[HN Gopher] Interstellar Object 3I/Atlas Passed Mars Last Night
       ___________________________________________________________________
        
       Interstellar Object 3I/Atlas Passed Mars Last Night
        
       Author : jandrewrogers
       Score  : 176 points
       Date   : 2025-10-03 20:40 UTC (1 days ago)
        
 (HTM) web link (earthsky.org)
 (TXT) w3m dump (earthsky.org)
        
       | pelagicAustral wrote:
       | Was it glowing green?
        
         | ares623 wrote:
         | Ulaaaaa!
        
       | suprnurd wrote:
       | Looking forward to seeing what images they received, especially
       | after Avi Loeb's comments on it.
        
         | ares623 wrote:
         | Avi's the new "it's Aliens" meme guy
        
           | zikzak wrote:
           | No, he's the new "we should consider what this would look
           | like if it were an artifact of an alien civilization" guy.
           | You know, open minded.
           | 
           | He's also a well respected and very accomplished person who
           | has acknowledged this is a comet.
           | 
           | If it happens to slow down and change trajectory after it
           | passes behind the sun, he might change his tune but he's
           | pretty focused on the science at this point.
        
             | ceejayoz wrote:
             | He _was_ well respected. As the saying goes, open your mind
             | too far and it falls out of the cranium.
        
               | zikzak wrote:
               | Um, ok. I think he's still doing ok and his fellow
               | academics would prefer he didn't openly speculate about
               | pet theories. They think it is embarrassing.
               | 
               | But ask yourself where we'd be if noone ever asked what
               | if.
               | 
               | There's a reason he called his project to observe
               | anomalous phenomenon The Galileo Project. Ring a bell?
        
               | ares623 wrote:
               | Didn't Galileo collect evidence first?
        
               | ceejayoz wrote:
               | > There's a reason he called his project to observe
               | anomalous phenomenon The Galileo Project. Ring a bell?
               | 
               | Sure, like the Patriot Act was about patriotism.
        
               | alganet wrote:
               | "What if it's an alien artifact?" - We're going to
               | observe it.
               | 
               | "What if it's a natural object?" - We're going to observe
               | it.
               | 
               | That's it. It's all we can reasonably do for now. It
               | changes nothing.
        
               | exe34 wrote:
               | Very little observing involves just the eyes. much of
               | what we observe relies on millennia of assumptions. if we
               | don't consider alternatives that we would normally reject
               | out of hand, we can miss things.
        
               | alganet wrote:
               | Space agencies are already pointing every single
               | instrument they can at this thing.
        
               | exe34 wrote:
               | I bet the aliens are having an annual picnic in the
               | opposite direction!
        
               | all2 wrote:
               | There's an excellent quote from the WH40k universe:
               | An open mind is like a fortress with its gates unbarred
               | and its walls unguarded.
        
               | exe34 wrote:
               | that's not what an open mind is though. an open mind is
               | one that is willing to question what is inside as much as
               | it is willing to question what is outside.
               | 
               | a side effect of questioning what is inside leads to
               | allowing some of what is outside in.
        
               | ares623 wrote:
               | My favorite piece of media is Contact (book and movie).
               | 
               | Ellie is someone I would consider having an open mind.
               | She dedicates her work, at great risk to her own career,
               | finding signs of extraterrestrial life. Despite everyone
               | telling her not to waste time and resources on it. But
               | she does and she does it by collecting the evidence
               | first, and when she got it, double and triple checked it
               | before making the announcement.
               | 
               | Avi kind of does the opposite. He hypes his ideas up
               | first, often taking credit for others' work, without
               | sufficient evidence.
        
               | andrei_says_ wrote:
               | One of my other favorite piece of media is the intro of a
               | Rick and Morty episode parodying the plot of contact.
               | Highly recommended.
        
               | ares623 wrote:
               | I missed that. I'll have to look it up.
        
               | philbo wrote:
               | I think 3I/Atlas is a comet.
               | 
               | But I also think the question "what if it wasn't" is
               | useful to consider.
               | 
               | I'd label anyone unwilling to discuss that topic a crank,
               | not the other way round.
        
               | ceejayoz wrote:
               | "What if" is just fine.
               | 
               | Loeb goes quite a bit further than that.
        
               | philbo wrote:
               | Does he though? Honestly I haven't seen it.
               | 
               | I've been through the last ~10 or ~15 posts on his Medium
               | this evening, to check. Sentence-by-sentence I don't see
               | anything that goes beyond "what if". Can you share some
               | of the quotes you have in mind?
               | 
               | I think this is an interesting phenomenon, because it
               | seems that lots of people throw personal insults at him
               | (not saying that's you btw) without addressing the meat
               | of whatever they're reacting to.
               | 
               | And lest we forget! One of the founding essays [1] of
               | this very website discusses it: if you're slinging ad
               | hominem attacks or personal insults around, you're by
               | definition losing the "argument" (not that I think this
               | qualifies as an "argument").
               | 
               | [1]: https://paulgraham.com/disagree.html
        
             | phyzome wrote:
             | Last I checked, he was making claims well beyond that.
        
