Talk:3I/ATLAS: Difference between revisions – Wikipedia

“The comet will become reobservable from Earth by early December 2025.” If perihelion with Earth is on 19 December 2025, with the comet not visible, it can’t become visible again in early December 2025.

I think the intent is that it wont be visible at perihelion, then will become visible just before it passes closest to Earth. However, the wording (and placement after the statement about visibility from Mars) makes this section confusing. Someine with technical knowledge should rewrite for clarity. Mastakos (talk) 13:16, 4 July 2025 (UTC)[reply]

Perihelion is 29 October. I think you have misread this: “After perihelion, it will pass 1.83 ± 0.1 AU (274 ± 15 million km; 170.1 ± 9.3 million mi) from Earth on 19 December 2025,”. This part of the article is talking about closest approaches – to Mars, Earth & Jupiter. Perihelion is the closest approach to the Sun.EighteenFiftyNine (talk) 23:19, 4 July 2025 (UTC)[reply]

is it me and my chromebook but the article seems to change to a different font as the page opens – and not to my eyes a good one. Thanks Edmund Patrick – confer 15:22, 4 July 2025 (UTC)[reply]

Hi, that might have to do with Wikipedia’s general settings. Does this happen with other articles too? I think this could be because of the side panel that can be hidden – something similar sometimes happens on my comp too. Kmw2700 (talk) 17:06, 4 July 2025 (UTC)[reply]

Once you are logged in you can change the fonts as they appear in your user account settings, but you probably knew that already. Regards, Kmw2700 (talk) 17:08, 4 July 2025 (UTC)[reply]

i agree, I bought this up because it is the only page that the change happens to. Well at the moment Edmund Patrick – confer 19:06, 4 July 2025 (UTC)[reply]

Is it worth mentioning in the article that the comet passed about 5.1 ± 0.07 AU (763 ± 10 million km; 474.1 ± 6.5 million mi) from Pluto around 10 January 2023? (look for deldot = 0) — Kheider (talk) 17:51, 5 July 2025 (UTC)[reply]

Probably not. I don’t think Pluto is relevant here. Nrco0e (talk • contribs) 15:24, 6 July 2025 (UTC)[reply]

I see no relevance. Renerpho (talk) 17:44, 6 July 2025 (UTC)[reply]

@Kheider: 0.097 – 0.10: the rounded isn’t preferential as it isn’t accurate/real/true – there isn’t any necessity to round. (𒌋*𓆏)𓆭 18:04, 5 July 2025 (UTC)[reply]

Actually in the text of the article, I think readability is important for the general public. If we want that kind of precession it should be in the infobox. Besides, do we list 1-sigma, 3-sigma, or 7-sigma ranges? The general public knows little about all of that. — Kheider (talk) 18:08, 5 July 2025 (UTC)[reply]

You’re knowing 0.1 improves readability – this is a presumption. What evidence do you have that the general public wouldn’t be able to accept 0.097 – 1 more digit is greater complexity? As you stated “knows little about” – the fact of not knowing means the implications of a more difficult consideration in the science as shown by more digit e wouldn’t make any difference in the mind of the general public as the complete knowledge of how ranges of e complicate / strain thought of the actual science – the atrophysical implications – isn’t anything they would need think about – is only a number – indicating degree of uncertainty. I’m not an astrophysicist or astronomer: I find it bad that the rounded number is thought possible at all – because it is false. The rounded number simply isn’t the correct information. If it were a test – the correct answer is 0.097 (and the shown other digits). If the answer given was 0.1 the student would receive a fail. Not the same number. As a reader I look I see the number I integrate all the information into my mind while reading the article – I’m thinking the whole provision of information is valuable knowledge – a gift of university level information for those less fortunate – a sharing of information to improve all the species – i look at the source – I see wikipedia didn’t provide the source – it seems like betrayal – I find I can’t trust wikipedia. (𒌋*𓆏)𓆭 18:28, 5 July 2025 (UTC)[reply]

Basically – the whole rationalle in a scientific reasoning for rounded – seems correct – but in reality it’s simply madness to provide rounded – because there is no such number there. Look at the degree of measurement at the source. It is in 6 decimal places. Also I just rethought: perhaps it isn’t the general public and a scientist is reading the article – or a university student any other type more specialized entity. (𒌋*𓆏)𓆭 18:35, 5 July 2025 (UTC)[reply]

A 1-sigma uncertainty of 0.1 becomes a 3-sigma uncertainty of 0.3 no matter how many sigfigs one uses. — Kheider (talk) 18:54, 5 July 2025 (UTC)[reply]

Isn’t a response to my query. Your response doesn’t provide the necessary rebuttal of my criticism. Think instead like this perhaps: If i go to a bank – I withdraw $1’000’000 – the bank provides $1’000’000.01 or $999’999.99 is this a very probable situation? Do you think the exactness is important? (𒌋*𓆏)𓆭 19:04, 5 July 2025 (UTC)[reply]

How will anyone know the figure is rounded without looking at the source? They won’t – so – it’s just a bad provision – because it’s not the information – it is a fail. (𒌋*𓆏)𓆭 19:14, 5 July 2025 (UTC)[reply]

Regardless of what your personal opinion on the matter is, convention is to include errors at either one or two significant digits (in which case would be 0.1 or 0.10). The difference in a bank situation is that those numbers are by definition known absolutely- that is not the case in science, where values are uncertain and providing the -exact- value is meaningless when the error dwarfs it. The purpose of Wikipedia is to provide a comprehensible overview of a topic, not as a no-holds-barred full-precision repository of all data at all levels, no matter how infinitesimal. Those who want to know the EXACT errors to 1-in-100-level precision are able to go to the references, while here getting even an order of magnitude idea of the error (which this is still much better than) serves its purpose as a summary. exoplanetaryscience (talk) 08:36, 6 July 2025 (UTC)[reply]

