Running Along IM1’s Likely Path

Avi Loeb
5 min readJun 26, 2023

Diary of an Interstellar Voyage, Report 30

(June 26, 2023)

A documentary crew filming Avi Loeb’s morning jog at sunrise on the deck of Silver Star with one of their cameras on a drone. The ocean waves crashed against the back deck as the magnetic sled was carried behind the ship (through a thin cable, visible in the back) in search for the remains of the first recognized interstellar meteor, IM1 (June 26, 2023).

The documentary director, Jason Kohn, asked me after my morning jog at sunrise on the deck of Silver Star: “Are you running away or towards something?” I answered: “Both. I am running away from some of my colleagues and towards a higher intelligence in interstellar space.”

Over the past couple of weeks, we have been searching for the remains of the first recognized interstellar meteor, IM1, which had material strength above all known space rocks and was moving faster than 95% of all stars in the vicinity of the Sun. The possibility that it might have been technological in origin brought me to the Pacific Ocean along with a team of almost two dozen researchers and support staff, arguably the best in the world. And most importantly, it looks like we have recovered traces of these remains. Now we need to bring them back to the Harvard College Observatory and analyze their element composition and radioactive isotope abundances.

The interstellar origin of IM1 was already established by its high velocity relative to the Sun. This was confirmed with a statistical confidence of 99.999% in a formal letter from the US Space Command under the Department of Defense (DoD) to NASA.

The immediate task before us is to confirm the interstellar origin of the spherules we collected from the ocean floor by showing that it lacks short-lived isotopes because of its long journey in interstellar space. In addition, we need to show that its element abundance pattern is different from solar system rocks. We intend to test these telltale signatures with state-of-the-art instruments upon our return to the US towards the end of this week.

Avi Loeb is holding the two biggest magnetic fragments recovered so far, both in Run 21 which proceeded along the northwest direction towards the middle of the western side of the DoD error box. This region is indeed expected to contain larger fragments of IM1, but the association with the earlier discovered population of spherules has to be confirmed through a composition analysis.

A few minutes ago, we retrieved the magnetic material from Run 21 of the magnetic sled. This run continued farther along the likely path of IM1 where larger fragments are supposed to be scattered. As we approached the sled, we noticed two big objects attached to its front section magnets with non-spherical shapes attached to it. If these are related to IM1, they would account for most of the mass residue we recovered so far from IM1, totaling thousands of times more total mass than the spherules of size 300-microns. If related to IM1, they would allow us to get exquisite precision on the make-up of the meteor.

Images of the largest magnetic fragments retrieved so far. They were found near the front of the magnetic sled in Run 21.
Expedition team member Jeff Pugh, is vacuuming the sled magnets of Run 21, while other team members are watching him. From left: Toby Adamson, Charles Hoskinson and Peter Smith.

Together with Art Wright we went over the existing data on spherule abundance and sizes in all runs. We concluded that the meteor trail started in a narrow band of 50 micron particles near the intersection of the DoD error box with the likely path of IM1 based on seismometer data from Manus Island. The trail broadened to a few kilometer wide spray of 300 micron particles around the middle of the likely IM1’s path and ended with larger particles across a 5-kilometer-width region to the northeast region above the original seismometer arc for IM1’s fireball.

After demonstrating the interstellar origin in these three independent ways, there should be no doubt that the material we collected with our magnetic sleds is from IM1.

This morning I assigned my daughter, Lotem, who was admitted to Harvard College and is taking an internship at Harvard’s Earth & Planetary Sciences department this summer, the task of searching for more spherules and finding them as shiny metallic marbles that may have been missed on the scale down to 50 microns.

The biggest question is whether IM1 was natural or technological in origin. This question may be addressed by the materials we already possess. But its definitive proof will come from finding a remnant object at the bottom of the ocean with a 30-kilohertz sonar. We can circle that potential location and survey it in our next expedition.

One way or another, we will learn something new about the stars by exploring the ocean. Ad Astra!


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".