               | xorbax wrote:
               | "What if 3I/Atlas is responsible for the Wow! Signal?!"
               | is one of the sillier ones
               | 
               | He's definitely turned into a "I'm just asking questions
               | and keeping an open mind" kinda grifter, whatever his
               | past qualifications and respectability
        
               | bsdetector wrote:
               | Seems reasonable that an alien craft travelling between
               | stars might want to illuminate the whole star system to
               | detect dark objects and plot a safe or more perfect
               | course.
               | 
               | Apparently Wow! came from the same area and seemingly was
               | blue-shifted by an amount that could make sense from an
               | approaching craft, so that doesn't sound that silly to
               | me.
               | 
               | Unlikely to be the real cause, not silly.
        
             | ReptileMan wrote:
             | I am open minded, but Arthur Clarke solved it. If it was
             | alien it would have slingshotted around the sun. Unless it
             | is on collision course with a planet or using the sun to
             | modify its course towards another star - you can assume
             | that it is not alien and functioning.
        
               | DennisP wrote:
               | Fwiw, Avi's hypothesis for Oumuamua was not that it was
               | functioning, but that it was old, defunct light sail.
        
             | 827a wrote:
             | Well, you know what they say; don't be so open-minded that
             | your brain falls out.
        
               | keepamovin wrote:
               | Nonsense. Open minded means not precluding possibilities
               | based on irrational bias, which would only increases
               | intelligence.
        
               | 827a wrote:
               | Sure, if the biases are actually irrational, but in this
               | case the biases are things like "idk maybe we should
               | follow the scientific method", while Loeb pushes "here's
               | an idea that is unfalsifiable and untestable, but look
               | its peer reviewed and its on a harvard domain name so you
               | have to pay attention to me".
               | 
               | Loeb is, to be very clear: unintelligent and
               | unscientific. He has no desire to actually test the
               | theories he publishes, and because of that, most of the
               | theories are literally untestable. He just wants to shit-
               | publish wild ideas, which is totally fine, if we were
               | talking about a blog or something of that similar
               | caliber. But that would not attract the $$$ views he
               | demands to afford his lifestyle.
        
             | antonvs wrote:
             | His Galileo Project is explicitly looking for
             | "extraterrestrial technological signatures", and he's just
             | using any opportunity for hype about that.
             | 
             | He got attention for writing about this for Oumuamua, and
             | now he's just rinsing and repeating for 3I/Atlas. It's
             | exactly like any youtuber chasing the most effective
             | clickbait.
             | 
             | It's like when Altman talks about AIs building a Dyson
             | sphere. Everyone with any understanding of the issues knows
             | it's self-serving hype.
        
         | efavdb wrote:
         | Here's an interview of his on this
         | 
         | https://www.youtube.com/watch?v=nf0xB3EtQX0
        
         | Perenti wrote:
         | I had dinner with one of the co-authors Wednesday night. He's
         | doubling down on the "significance" test that has H0 that all
         | possible incoming trajectories are equally likely.
         | 
         | He's convinced it's an essentially a local phenomenon. I look
         | forward to how he spins this paper.
        
       | dostick wrote:
       | > 3I/ATLAS is thought to have been drifting through interstellar
       | space for many billions of years before encountering our solar
       | system.
       | 
       | It is hard to believe, but it means it's been a fiery comet for
       | billions of years, how is that possible that it havent burned
       | up...
        
         | blacksmith_tb wrote:
         | Well nothing much in hard vacuum is "fiery" - comets in our
         | solar system do get ablated by the solar wind as they orbit the
         | sun more closely; I assume in this case the majority of those
         | billions of years were in deep space where there wasn't much
         | pushing/pulling mass off.
        
           | motoboi wrote:
           | Yeah but then it wouldn't be drifting would it?
           | 
           | Joke explanation: a drifting vehicle is burning tires and
           | leaving a cloud of smoke behind, like a comet.
        
             | grues-dinner wrote:
             | Whether it's drifting through space or hammering through at
             | dozens of kilometres a second is rather a matter of
             | perspective. Perhaps as far as it's concerned, its sedate
             | drift has been interrupted by a very ill-mannered solar
             | system making a reckless close pass.
        