Why are we deleting references about the size of the nucleus? There is no reason to think this faint comet is any larger than TWO kilometers in diameter at this time. It is not a non-active dark asteroid with a 20 km diameter! — Kheider (talk) 13:54, 6 July 2025 (UTC)[reply]

@Kheider: If you’re talking about this edit: We can argue about when preprints can/should be added as references (in most cases, we should wait for proper publication[1][2]), but this hasn’t even been accepted by Arxiv yet. Compare KyloRen2017‘s edit summary, Removed the unpublished reference from Loeb (which is most likely unreliable anyway). Loeb has a track record for being an unreliable source when it comes to interstellar objects in general.

Can we find a better source for the possibility of a small size? I agree with Kheider that that’s likely a correct conclusion. Renerpho (talk) 15:11, 6 July 2025 (UTC)[reply]

@Kheider: Do you have a source for the opposition surge (3I/ATLAS appears especially bright because the comet had passed opposition on 25 June 2025, causing its surrounding dust to be brightened by an opposition surge.^{[citation needed]})? I find no references that discuss this phenomenon in relation to 3I/ATLAS. Not even Loeb mentions it. I’d be surprised if backward scattering had a strong effect,[3] and the phase angle never dropped below 13.5° — way too large for the traditional opposition effect to be noticeable. Renerpho (talk) 17:54, 6 July 2025 (UTC)[reply]

I have read about it on some of the forums, but the best reference I can find with a quick look is: https://groups.io/g/comets-ml/message/33751 and may not be solid enough.– Kheider (talk) 20:33, 6 July 2025 (UTC)[reply]

I’ve removed it for now. If there’s a reliable source for this (and I’d argue a mailing list post doesn’t suffice), we can talk about adding it again. Renerpho (talk) 18:44, 9 July 2025 (UTC)[reply]

Non c’è nessuna modifica perché ogni variazione è generata da una deficienza artificiale 151.32.218.5 (talk) 05:05, 16 August 2025 (UTC)[reply]

@Onemillionthtree: I see you’ve added back the Loeb nucleus size estimate. I haven’t done a review of his calculations, so I can’t say if it’s trustworthy or not, but apparently some people (KyloRen2017) are very insistent on keeping Loeb out of here because he has a track record of making unreliable claims about interstellar objects. I’d like a second opinion on this. @Renerpho and Kheider:. Nrco0e (talk • contribs) 21:48, 6 July 2025 (UTC)[reply]

Loeb has both a very loud voice, and a rather bad reputation, making it difficult to determine the notability and the reliability of anything he says. However, we shouldn’t keep Loeb out of here if what he writes is determined to be trustworthy by the scientific community. What we can — and should — do is wait for his peers to review his writings. Let’s discuss this again when the paper has been accepted by Arxiv(!) published in a journal and has attracted some comments from other astronomers. Renerpho (talk) 22:09, 6 July 2025 (UTC) Changed the struck part, I think publication in a journal is a good standard in this case, where trying to determine the reliability of the author ourselves boils down to WP:OR. Renerpho (talk) 22:14, 6 July 2025 (UTC)[reply]

In the meantime, what should we do with this Loeb reference in this article now? Move it to the Size and brightness section? Get rid of it? Nrco0e (talk • contribs) 22:11, 6 July 2025 (UTC)[reply]

I think it should be removed for now. Renerpho (talk) 22:15, 6 July 2025 (UTC)[reply]

I’ve read a bit more into Loeb’s calculations. It seems like he assumes a single, fixed radius for every interstellar object for a given fixed interstellar object number density and a Galactic mass density. This calculation is too simplistic, as it ignores the fact that small bodies follow a size frequency distribution (i.e. interstellar objects become increasingly more common with decreasing radius). Estimating the interstellar object population is already a complex issue that has been tackled previously by big collaborations of prominent researchers like Matthew Payne, Michele Bannister, and Darryl Seligman, so I personally think we should wait it out on using the Loeb estimate as a reference. Nrco0e (talk • contribs) 22:17, 6 July 2025 (UTC)[reply]

“Harvard University” is a pro – but I think – cons: there isn’t any need to mention his name: if the individual is less than a stellar reputation – if he were Nobel or “genius” is would be worthy – all professors are authorities – no reason to name unless naming in the content is the consistent style – adds a “name” element with science data – implictly could suggest unproven validity. (𒌋*𓆏)𓆭 22:31, 6 July 2025 (UTC)[reply]

The effects of naming an author are complicated. I don’t think either adding or removing their name solves the problem. Renerpho (talk) 22:39, 6 July 2025 (UTC)[reply]

Just because Loeb is a professor in Harvard doesn’t mean he’s automatically reliable. He had previously (and still actively) claimed all of the known interstellar objects (especially ‘Oumuamua) were alien spacecraft, and he his claims have been refuted multiple times, despite what journalists like to report about it KyloRen2017 (talk) 22:43, 6 July 2025 (UTC)[reply]

