Afterthoughts on the Second UAP Senate Hearing

Avi Loeb
5 min readApr 19


On April 19, 2023, the director of the All-domain Anomaly Resolution Office (AARO), Dr. Sean M. Kirkpatrick, was the sole witness in a public hearing at the Senate Subcommittee on Emerging Threats and Capabilities, chaired by Senator Kirsten Gillibrand. This was the second in two public hearings on Unidentified Aerial Phenomena (UAPs), held merely a year apart over the past half century. In a follow-up NewsNation interview, I was asked why the rush all of a sudden?

UAPs cannot be ignored by the US government because they may represent advanced technological capabilities of adversaries which pose national security threats. This was evident from Dr. Kirpatrick’s presentation, which revolved around these concerns. He noted that 650 reports are being studied by two teams within AARO: one led by intelligence experts and the other by scientists and engineers. For each UAP report, the inferences from the two teams are compared and vetted, with the goal of transforming UAP to SEP (“Someone Else’s Problem”), namely an item to be handled by other government agencies. The reporting procedures and filters for cataloging data will improve over time, as more UAPs are reported and studied. Half of the existing reports involve nearly spherical objects, which could potentially be balloons.

AARO studies anecdotal data that was obtained during the routine operation of military and intelligence sensors, but not through a systematic scientific study of the sky. Moreover, the best quality data will remain classified because the government sensors used to collect them are classified.

But UAPs should not be ignored also for scientific reasons, in case some of them have an extraterrestrial origin. Dr. Kirkpatrick showed two video snippets of objects that were not particularly likely to be candidates for extraterrestrial devices. He said: “I should also state clearly for the record that in our research, AARO has found no credible evidence thus far of extraterrestrial activity, off-world technology or objects that defy the known laws of physics.”

To find out if one in a thousand UAPs or interstellar objects represents an extraterrestrial technology, we must observe it with state-of-the-art cameras and telescopes that are fully calibrated and understood. Only exquisite scientific data will allow us to test whether humanity is the most technologically advanced species in the Milky Way galaxy.

For example, the Webb space telescope could detect the heat emitted by the next weird interstellar object, like `Oumuamua, and infer its surface area and albedo — given that its surface temperature is dictated by its distance from the Sun. Simultaneous observations from Earth and the Webb telescope will accurately constrain the 3D trajectory of the object and any meaningful level of non-gravitational propulsion. New interstellar objects will likely be discovered in the coming years by the 3.2-billion-pixel camera of the forthcoming Vera C. Rubin Observatory in Chile.

The best path forward on the scientific front is not to focus on past anecdotal data by classified government sensors — as that pursued by AARO and the Senate subcommittee, but instead to collect new data. This is precisely the mission of the Galileo Project observatories, the first of which is currently recording continuous data on the entire sky from Harvard University. The Galileo research team plans to build multiple copies of this observatory and place them in different geographical locations within the coming year. The vast output of infrared, optical, radio and audio data, will be analyzed systematically by artificial intelligence classification algorithms in search for anything other than natural or human-made objects that AARO aims to transition to the SEP category. Any SEP is boring for the scientific mission of the Galileo Project. In other words, this scientific mission complements the analysis of anecdotal data from past UAP reports, discussed during the Senate hearing.

Within the coming years, the Galileo Project’s data will contain more information than all past UAP reports combined. Rather than attend to compromised or crowdsourced data from cell phones, it makes most sense to expand our scientific knowledge by using well-calibrated instruments under the control of experienced scientists.

Dr. Kirkpatrick noted that NASA is conducting a parallel study that analyzes data from its climate-monitoring satellites around Earth. However, these satellites cannot resolve UAPs that are a few meters in size. The Galileo Project is currently analyzing higher-resolution data obtained through a partnership with Planet Labs, that allows the imaging of UAPs of interest.

Dr. Kirpatrick reiterated the need for evidence-based, rigorous scientific analysis. Along these lines, I co-authored a joint paper with him last month that discusses the path forward to using known physics in constraining the properties of UAPs. In the Introduction section of our paper, we discussed hypothetical scenarios by which UAPs might represent small probes from an extraterrestrial technological origin. Humanity launched five probes to interstellar space in 50 years and could send tens of billions of them in the next 50 years by allocating all military budget to space exploration. That we do not have any conclusive data to support the possibility that another technological civilization did that already, is the rationale behind the Galileo Project. It would be arrogant for us to ignore this possibility based on prejudice.

Since Fritz Zwicky’s discovery ninety years ago, astronomers are aware of the fact that most of the matter in the Universe is composed of a different substance than the ordinary matter we see in the Solar system. To find the nature of dark matter, particle physicists are smashing protons at yet higher energies in the Large Hadron Collider at CERN. Similarly, astronomers learned over the past decade that three out of the first four interstellar objects (ISOs) from outside the Solar system, have anomalous characteristics relative to solar system rocks. To figure out the nature of ISOs and UAPs, the Galileo Project is collecting new data. Beyond any clutter from national security threats, the latter quest for ISOs may have much broader implications to the future of humanity than the former search for dark matter particles.

The scientific process takes much more time and effort than the speculations of believers, skeptics, bloggers or science-fiction writers. But this hard work is worth the wait. Our current assets in space would never reach their destinations if we relied merely on popular views from four centuries ago, and kept avoiding the scientific method pioneered by Galileo Galilei.


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".