Meanwhile here are 10 weird things about the interstellar object 3I/ATLAS:

1. **Alien Technology Possibility**: Some researchers, notably Avi Loeb and colleagues, speculate that 3I/ATLAS might be an artificial object or alien spacecraft. This is based on its unusual trajectory, size estimates, and lack of expected chemical signatures typical of comets or asteroids.

2. **Improbably Large Size**: Initial observations suggested 3I/ATLAS is much larger than expected for interstellar objects, possibly more than 3 miles in diameter, which challenges existing theories about the population and size distribution of such objects in the galaxy.

3. **Unusual Trajectory Close to Planets**: Its path takes it unusually close to key planets like Venus, Mars, and Jupiter, which some speculate might indicate it was purposefully directed toward these bodies, suggesting potential surveillance or reconnaissance.

4. **Non-Gravitational Acceleration**: The object exhibits acceleration that cannot be fully explained by gravity alone, which some interpret as evidence of active propulsion or outgassing that is mysterious due to incomplete chemical detections.

5. **Chemical Signature Mysteries**: While comet-like outgassing has been detected (water, CO2, cyanide), early observations showed strangely weak or absent carbon-based molecules usually abundant in comets, fueling alternative theories.

6. **Historical Suppression of Anomalies**: Avi Loeb has claimed there is a gatekeeping effort by mainstream science to downplay or exclude anomalous findings about 3I/ATLAS, drawing comparisons to Galileo’s persecution, framing it as a suppressed truth story.

7. **Size and Brightness Incongruity**: Discrepancies between brightness and size have led to speculation that much of the light reflects from its coma (gas/dust envelope) rather than a solid nucleus, leading to theories that the nucleus may be very small or hollow (if artificial).

8. **Possible Ancient Origin**: The object is considered very old, possibly the oldest comet observed, which prompts bizarre ideas such as it being a long-lost probe or artifact from an extinct alien civilization.

9. **Trajectory Defies Randomness**: Statistical arguments show it’s extremely unlikely to randomly encounter such a large interstellar object with its specific path through the solar system, raising suspicions of a targeted visit.

10. **Interstellar \"Message in a Bottle\"**: Some speculative interpretations paint 3I/ATLAS as a cosmic message or probe, sent intentionally over vast interstellar distances possibly to seed or monitor life in other star systems, including ours.

These points illustrate a mix of factual scientific observations, speculative interpretations, and conspiracy-like suspicions surrounding 3I/ATLAS from its discovery to the present debate.

Sources
[1] Avi and 3I/ATLAS | AstroWright https://sites.psu.edu/astrowright/2025/07/18/avi-and-3i-atlas/
[2] 3I/ATLAS https://en.wikipedia.org/wiki/3I/ATLAS
[3] Comet 3I/ATLAS Larger Than Expected, Could Be Alien ... https://www.ndtv.com/science/comet-3i-atlas-larger-than-expected-could-be-alien-probe-astrophysicist-9370941
[4] 7 Big Mysteries about Interstellar Object 3I/ATLAS https://www.scientificamerican.com/article/new-interstellar-object-3i-atlass-biggest-mysteries-explained/
[5] Everything We Know About 3I/ATLAS, the New 'Oumuamua https://www.youtube.com/watch?v=XEggZo3SXNM
[6] Here's what astronomers know so far about the 3rd ... https://www.cbc.ca/news/science/3i-atlas-comet-what-we-know-1.7632397
[7] 3I/ATLAS: The third interstellar object ever found https://www.planetary.org/planetary-radio/2025-3i-atlas
[8] \"This Thing Is Bigger Than We Thought\": Harvard Scientist ... https://www.rudebaguette.com/en/2025/09/this-thing-is-bigger-than-we-thought-harvard-scientist-says-33-billion-ton-space-rock-might-be-alien-technology/
[9] Interstellar invader comet 3I/ATLAS could be investigated ... https://www.space.com/astronomy/interstellar-invader-comet-3i-atlas-could-be-investigated-by-these-spacecraft-as-it-races-past-the-sun-this-could-be-literally-a-once-in-a-lifetime-opportunity
[10] Avi Loeb: 3I/ATLAS is far more massive than expected https://www.youtube.com/watch?v=z-5xEa6UIZs
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