KyloRen2017 is right. On the one hand, “Harvard University” is a pro is a valid argument. Loeb is a professor at Harvard, and that gives him some authority. It doesn’t make him a reliable source, but we wouldn’t be having this discussion if Loeb had published the paper on his personal website or blog, rather than his official personal Harvard website. That doesn’t make it a reliable source though: Scientists can’t just put their stuff on their website and circumvent peer-review like that. It’s all good making stuff available on a university website but it is no substitution for proper publication. This can be different if we determine Loeb to be a subject-matter expert, but I don’t think he qualifies, given the reputation he has among his peers. Renerpho (talk) 22:46, 6 July 2025 (UTC)[reply]

I would like it if the exact were retained=because “Harvard” but as a note – after “likely. [1]” From the perception then contemplation – input into consciousness of the subject-intro – I would like his name excluded from the view so I could process the data information without the need of Earthly-terrestrial concerns contra the transcendental aspects. “Loeb” is a 4 letter word: has a meaning – the input of the name creates a digressive/distracting unconscious/subconscious association perhaps – seeing the word-form – unscientific thoughts are created by sight – is a greatly meaningless identifier not scientific data in perception. (𒌋*𓆏)𓆭 22:51, 6 July 2025 (UTC)[reply]

@Onemillionthtree: No offense, but I have no idea what you’re trying to say. Could you try to explain your arguments again, this time referencing Wikipedia guidelines and policies rather than… whatever you’ve been referencing? Renerpho (talk) 23:00, 6 July 2025 (UTC)[reply]

I meant – simply as a stylistic observation – inc. a name adds information which isn’t exactly subject related – a human’s name – isn’t data – information on the title-subject: I don’t have any relevant policy to indicate on this first direction. With regards to your recent article change of re-exclusion of the complete sentence after a decision of 23:0 by a Talk un-involved editor – that editor’s reasons were valid: the source shows “<” as one of two options which are mutually exclusive. The precedence of that reason – I solved with “possibly”. I think the argument here: somehow Loeb’s argument isn’t valid: isn’t shown by any source – so isn’t valid – is only wikipedians opinion. Loeb has an unchallenged position in a university, the critique of his opinions here aren’t valid cause to act against without a contrary source also of university orign. His perceived bad reputation isn’t a scientific proof – isn’t proof his science is bad – thinking: “bad in the past” therefore “bad in the now”. It is the work of editors to show sources which are “reliable” etc not devalue on the basis of probability of bad / wrong without proof. (𒌋*𓆏)𓆭 23:43, 6 July 2025 (UTC)[reply]

That is not sufficient reason (and wildly out-of-topic) to keep Loeb’s claims regarding 3I/ATLAS. The main issue here is that his findings were not yet published and peer-reviewed as of today, not just because of his name. KyloRen2017 (talk) 00:42, 7 July 2025 (UTC)[reply]

By the form of the word: dis-covered I would think the application is i.e. archaeology or metal detecting – in the context of machine telescopes and auto-processes i.e. “ATLA-System station” would be the latter – i.e. the discoverer was ___name of someone___, not type of machine : a detecting machne, or, a detector; not the machine was a discoverer – this is currently also shown within the link ATLAS “early warning system optimized for detecting”. (𒌋*𓆏)𓆭 07:11, 8 July 2025 (UTC) Det. is neutral – as a retinal input – receiving a signal : disc. is not neutral – implication of good/bad – discovered treasure or scientific improvement / a crime (the prev. unknown event of) (𒌋*𓆏)𓆭 07:19, 8 July 2025 (UTC)[reply]

ATLAS is the discoverer, with all the implications that entails. It’s what the initial announcement says,[4] as well as a large majority of reliable sources. It’s also standard phraseology for newly found comets. Renerpho (talk) 09:21, 8 July 2025 (UTC)[reply]

Does anyone have the skills and data to produce an animation of 3I/ATLAS passing through the solar system, showing its proximity to the orbiting Earth, Mars, Jupiter and so on? It would be interesting to see this. Wavehunter (talk) 16:36, 9 July 2025 (UTC)[reply]

@Wavehunter: You mean something like this? Annotations in the lower left corner with time, velocity, distance from Earth and Sun, and the two close approaches to Mars and Jupiter. (Need to click on the video, and then click again to start the animation.) Renerpho (talk) 01:14, 10 July 2025 (UTC)[reply]

@Renerpho: Can you make a gif version where the camera isn’t spinning? Nrco0e (talk • contribs) 05:37, 10 July 2025 (UTC)[reply]

Sure! I’ll make one and add it as an alternative version. Is it necessary to turn it into a gif, rather than a webm video? Renerpho (talk) 10:19, 10 July 2025 (UTC)[reply]

@Nrco0e: I have added two versions. Version 2 is similar to the first but without rotation. Version 3 is looking at the Solar System from above, and is running at slightly slower speed. Version 4 is the same as 3, but as a GIF rather than a web movie. Renerpho (talk) 11:21, 10 July 2025 (UTC)[reply]

They all look great and show how close (relatively) the object will fly past Mars. Thank you. —Wavehunter (talk) 15:51, 10 July 2025 (UTC)[reply]

I’ve added version 4 to the article. Renerpho (talk) 20:19, 10 July 2025 (UTC)[reply]

The media has news reports about the origin of the comet, but there’s no mention in the article. 105.9.94.73 (talk) 17:35, 11 July 2025 (UTC)[reply]

Agreed – if any astronomers have given speculations about where the comet formed / point of origin, that would be interesting to include. 2603:6080:21F0:6260:9801:67B3:FCB0:AB4D (talk) 09:52, 12 July 2025 (UTC)[reply]

The BBC quotes an Oxford University astronomer who believes it originated in the thick disk of the Milky Way. Reference here. —Wavehunter (talk) 18:53, 12 July 2025 (UTC)[reply]

The probable origin in the thick galactic disk is mentioned in the article (and has been for over a week). Renerpho (talk) 21:06, 12 July 2025 (UTC)[reply]

This edit request has been answered. Set the |answered= parameter to no to reactivate your request.

