There has been much hype and discussion surrounding 3I/ATLAS since it was first spotted in our Solar System back in 1 July 2025.
Unlike the vast majority of comets we observe from Earth, which originate from the outer edges of our Solar System, 3I/ATLAS is an ‘interstellar visitor’.
That means it was born out in deep space, it’s temporarily passing through our Solar System, and will eventually exit our Solar System.
It’s one of only three such bodies known, the other two being 1I/ʻOumuamua, discovered in 2017, and 2I/Borisov, discovered in 2019.
And among some voices at least, there’s discussion as to whether interstellar visitors like this could in fact be extra-terrestrial technology.
It sounds unbelievable, but the idea seems to have more traction among science circles than you might think.
Harvard scientist Avi Loeb is one prominent voice within discussions about objects like ʻOumuamua and 3I/ATLAS, and someone who is open to the possibility of investigating whether they are exhibiting properties similar to how alien spacecraft might behave.
Now, in a blog posted on 18 August 2025, Avi Loeb says there’s evidence that 3I/ATLAS could be producing its own light.
Why 3I/ATLAS could be producing its own light
In the blog post, Loeb looks to the recent Hubble Space Telescope image of 3I/ATLAS.
“The image shows a glow of light, likely from a coma, ahead of the motion of 3I/ATLAS towards the Sun. There is no evidence for a bright cometary tail in the opposite direction,” he writes.
“This glow was interpreted as evaporation of dust from the Sun-facing side of 3I/ATLAS.”
After analysis of the light emitted by 3I/ATLAS, as described in a science paper published on 20 August 2025, Loeb then writes:
“The simplest interpretation is that the nucleus of 3I/ATLAS produces most of the light.”
And:
“3I/ATLAS could be a spacecraft powered by nuclear energy, and the dust emitted from its frontal surface might be from dirt that accumulated on its surface during its interstellar travel.
“This cannot be ruled out, but requires better evidence to be viable.”
He continues:
“This leaves us with the interpretation of the brightness profile around 3I/ATLAS as originating from a central light source. Its potential technological origin is supported by its fine-tuned trajectory.”
What’s more, Loeb argues the data could be interpreted as showing that “3I/ATLAS could in fact comparable size to the previous interstellar objects 1I/`Oumuamua or 2I/Borisov.”
Of course, these are just snippets from a larger blog post drilling down into the possible sources of the object’s light.
The full post is a fascinating read, and breaks down the science behind Loeb’s interpretation of the data on 3I/ATLAS collected by the Hubble Space Telescope.
Naturally, Loeb’s comments surrounding these interstellar objects draw much discussion and debate online, from those both agreeing and disagreeing with his analyses.
But whatever your own thoughts, Loeb’s comments are an interesting, thought-provoking addition to the discourse around these strange objects passing through our stellar neighbourhood from the depths of the cosmos.
What are your thoughts on 3I/ATLAS? Let us know by emailing contactus@skyatnightmagazine.com