comet

Avi Loeb is back at it. While NASA deploys an unprecedented fleet of cameras and telescopes to observe the third interstellar visitor in history, the Harvard physicist points out an orbital coincidence with Jupiter so precise that, in the absence of explanation, it defies chance. A little context. The solar system has a new guest object and, as it happened with its only two known predecessors‘Oumuamua and 2I/Borisov, has not arrived without controversy. The interstellar comet 3I/ATLAS, discovered in July 2025, is on track to make its closest approach to Earth. For NASA, it is a golden opportunity to study the chemistry of another solar system. For the controversial astrophysicist Avi Loeb, director of the Galileo Project, the orbital data has just revealed an “extraordinary anomaly” that, for the umpteenth timehas been associated with a possible artificial origin. A chance of 1 in 26,000. According to the latest trajectory data from NASA’s JPL, 3I/ATLAS will pass the closest point of its trajectory to Jupiter on March 16, 2026. But what’s surprising is not the approach itself, Loeb says, but the exact distance at which it will occur. If a mother ship wanted to “seed devices” on Jupiter or take advantage of its Lagrangian points to park with a minimum expenditure of fuel, it would have to arrive right at the edge of the so-called Hill Radius, which delimits the sphere of gravitational influence of the gas giant. By the date of the encounter, Jupiter’s Hill Radius will be 53.502 million kilometers. The fact that has raised Loeb’s eyebrows? The minimum approach distance of 3I/ATLAS is 53.445 million kilometers. According to the cosmologistthe probability of an interstellar rock randomly passing with this precision by the edge of Jupiter’s Hill Radius is about 1 in 26,000. Engines or degassing? NASA had already ruled out that the “non-gravitational acceleration” observed in 3I/ATLAS came from artificial engines. 3I/ATLAS It is an active comet. As such, as it approaches the Sun, the heat sublimates the ice in its body, creating jets of gas that act as natural propellants, pushing the rock and altering its orbit. However, Loeb argues that this observed acceleration during perihelion (the closest point to the Sun) was of the exact magnitude needed to correct course toward that precise intersection with Jupiter’s Hill sphere. If it were a technological spacecraft, Loeb argues, those observed “jets” might not be ice sublimating, but thrusters performing a gravity-assist maneuver. We will clear up doubts. The outcome of this story will come in the coming months. On December 19 we will have the comet’s closest approach to Earth, an ideal time for detailed spectroscopic observations. A spectroscopic measurement of the speed and composition of the jets will reveal whether they come from the sublimation of ice packs or from technological propellants. If in March 2026, after passing by Jupiter, we detect new objects orbiting the gas giant that we did not send, the history of humanity could change. If not, we will have had the unique opportunity to closely study a fragment of an alien world, which, as NASA tries to argue, is already extraordinary in its own right. Image | POT In Xataka | NASA has been accused of “kidnapping” the 3I/ATLAS photos for a month and a half: it has had no choice but to publish them