Hiparcis asit (talk) 15:05, 15 July 2025 (UTC)[reply]

Add the following information:

The first spectroscopic data, obtained at more than 4 astronomical units, indicate that this is a reddish object (consistent with the spectral slopes of D-type asteroids), much redder than 2I/Borisov. Although the object clearly shows activity, only upper limits to the production rates of OH and CN can be estimated: 8.0 × 10²⁴ s⁻¹ y 4.9 × 10²³ s⁻¹, respectively.

https://arxiv.org/abs/2507.07312

 Not done: The page’s protection level has changed since this request was placed. You should now be able to edit the page yourself. If you still seem to be unable to, please reopen the request with further details. UmbyUmbreon (talk) 02:21, 17 July 2025 (UTC)[reply]

I’m not sure if these are notable (as alternative designations, or otherwise), but 3I/ATLAS has appeared an additional six times on the NEO Confirmation Page since its discovery:

1. 3I = A11pl3Z (July 2.90 UT) – The initial discovery
2. 3I = A11psVj (July 3.52 UT) – NEOCP log
3. 3I = or08008 (July 4.54 UT) – NEOCP log
4. 3I = ABC0003 (July 5.12 UT) – NEOCP log
5. 3I = K5a01Ii (July 7.99 UT) – NEOCP log
6. 3I = K5pc1JY (July 9.85 UT) – NEOCP log
7. 3I = 5GG1921 (July 17.44 UT) – NEOCP log
8. 3I = K6J91Is (July 19.50 UT) – NEOCP log

Some of these are targeted follow-up; some like 5GG1921 appear to be independent (re)discoveries. The MPC, it seems, still isn’t quite ready to deal with very eccentric orbits. Renerpho (talk) 11:32, 17 July 2025 (UTC)[reply]

It is definitely worth noting on the talk page while our memories are fresh. — Kheider (talk) 12:56, 17 July 2025 (UTC)[reply]

@Kheider: Good idea. I’ve just added number 8 to the list. Renerpho (talk) 18:56, 20 July 2025 (UTC)[reply]

…for 21 July 2025, with a zero month proprietary period “so the observations can be of maximum benefit to the community”

What does this mean? What’s a zero month proprietary period? and the rest of the statement seems to be pure journalism, which you can delete without information loss. Keichwa (talk) 20:52, 17 July 2025 (UTC)[reply]

@Keichwa: Hubble images (like most professionally taken astronomical images) are generally proprietary for some time, usually for a period of 12 months, during which only the researchers who proposed the observations have access to the data. They can use that time to analyze it and publish their results. After that, the data becomes freely available; it is put into the public domain, where everyone can access it and do with it whatever they want (including make new discoveries).

By giving up their right to a proprietary period, the researchers here are making that data available to everyone immediately.

By the way, “so the observations can be of maximum benefit to the community” is a quote from the researchers who proposed those observations, not from some journalist. It is in the official proposal made to NASA. Renerpho (talk) 21:11, 17 July 2025 (UTC)[reply]

The first two Hubble images, taken about 4 hours ago, are now available.[5] Renerpho (talk) 21:14, 21 July 2025 (UTC)[reply]

Quite a lot to unpack, and to update from this new paper about Vera Rubin’s precovery of 3I. I don’t have time right now, just putting this here for me to do it later, if nobody else already has: [6] Renerpho (talk) 13:16, 21 July 2025 (UTC)[reply]

I’ve added bits about the Vera Rubin Observatory’s observations to the article. Most of the paper’s contents are focused on the Vera Rubin Observatory’s performance, so hopefully that eases anyone if the paper’s size is overwhelming. Nrco0e (talk • contribs) 02:26, 22 July 2025 (UTC)[reply]

Thank you! Renerpho (talk) 22:07, 23 July 2025 (UTC)[reply]

have any suitable pictures that can be included? 文爻林夕 (talk) 09:17, 26 July 2025 (UTC)[reply]

Quote from the article: … the highest eccentricity of any Solar System object currently known …

I’m not sure if the link to List of Solar System objects is appropriate in this case. It is not a Solar System object, because it isn’t bound to the Sun, and that list doesn’t mention interstellar objects; but what is it? Renerpho (talk) 22:07, 23 July 2025 (UTC)[reply]

I removed the statement as solar objects such as C/1980 E1 (Bowell) that “orbit” the Sun with an eccentricity of ≈1 seem a little off topic for the trajectory of 3I/ATLAS. If anything it could be a footnote. — Kheider (talk) 09:33, 24 July 2025 (UTC)[reply]

@Kokoo: I’ve removed the “Hypotheses of artificial origin” section, as it is giving undue weight to a WP:FRINGE theory. However, if you want to help work on a new “origin” section, I think a sentence or two about this are in order! We can work on it together on this talk page if you like. Renerpho (talk) 22:54, 25 July 2025 (UTC)[reply]

Loeb’s alien spacecraft speculation pre-dates the new Hubble observations of 3I/ATLAS and his statements have criticism from other astronomers, which have been mentioned in news articles too. These must be addressed too. Here’s some examples:

