November, it would be too late to respond. SpaceX’s rapid launch capability could deploy a probe in months, privately funded or via NASA, ensuring no regret.
I urge you: Dr. Loeb, publicly advocate for a probe to bolster your hypothesis with hard data. Mr. Musk, lead or gain a following to fund a mission, cementing your legacy as humanity’s cosmic pioneer. Collaborate to make this happen — NASA, private groups, or both. The cost is minor compared to the stakes: scientific triumph or existential preparedness.
As an outsider, I see what the crowd misses. I don’t have X (forgive me Mr. Musk) and don’t follow the crowd’s “shiny object” of the week. Please act before November 2025 proves me right about the regret of inaction.
Sincerely, […]”
Message 2: “Dear Professor Loeb,
We are co-founders of Nøha (Not Only Human Architecture), a design studio based between Zürich and Beijing. We are architects working across ecology, culture and economy.
We were selected for this year’s Zürich Design Biennale themed Side by Side. Our project is an art installation that imagines how future archaeologists — human or not — might interpret the techno-fossils and digital traces of our present. The installation reflects on what survives from our hyperconnected present, how it is interpreted, and what might be lost in translation when memory is no longer human.
We came across the Galileo Project when doing research around our upcoming installation and found your work fascinating and very resonant with the topics that we touch upon.
Warm regards,”
Message 3: “Dear Professor Loeb,
I am writing to you from Iran.
I have been deeply inspired by your bold and thoughtful perspectives on interstellar phenomena and the search for extraterrestrial intelligence. Your scientific courage and openness to exploring unconventional ideas — especially regarding interstellar objects like 1I/ʻOumuamua and 3I/ATLAS have truly resonated with me.
I want you to know that there are people like me in other parts of the world who admire your work and share your curiosity. I truly believe in your words and vision. It would be an honor for me to meet you in person one day, if the opportunity ever arises.
Thank you for your valuable contributions to science and for encouraging open-minded exploration. Wishing you continued success and inspiration in your research.
Warm regards, […]”
Message 4: “Dear Avi,
I write because my father passed away two weeks ago. Your contribution to the popularization of science was one of the things that brought us together during his final years. He always wished to have met you in person. Thank you! […]”
Message 5: “Dear Dr. Loeb,
I want to personally share how honored I am […] I’ve been a longtime admirer of your work, especially your leadership on The Galileo Project and your research into interstellar artifacts and the UAP phenomenon. Your contributions have had a profound impact on both the scientific community and the public’s understanding of these fascinating topics.
With deep gratitude, […]”
The sense of gratitude I felt after receiving these messages is encapsulated in the Talmudic phrase: “The righteous have their work done by others.”
ABOUT THE AUTHOR
Zoom image will be displayed(Image Credit: Chris Michel, National Academy of Sciences, 2023)
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. The paperback edition of his new book, titled “Interstellar”, was published in August 2024.