Goodbye, 3I/ATLAS: Object Won't Be Visible Again Until Early December

A mysterious object from interstellar space, 3I/ATLAS, is currently making its closest approach to our Sun. This critical event, its perihelion, is happening today, 29 October 2025. But as it skims the inner Solar System, hidden from Earth's view, one controversial scientist is watching for more than just a cometary glow.

Harvard astrophysicist Avi Loeb, who has long proposed that 3I/ATLAS is no mere comet, has once again sparked a fierce debate. He suggests this fly-by is the moment of truth, and that the object could even release 'mini-probes' just in time for Christmas.

The Perihelion 'Acid Test' for 3I/ATLAS

Today, 3I/ATLAS reaches its perihelion at around 11:47 Universal Time (UT). It will pass at a distance of 1.36 Astronomical Units (AU), or roughly 203 million kilometres, from the Sun. While this celestial milestone is significant, the object is almost directly opposite to Earth and will be unobservable for weeks. According to NASA, "It will reappear on the other side of the Sun by early December 2025".

This timing is crucial. In his latest Medium essay, titled 'The Acid Test of 3I/ATLAS at Perihelion,' Loeb speculates that this is the precise moment the object could exhibit technological behaviour. The intense solar heating, he argues, will force 3I/ATLAS to show its true nature.

A Natural Comet or a Manufactured 3I/ATLAS?

Loeb's 'acid test' presents two distinct outcomes. The first is the conventional one: 3I/ATLAS is just a comet. 'If it is a natural comet glued together by weak forces, its heating by 770 watts per square meter may break it up into fragments,' he explained. This would be the expected behaviour for a natural object.

But Loeb, pointing to what he claims are anomalies like 'its high abundance of nickel relative to iron,' suggests a second, more startling, outcome. 'However, if 3I/ATLAS was technologically manufactured... it might maneuver or release mini-probes.'

He has previously claimed on his Medium blog that the mysterious interstellar object might be an 'alien mothership.' In that scenario, he wrote: 'If 3I/ATLAS is a massive mothership, it will likely continue along its original gravitational path and ultimately exit the Solar system.'

'Christmas Gifts': Will 3I/ATLAS Send Probes to Earth?

Loeb's most provocative theory centres on these potential 'mini-probes.' He wrote: 'Will 3I/ATLAS send mini-probes towards Earth as Christmas gifts to humanity?'

This is not just idle speculation for him; his Galileo Project research team is actively preparing. Loeb states they are monitoring for 'any unusual activity by anomalous objects in the Earth's atmosphere based on data collected by the three Galileo Observatories in the coming months.' This implies he believes these 'gifts' could be inbound, warranting closer scrutiny as 3I/ATLAS gets closer to Earth.

The 3I/ATLAS Timeline: When to Watch the Skies

While the perihelion is today, Loeb suggests the real date to watch is 19 December 2025. On that day, 3I/ATLAS will reach its closest approach to Earth, at a distance of 267 million kilometres.

In a recent interview with FOX News, when asked when we might know about these predicted gifts, he was clear about the date. 'In the coming months, it will come closest to Earth on December 19th, just six days before Christmas.' But he concluded his thought with a more ominous tone: 'And my hope is it will not send us any gifts.'

As 3I/ATLAS completes its 'acid test' behind the Sun, the world must wait for it to re-emerge in December. The key date to watch is 19 December, when the object makes its closest approach to Earth. Will it be a silent, fragmenting comet, or will Avi Loeb's Galileo Project detect the 'Christmas gifts' he has ominously warned about? Keep watching the skies as this interstellar mystery continues to unfold.