• https://www.livescience.com/space/extraterrestrial-life/here-we-go-again-controversial-paper-questions-whether-interstellar-visitor-3i-atlas-is-possibly-hostile-alien-tech-in-disguise
  • “The researchers described the new paper as a “pedagogical exercise,” or thought experiment, and offer no clear evidence of alien involvement. Instead, they point at the comet’s “anomalous characteristics” and provide alternative theories to explain them.”
  • “Given the available evidence, many of the researchers who spoke to Live Science are disappointed with the new paper and pointed out that it distracts from the work of other scientists.”
  • “There have been numerous telescopic observations of 3I/ATLAS demonstrating that it’s displaying classical signatures of cometary activity,” Darryl Seligman, an astronomer at Michigan State University who led the first study quantifying 3I/ATLAS, told Live Science in an email.
  • “All evidence points to this being an ordinary comet that was ejected from another solar system, just as countless billions of comets have been ejected from our own solar system,” added Samantha Lawler, an astronomer at the University of Regina in Canada who specializes in solar system dynamics.
  • Any assumptions about the object’s lack of volatiles is also premature at this time. “The object is still pretty far away from the sun, so no, we wouldn’t typically expect to find direct evidence of volatiles necessarily,” Seligman said. Instead, these compounds will likely become apparent in the coming weeks and months, he added.

…okay, well this is the only news article I can find. Most astronomers’ responses to Loeb are via posts on the Bluesky social media platform. It should be noticed that news media VERY OFTEN share ONLY ONE SIDE of the story and will tend to choose the most clickbaity headlines, which is why you don’t see many articles weighing in on the opinions of both Loeb and other astronomers. Many of the new media covering Loeb’s idea (Newsweek, Daily Mail, New York Post, Futurism, etc.) are not reliable because they do not specialize in the academic side of astronomy and thus do not have the relevant expertise to be accurate. Reliable news media for academic astronomy (from what I’ve seen) include Universe Today, Space.com, Live Science, IFLScience, EarthSky, Sky & Telescope, organization press releases, etc. And of course, Loeb will inevitably decry “other astronomers” and us for challenging his outlandish claims. But anyways, right now I’m busy and am not in the mood to deal with this right now. Nrco0e (talk • contribs) 23:14, 25 July 2025 (UTC)[reply]

Loeb’s attention-seeking-rubbish should not be in the article. — Kheider (talk) 10:05, 26 July 2025 (UTC)[reply]

@Kheider: Loeb’s attention-seeking rubbish is getting quite a bit of attention, and is clearly notable by this point. The best we can do is to try and cover it neutrally and briefly, and point to the responses from other astronomers along the way. Renerpho (talk) 10:36, 26 July 2025 (UTC)[reply]

Loeb will inevitably decry “other astronomers” and us for challenging his outlandish claims. – He already has done so, compare his blog post on Medium from July 12th. To quote the part about Wikipedia:[7]

Needless to say, when the details of 3I/ATLAS were summarized on Wikipedia a few days after its discovery, the editors of that entry omitted any reference to anomalies of 3I/ATLAS. They learned about my paper from colleagues on July 4 but responded that this paper must be published in a journal before being referenced on Wikipedia. For context, the Wikipedia site for 3I/ATLAS included at that time only references to unrefereed scientific announcements and news reports. This practice by the Wikipedia gatekeepers provides yet additional evidence for the thesis presented in a new paper that I posted with the psychologists Omer Eldadi and Gershon Tenenbaum on July 9, explaining the psychological reasons for the suppression of paradigm-breaking evidence by the scientific community.

This is, of course, twisting the story quite a bit. In any case, Loeb’s blog should not be considered to be a reliable source. If this turns into an actual controversy, rather than someone just crying about being ignored, we can talk about whether it’s worth covering. Renerpho (talk) 10:50, 26 July 2025 (UTC)[reply]

At least nowadays, more recent observations strengthen the fact that 3I/ATLAS is an actual comet rather than a large alien spacecraft as Loeb actively insists KyloRen2017 (talk) 11:59, 26 July 2025 (UTC)[reply]

I was always ok with including his nucleus size estimates, but claiming 3I might be alien because we can not prove it not a cloaked Death Star is merely self-promotion for his business. — Kheider (talk) 15:20, 26 July 2025 (UTC)[reply]

We are kinda having the same type of discussion on the french wikipedia article of 3I/ATLAS. There doesn’t seem to be a consensus yet on if and how we should mention his ‘educational’ thought experiment, but Loeb only needs to publish “preprints” articles every time an unusual scientific discovery is made for it to be mentioned on Wikipedia. Seeing him question why he is not mentioned in an Wikipedia article shows that he is more interested in business and getting people to talk about his books than in what he contributes to the scientific community. Thank you all for having this discussion here, interesting points of view from each side. DobbAY (talk) 01:13, 27 July 2025 (UTC)[reply]

Thanks for telling us about what’s going on in the French Wikipedia. I haven’t seen what’s going on other languages, but now that I look at the French wiki page for 3I/ATLAS, I think it’s very problematic that Loeb’s wild statements go unchallenged without mentioning criticism. This absolutely not representative of the situation! A lot of astronomers are very upset about this—see Jason Wright‘s blog describing the Loeb situation and how (upsettingly) silly it is: https://sites.psu.edu/astrowright/2025/07/18/avi-and-3i-atlas/

Well, any blog or Bluesky post aren’t reliable sources because they’re primary sources by Wikipedia standards, but still. The Live Science news article is the only article I could find (so far) that reasonably covers both sides of this controversy. Nrco0e (talk • contribs) 01:52, 27 July 2025 (UTC)[reply]

