As the interstellar object 3I/ATLAS speeds through the solar system, Harvard astronomer Avi Loeb is keeping the possibility of it not being an ordinary comet alive. While most scientists classify 3I/ATLAS as a carbon dioxide-rich comet, Loeb points to its unusual chemical makeup, massive size, and close planetary encounters as reasons to consider it an “alien” of a more exotic origin.
“I'm very much looking forward to getting more data in the coming weeks,” Loeb told NewsNation. “You know, that's the way science should be done. It's like a detective story, and any of my colleagues who claim to know it's a comet of a type that is familiar to us is not really curious or imaginative about nature.”
3I/ATLAS is expected to make its closest approach to Earth on December 19, passing within 270 million km, and will later fly by Jupiter in March, offering additional observation opportunities.
NASA's HiRISE camera on the Mars Reconnaissance Orbiter captured images of the object in October, but their release was delayed by the government shutdown.
“Let's just keep our fingers crossed,” Loeb said regarding the upcoming image release. He also criticised bureaucratic delays, writing in a blog post that “sharing of scientific data should have been prioritised over bureaucratic rules, because the data is time-sensitive as we plan additional observations of 3I/ATLAS.”
New photos from the Nordic Optical Telescope in Spain show that 3I/ATLAS survived its closest approach to the Sun intact. Loeb argued that the object's massive jets, extending up to a million km toward the Sun, are difficult to explain with natural cometary behaviour.
The comet is currently speeding away from the Sun, and amateur astronomers can now witness it in real time.
The comet, discovered on July 1, 2025, came out from behind the glare of the Sun after reaching its closest approach, or perihelion, on October 30. It is currently visible from the eastern horizon before dawn, travelling through the constellation Virgo. With an estimated magnitude of +10.9, it is too dim to see with the naked eye but can be observed with a small backyard telescope as a fuzzy, glowing blob against the stars.
Astronomy enthusiasts can tune in to a livestream hosted by the Virtual Telescope Project at 9:45 am IST on November 19 featuring live robotic telescope views from Manciano, Italy. The event was originally scheduled for November 16 but was delayed due to poor weather.
“The surface area required to account for the mass flow in the large-scale jets… is untenable,” Loeb told The NY Post. He suggested these jets could be “technological thrusters which point their exhaust towards the sun,” allowing the object to accelerate out of the solar system.
Other scientists disagree. Michigan State University astronomer Darryl Seligman said, “The fact that 3I/ATLAS did not disintegrate is exactly in line with what I expected to happen.” Observations from the MeerKAT radio telescope in South Africa detected hydroxyl radicals, signs that water is being broken down by sunlight, supporting its cometary identity.
“The truth about the nature of 3I/ATLAS will be revealed by publicly shared data and not by any storyline of gatekeepers,” Loeb wrote in a blog post.
