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The Voyager 1 spacecraft will exit the outer edge of the Oort cloud at 100,000 times the Earth-Sun separation in about 30,000 years. Roughly 10,000 years later, Voyager 1 will pass within 1.6 light years from the red dwarf star Gliese 445, currently located at a distance of 17.6 light years from Earth. In the more distant future, billions of years from now, Voyager 1 could collide with an Earth-like exoplanet along its path. In that case, it would appear as an interstellar meteor in the exoplanet’s sky. Meteor experts on that exoplanet might dismiss the event as a common impact by a natural rock. But perhaps among them, there will be one curious astrophysicist who would be intrigued by the anomalous properties of this interstellar meteor and check whether it might be technological in origin. The astrophysicist might lead an expedition to retrieve materials from the impact site, and ignore the ridicule from academic peers and the gatekeeping of scientific journals. That astrophysicist might discover that they are not alone. And we are not alone. That astrophysicist would be my kindred spirit.
I love kindred spirits. A few days ago, Stephon Alexander, currently a distinguished physics professor at Brown University, told me that he vividly remembers attending a conference in Iceland as a fledgling scientist two decades ago, where he felt alone until a like-minded Harvard professor made him feel welcome. “That was you!”, he said.
Sensors on U.S. government satellites continuously monitor Earth for signals of heat from launches of ballistic missiles. Occasionally they detect meteor fireballs. This data is eventually documented in a database here maintained by NASA/JPL’s Center for Near Earth Object Studies (CNEOS). A new paper, available here, that I just co-authored with the brilliant Professor Volkan Duran, addresses the important question of whether there are interstellar meteors in the CNEOS database which exceed the escape speed from the Solar system.
The CNEOS catalogue provides a near-global record of bright atmospheric entries but does not report velocity uncertainties. Our new paper calibrates the kinematic accuracy of CNEOS reports using 19 events with independent reference trajectories from ground-based data. We use optical, satellite, radar, and infrasound catalogues. For 9 high-quality comparisons, the CNEOS-minus-reference speed residual has a mean of -1.00 (+/-0.86) kilometers per second. Seven of 354 complete CNEOS reports are potentially interstellar. The Polar-IM event from April 1, 2026, which I discovered with my postdoc Richard Cloete here, is the strongest post-2018 CNEOS anomaly, but independent data here allow for marginally bound orbit.
The discovery of 1I/ʻOumuamua, 2I/Borisov, and 3I/ATLAS demonstrates that macroscopic interstellar bodies traverse the inner Solar System. At meteoroid sizes, atmospheric entry provides a large effective collecting area, but hyperbolic classifications are sensitive to measurement error. The CNEOS fireball catalogue is the only near-global public record of meter-scale atmospheric impactors and reports three-component Earth-fixed velocity vectors for a subset of events, but it does not provide velocity uncertainties. A fireball is classified as interstellar when its reconstructed speed relative to the Sun exceeds the local solar escape speed, but the margin above that boundary is typically a few kilometers per second which is of the same order as the plausible measurement error.
Our analysis, available here, calibrates the CNEOS uncertainties and evaluates nominally hyperbolic events under an explicit hierarchy of evidence. Taken together, the public record can rank high-priority follow-up events and identify the assumptions controlling their classification, but it does not establish an interstellar meteor from any single CNEOS case. For Polar-IM, the next decisive step is a joint, uncertainty-bearing three-dimensional reconstruction of the independent stereo observations.
The CNEOS database sets an important example in the search for alien technology. Even when data is obtained by classified sensors, it is possible to release scientifically-valuable information such as meteor velocity, location and energy output, without compromising classified information about the sensors used to collect it. As chair of the UAP Science Advisory Council, I hope to motivate the U.S. government to similarly release information on Unidentified Anomalous Phenomena (UAP) without compromising classified information about the related sensors and context. Whether any of the meteor or UAP data relates to a Voyager-like probe remains to be seen.
Today, a small asteroid, designated CERNQ52, was detected by the Mount Lemmon Observatory (part of the Catalina Sky Survey) just hours before impact. It entered Earth’s atmosphere over the Indian Ocean, northwest of Australia, in the time window of 16:00–16:30 UTC, producing a bright but completely harmless fireball. The meteoroid diameter was approximately 0.8–1 meter. This is the 13th time an asteroid has been successfully detected and its atmospheric entry predicted before impact.
Authorized publication by Dr.Avi Loeb