I agree, we have to be careful to not let Loeb’s claim go unchallenged, even if the media is doing a less-than-optimal job covering the story. Wikipedia is there to reflect current knowledge, which means we need to follow what reliable sources are saying — but that doesn’t mean we have to parrot nonsense. Renerpho (talk) 12:03, 27 July 2025 (UTC)[reply]

Probably a section regarding the alien origins theory should not be 15% theory and 85% criticism. If its a section called “Critique of alien theories” then fine. 2400:2410:B3E1:4300:ECC9:8DC9:FF62:6A5D (talk) 02:07, 10 October 2025 (UTC)[reply]

I’m fine with making it 90% criticism. Renerpho (talk) 03:01, 10 October 2025 (UTC)[reply]

At this point, the odds of 3I/ATLAS being “Alien Tech” are about 1 in a million. Let me know when the mother-ship parks between Earth and the Moon. — Kheider (talk) 09:15, 10 October 2025 (UTC)[reply]

I am fine with criticism, but I’d rather see all these items on Loeb’s page, rather than on all the dedicated objects he claimed to “potentially be artificial”. Perhaps there could be a redirection to the specific chapter on Loeb’s page. It hurts to see all these interesting and unique objects, because they are the first to be discovered, being polluted by someone who is trying to sell his books and get paid for conferences. DobbAY (talk) 17:35, 10 October 2025 (UTC)[reply]

I agree to this proposal. It is honestly sickening and painful that a professional astrophysicist is the one who intentionally misinforms people about claiming such objects as simply aliens, without consulting to other astronomers who are actively studying these objects in detail KyloRen2017 (talk) 17:58, 10 October 2025 (UTC)[reply]

I would like to point to somewhere on Wikipedia that covers Loeb’s ideas about interstellar objects in general, or at least to similar discussions that have been had before. That context is missing at the moment. What do you think about adding {{see also|1I/ʻOumuamua#Technosignature hypothesis}} to the 3I/ATLAS#Alien spacecraft controversy section? Renerpho (talk) 11:59, 27 July 2025 (UTC)[reply]

Okay, we have another secondary source covering the controversy with both perspectives: https://earthsky.org/space/3i-atlas-3rd-interstellar-visitor-alien-probe/

(post comment edit: nevermind, this article is one-sided BS like many others. Sigh…)

And yes, I think it’s a good idea to give context that Loeb is controversial and has made similar claims in the past. Nrco0e (talk • contribs) 17:37, 27 July 2025 (UTC)[reply]

Loeb has written books and papers on this subject which has received lots of commentary, it should be no problem creating an article on the general hypothesis. If aliens exist in the galaxy or universe, we could find them indirectly ie. through garbage. This is perfectly reasonable for example SETI is looking for stray radio signals. Why not stray chunks of discarded alien hardware? Instead of digging up broken pottery shards of lost civilizations, we are investigating pieces of interstellar debris occasionally flying through the solar system for the possibility of alien garbage. It’s a hypothesis, a “testable prediction”. — GreenC 05:43, 28 July 2025 (UTC)[reply]

@GreenC: The idea itself (to look for signs of alien life in interstellar objects) is fine. The problem is that Loeb’s approach to this is entirely unscientific. What he calls a “testable prediction” in his recent arxiv upload is no prediction at all, it’s a bunch of easily refutable claims. Renerpho (talk) 07:22, 28 July 2025 (UTC)[reply]

Put simply, the claim of it being alien tech is so ridiculous as to be off-topic in an article about a comet that becomes more active when it is inside the orbit of Jupiter. Soon the orbit solution might include parameters A1, A2, and A3 as does 2I. That will mean we know roughly how actively it is outgassing as it becomes more active. It will not mean it is alien tech. — Kheider (talk) 11:49, 28 July 2025 (UTC)[reply]

Loeb is not “claiming” alien tech. He made a hypothesis that is testable based on a rational theory. Wikipedia covers all aspects social and cultural. Even if we completely discount Loeb’s hypothesis as exceeding the bounds of the scientific method (does it have bounds?), for better or worse, his part of the story has become notable. Usually the best approach is to state his hypothesis then essentially discount it. This sort of thing happens frequently on Wikipedia, particularly with popular conspiracy theories. — GreenC 15:38, 28 July 2025 (UTC)[reply]

@Kheider: I’m with GreenC here. It doesn’t matter if we personally consider Loeb’s hypothesis “rational” (or even doubt that he’s acting in good faith). The best way to deal with his ideas is to state them as they are, as briefly as possible but as long as necessary, and refute them thoroughly using the few reliable sources we have for that. Even if the media are doing a bad job at covering both sides of this debates fairly, we can still do so. Renerpho (talk) 21:04, 28 July 2025 (UTC)[reply]

https://www.youtube.com/watch?v=4nYXIeZh_bw gives a 45-minute summary of what’s wrong with Loeb’s ideas, concentrating on 1I/’Oumuamua and 3I/ATLAS, and the alleged interstellar meteor CNEOS 2014-01-08. One could add the easily refutable claim that the asteroid 2005 VL1 was a spacecraft as an example of Loeb being uninterested in the opinion of experts in the field: The refutation in this case comes from Jonathan McDowell, the expert on artificial objects in space, who works in the same department as Loeb, on the same floor — and who Loeb of course had not consulted before making some outlandish claim. What all of these incidents have in common is that they are made in willful ignorance, paint him as a martyr fighting the “establishment”, and circumvent the process of peer review wherever possible. Renerpho (talk) 20:42, 30 July 2025 (UTC)[reply]

I agree, there is always someone who will label any object in the sky as being artificially made. Gamnacke (talk) 12:08, 15 October 2025 (UTC)[reply]

