3i/atlas have you heard of it?

[neanderthal]

So 3i/atlas have you heard of it?

Or is it my YouTube going mental?

if you’ve heard of it what do you think?

[Wonderer]

I keep seeing non-reputable pages on Facebook posting about it.

Idk.

I’m trying not to catastrophize things..

[Sebastien-Casse]

I really hope it’s an alien craft. I saw interviews of Avi Loeb, Harvard astrophysicist, suggesting it could be an alien craft.

[77nick77]

ChatGPT said:

Yes — “3I/ATLAS” refers to a newly discovered interstellar comet (i.e. an object not bound to our Solar System) that is currently passing through. NASA Science+4NASA Science+4Wikipedia+4

Here’s a summary of what’s known so far (and what’s still uncertain):

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What we do know

• Designation & discovery
  It’s officially called 3I/ATLAS (also known as C/2025 N1 (ATLAS)). NASA Science+3Wikipedia+3European Space Agency+3
  It was first observed on July 1, 2025 by an ATLAS telescope in Chile. European Space Agency+4NASA Science+4NASA Science+4

• Interstellar origin
  Its trajectory is hyperbolic (i.e. not bound to the Sun), meaning it came from outside our Solar System. NASA Science+3NASA Science+3European Space Agency+3

• Observations & instruments
  It has been observed by many telescopes and space instruments, including the Hubble Space Telescope, the James Webb Space Telescope, and ground‐based telescopes in Hawaii, Chile, Australia, etc. NASA Science+8European Space Agency+8NASA Science+8
  Infrared spectral studies (e.g. with JWST) have begun revealing its composition (water ice, carbon dioxide, etc.). ScienceAlert+4European Space Agency+4Sky at Night Magazine+4

• Physical characteristics & anomalies

  • It is estimated to be extremely massive, perhaps more so than initially expected. Some estimates suggest tens of billions of tons of mass. NASA Science+7ABC News+7Medium+7

  • Some papers suggest a nucleus perhaps 5.6 km diameter, or even speculation (by Avi Loeb, among others) that it could be as large as ~15 km, though that is quite uncertain and model‐dependent. NASA Science+6Medium+6Medium+6

  • It exhibits anomalous features such as an anti‐tail (a glow or extension facing toward the Sun, rather than away) which is unusual for comets. ScienceAlert+3Medium+3NASA Science+3

  • Its tail is forming/growing as it nears the Sun. Planetary Society+3ScienceAlert+3Universe Today+3

  • The lack of detectable non‐gravitational acceleration (i.e. extra “push” due to outgassing) is interpreted in some work as implying it’s more massive (so gas outflows have relatively smaller effect) than might be expected for a typical comet. The Debrief+3Medium+3Medium+3

• Orbit & future path

  • It will make its closest approach to the Sun (perihelion) around October 30, 2025 (at a distance inside Mars’ orbit) TheSkyLive+4Gemini Education+4NASA Science+4

  • The closest approach to Earth will be on December 19, 2025, at about 1.797 AU (≈ 269 million km). Gemini Education+3TheSkyLive+3NASA Science+3

  • After passing through, it will continue outward, leaving the Solar System. NASA Science+3NASA Science+3European Space Agency+3

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What’s uncertain / speculative

• Exact size and mass
  Because of uncertainties in surface activity, dust/gas shedding, and observational limits, the true nucleus size and mass remain speculative. Some of the more extreme estimates (e.g. 15 km nucleus) are not yet broadly accepted. The Debrief+3Medium+3Medium+3

• Composition in detail
  While water ice and carbon dioxide have been detected, and gases like CO, carbonyl sulfide, etc., are suggested, the full inventory (organic molecules, isotopic ratios) remains under study. European Space Agency+3Sky at Night Magazine+3Planetary Society+3

• Origin in the galaxy / parent system
  It’s not known which star system or region this object came from; tracing the origin across galactic distances is very difficult. European Space Agency+3Planetary Society+3European Space Agency+3

• Exotic / non‐natural hypotheses
  Some have speculated (notably Avi Loeb) whether 3I/ATLAS might have some technological or non‐geological origin (i.e. alien artifact). These are speculative and controversial, and the mainstream interpretation remains that it is a natural interstellar comet.