To make things clear for future editors, 3I/ATLAS still has a coma. Somehow Avi Loeb misinterpreted the “lack of a tail” statement in Santana-Ros et al. (Aug 2025) as evidence against cometary activity, despite the fact that the authors explicitly state that 3I/ATLAS has a coma and make analyses relevant to comets (i.e. dust production rate, dust cross-section, etc.). Keep an eye out for misleading public statements—see Jason Wright‘s blog documenting Loeb’s daily commentary on 3I/ATLAS. Nrco0e (talk • contribs) 03:11, 5 August 2025 (UTC)[reply]

IMHO, it should be mentioned in the lead that the comet will pass within 0.2 AU of Mars and that Mars is the (major) planet it comes closest to. I doubt the value of mentioning that it’s the 3rd interstellar detected. That is probably noteworthy enough to be included, just not in the lead.
I also wonder if the trajectories shown in the animations are correct. My very little experience is that Jupiter is quite significant in ballistic trajectories in the inner solar system and this comet passes <0.4 AU from Jupiter yet I see no obvious deviation in its path? This likely is because the perturbation is minor and “invisible” at the scales shown, but maybe someone can verify that the model has taken Jupiter’s gravity well into consideration – I’d just have expected a bit more deviation after its “close encounter” with Jupiter…but I’m far too ignorant to claim it “should” (or shouldn’t) show visible perturbation.98.22.50.44 (talk) 21:35, 7 August 2025 (UTC)[reply]

The fact it is only the 3rd known interstellar object is significant. The Mars approach is not gravitationally significant and that is why it is not listed on the JPL SBDB. Even the Jupiter approach will not show a change in trajectory at the scale used. The model used even accounts for the 16 largest asteroids. Keep in mind because this object is moving so fast, it does not spend much time near any one object. — Kheider (talk) 22:04, 7 August 2025 (UTC)[reply]

Indeed, the JPL ephemerides and trajectory shows that Jupiter’s gravity doesn’t noticeably deflect 3I’s trajectory. Though it is worth nothing that the Catalina Sky Survey (CSS) trajectory diagrams used in this article do not simulate the gravity of other planets (not an n-body simulation), so the CSS diagrams aren’t exactly accurate. But you probably won’t notice any obvious differences anyway, since the gravitational deflections aren’t that noticeable in reality either. Nrco0e (talk • contribs) 22:08, 7 August 2025 (UTC)[reply]

To anyone who is watching, there is a problem with some of what we write in interstellar object, per Talk:Interstellar object#Torbett (1986) is not a good reference. That article has some overlap with this one, so maybe you’re interested and can help. Thanks! Renerpho (talk) 23:08, 15 August 2025 (UTC)[reply]

@Kheider: I’m not sure about adding the CO2 coma diameter to the infobox. I’m worried that inserting it there might end up misleading or confusing readers, since the article doesn’t mention coma size until much later in the coma section. Would it be better to simply remove the CO2 coma diameter from the infobox, or include it with extra steps like, like labeling the nucleus and coma diameters as:

Nucleus: xxx km
Coma: xxx km

and then mention the coma diameter somewhere in the article lead? Nrco0e (talk • contribs) 17:07, 24 August 2025 (UTC)[reply]

I like the idea of listing both in the infobox given the extreme “speculation” about this comet. — Kheider (talk) 19:14, 24 August 2025 (UTC)[reply]

The introduction is misleading, suggesting that the solar system begins at 4.5 AU, when saying it was “entering the inner Solar System at a distance of 4.5 AU.” 50.70.39.132 (talk) 18:38, 29 August 2025 (UTC)[reply]

Fair enough. Would it be better if it was written as “heading toward the Solar System at a distance of…”? Nrco0e (talk • contribs) 18:42, 29 August 2025 (UTC)[reply]

The INNER Solar System starts inside the orbit of Jupiter where the rocky planets are located. The statement is correct. — Kheider (talk) 19:18, 29 August 2025 (UTC)[reply]

Kheider is right. The linked page inner Solar System isn’t misleading either, defining it as the region “within the frost line, which is a little less than 5 AU from the Sun”. Renerpho (talk) 02:18, 30 August 2025 (UTC)[reply]

There’s a section with I guess a typo that needs correction for clarity. The article says “Even at its peak brightness, the comet will not be visible to an observer on Earth using the naked eye an observer with a pair of 70 mm binoculars.” Should there be an _or_ between “naked eye” and “an observer”, or will it be visible with 70 mm binoculars? Either way, could someone fix this? Lexicon (talk) 07:25, 12 September 2025 (UTC)[reply]

Oops. Yes, there should be an “or” in there. 3I/ATLAS is really a common faint comet largely due to the fact it never gets closer than 1.3AU from the Sun. (Most news-worthy comets pass within 0.5 AU of the Sun which allows them to become much more active.) Unless there is a notable spike (outburst) in the brightening curve, this comet will require an experienced observer with at least a 150–200 mm (6–8 in) scope to visually detect. But like all publicly-promoted comets, there will be numerous members of the public that confuse a common contrail for it. — Kheider (talk) 09:51, 12 September 2025 (UTC)[reply]

Is this a RS for our purposes? <– archive URL

Do we have any record, ever, if this is accurate… a CME aligning with a comet? — Very Polite Person (talk/contribs) 17:42, 26 September 2025 (UTC)[reply]

A CME hit comet 2P/Encke on 2007 October 3. It is not uncommon. — Kheider (talk) 18:33, 26 September 2025 (UTC)[reply]

I came here bc of “The Sun Just Directly Hit 3I/Atlas With A Coronal Mass Ejection. I knew our boy The Sun would have our back. Get fucked weird rock,” which I suppose you’ll be hearing about soon enough.

I’ve been lingering around Wikipedia for a looooong time and I am pleased that I have retained the ability to be dazzled. This space thingy (comet?) was discovered in July and look what you all have manifested in a few short weeks. The graphics! The charts! The showing-your-work math formulas in the explanatory notes! The tiers of analysis! What a lovely effort and superlative result. I am so proud of you all who have collaborated bringing your various skills and interests to bear in this article. Well done.

THANK YOU.

jengod (talk) 02:07, 28 September 2025 (UTC)[reply]

@Jengod: A sincere thank you, on behalf of Kheider, Renerpho, and the countless editors who made minor edits to this article! I’m gonna be honest, as one of the biggest contributors to this article, I’ve been expanding this article mainly out of spite against the rampant “not a comet” misinformation and aliens sensationalism propagated by the media and public (I mean… look at the absurd amount of IP vandalism on this article!), who keep misconstruing Avi Loeb’s “open minded” statements about 3I/ATLAS. Besides aliens, I don’t understand why the media keeps turning to Loeb (who doesn’t bother collaborating with 3I/ATLAS and comet researchers for some reason… see Jason Wright’s blog documenting this fiasco) instead of other astronomers who are *actually* actively studying 3I/ATLAS with telescopes instead of idly contemplating about it. And yes, I’m gonna make it clear that the top 3 biggest contributors to this article, including me, are biased against Avi Loeb, even though we try to keep the article as neutral as possible per Wikipedia policy (and oftentimes that doesn’t work, so we welcome other editors to step in).

Anyways, I’ll end my rant and instead gush about the graphics used in this article—I’m am SO SO SO grateful that the astronomers are publishing their papers and figures on arXiv under a CC-BY-4.0 license that Wikipedia can use! Even if these plots contain juicy scientific data highly relevant to the stuff mentioned in the Wikipedia article, they never get used news stories ever, because plots are generally a big no-no in public science communication unfortunately. And by the way, I should give a quick shoutout to User:Thunkii for making the sky chart for 3I/ATLAS in the Observability section!

Unfortunately, with me being in college and hyperfixating on other stuff right now, the article is a bit out of date (I still haven’t added that one arXiv study about ZTF’s 3I/ATLAS precoveries yet) and I don’t know if I’ll have time to continue updating this article as I did a few months ago. I’m hoping the hype on 3I/ATLAS dies down so that I have less things to fix by the time I return to this article. Nrco0e (talk • contribs) 03:20, 28 September 2025 (UTC)[reply]

Bro, one of my favorite sayings is “through spite, all things are possible” (it fuels a lot of good content around here), so rock on. The hype will indeed die and your weird rock will be left in peace. Cheers jengod (talk) 03:26, 28 September 2025 (UTC)[reply]

I’m busy and don’t have time to edit this article nowadays, so I’d appreciate it anyone is willing to update this article with the following papers that haven’t been referenced/discussed yet:

I’ve also heard from Bluesky and the groups.io comets mailing list that 3I/ATLAS is apparently now green due to C
₂ emission and is experiencing a CME, but I haven’t checked those in detail yet. If there’s news reports about these, please do add them in too.

Just in case, pinging @C messier, Kheider, KyloRen2017, and Renerpho: if any of you are interested.
Nrco0e (talk • contribs) 05:13, 1 October 2025 (UTC)[reply]

this one also looks interesting:

As seen from Mars, the Martian moon Phobos (magnitude −8.3) is around 3 million times brighter than 3I (magnitude ~8) at Mars. — Kheider (talk) 17:44, 6 October 2025 (UTC)[reply]

@Kheider: Oh gosh, there’s already misinformation going around about Perseverance’s images of 3I/ATLAS now? Oh wait, it came from Loeb. How surprising. Nrco0e (talk • contribs) 20:26, 6 October 2025 (UTC)[reply]

Yes, many on social media are confusing an elongated (star-trailed) image of Phobos for 3I/ATLAS. — Kheider (talk) 16:21, 7 October 2025 (UTC)[reply]

Can’t really talk about it until we get some coverage in RS though.©Geni (talk) 16:27, 7 October 2025 (UTC)[reply]

The annotated Perserverance mast-cam image in the gallery is sourced to Simeon Schmauß, who has since acknowledged it shows Phobos and not 3I/ATLAS. See https://bsky.app/profile/stim3on.bsky.social/post/3m2khsfby222h . Please remove it, barring actual notable sources. —31.150.26.109 (talk) 08:43, 17 October 2025 (UTC)[reply]

In the article is the fuzzy coma of a faint magnitude 8 comet. Simeon is talking about Phobos being a bright oblong tic-tac (all by itself) which is not included in this article.

https://www.esa.int/Science_Exploration/Space_Science/ESA_s_ExoMars_and_Mars_Express_observe_comet_3I_ATLAS

Can we drop this into the exploration section or do we need to wait for third party coverage.©Geni (talk) 16:27, 7 October 2025 (UTC)[reply]

In a scientific article, yes, that is as reliable of a source as you will get. — Kheider (talk) 16:54, 7 October 2025 (UTC)[reply]

I just want to ask about more reliable sources for information. You know mainly to avoid the aline hype and junk. Casue I won’t lie I think it’s getting worst. ZaWAHdo (talk) 12:14, 16 October 2025 (UTC)[reply]