               | lazide wrote:
               | Yes, the solar system is moving (rotating) relative to
               | the galactic core at 230 KM/s, far faster than this
               | object is moving relative to us.
               | 
               | Depending on its origin/history, it's getting run over by
               | a runaway train, or taking a sedate walk.
        
               | mrexroad wrote:
               | Tangentially, I enjoy reminding my kids how long it takes
               | our star to complete a rotation around the Milky Way, and
               | then also point out that we can go to a museum and see
               | fossils of what life looked like one galactic rotation
               | ago. It gives the right amount of backward and forward
               | perspective about the rock we live on that I want them to
               | keep tucked away in the corner of their mind.
        
               | wasting_time wrote:
               | This object is "moving" at roughly 58 km/s. It's doing a
               | leisurely Sunday drive and getting overtaken by someone
               | 3x their speed.
        
               | longos wrote:
               | Hopefully our solar system isn't making a reckless pass
               | into the path of the fragments from a historic explosion
               | and we're just seeing the first few.
        
           | codr7 wrote:
           | Wind in a vacuum, that's interesting.
        
         | 8fingerlouie wrote:
         | Because what makes it glow is actually solar wind from our sun
         | as it passes through the solar system.
         | 
         | For possibly billions of years, it has simply been an inert
         | lump of ice passing through the universe.
        
           | TheOtherHobbes wrote:
           | It could be extra-galactic. It's going at a fair clip, and
           | (if I haven't dropped a zero or ten) it would only take
           | around 800 million years to get here from one of the
           | Magellanic Clouds.
           | 
           | Just as an indicator of the speed and possible distances.
        
             | mrexroad wrote:
             | > "But based on the researchers' analyses of the
             | interstellar object's vertical motion in the galaxy (its
             | path is known to weave up and down in the galactic disk),
             | they concluded that it likely originated from the Milky
             | Way's thin disk, not its thick disk as was mentioned some
             | months ago. The thin disk contains somewhat younger objects
             | than the thick disk."
        
         | BirAdam wrote:
         | If it were traveling through interstellar space, it would have
         | been highly irradiated but it would also have been far from any
         | source of heat. From what we know of it so far, it has some
         | strange chemistry going on, but that's somewhat expected given
         | its estimated age. We'd also need to assume that a few billion
         | years of interstellar radiation would do strange things we
         | haven't really seen before hence pointing every instrument
         | possible at it.
        
         | ceejayoz wrote:
         | Comets don't do anything much until they get close to a star.
        
       | TMWNN wrote:
       | I was surprised to recently learn that NASA has aimed pretty much
       | everything it has at 3I/Atlas, even the Perseverance Mars rover!
       | <https://science.nasa.gov/solar-system/comets/3i-atlas/>
        
         | dweekly wrote:
         | Genuinely curious: what could the Mars rover possibly capture
         | about this object that other instruments cannot? Is it our
         | highest resolution imagery in the vicinity of Mars?
        
           | exe34 wrote:
           | my favourite sci-fi idea about this is that the aliens know
           | we love shiny things so they give us a comet to look at while
           | they have their annual picnic somewhere nearby.
        
           | exitb wrote:
           | When you look at images of the comet Siding Spring made from
           | Mars surface and orbit, it's clear that neither of the
           | instruments are really well suited for that type of
           | observation. In such case, you just use everything you have
           | and hope for the best.
        
           | philbo wrote:
           | Not much, but just confirmation that it's in the expected
           | part of the sky is quite exciting. There's a probable capture
           | of it from Perseverance here (it's just a tiny faint smudge):
           | 
           | https://bsky.app/profile/stim3on.bsky.social/post/3m2aqnbwlw.
           | ..
        
             | Razengan wrote:
             | > _just confirmation that it 's in the expected part of the
             | sky is quite exciting_
             | 
             | It would be funny if it behaves "as expected" when in the
             | range of our instruments, but not when it thinks we can't
             | see it :)
        
               | philbo wrote:
               | Every confirmation is a data point.
        
           | pengaru wrote:
           | I supposed that depends on if the object deploys a probe to
           | go take a selfie with the rover? Would be a damn shame to
           | miss capturing evidence of it up close and personal...
        
       | Marsk wrote:
       | https://science.nasa.gov/solar-system/comets/3i-atlas/
       | interesting blurb at the top of the site... "Due to the lapse in
       | federal government funding, NASA is not updating this website."
        
         | preisschild wrote:
         | at least it's not saying "thanks to the radical left democrats"
         | like other govt websites
        
           | CamperBob2 wrote:
           | Looks like you were downvoted by someone who either thought
           | you were kidding, thought you were posting false partisan
           | flamebait, or thinks that the language used by the Trump
           | administration is just peachy keen. Regardless, they were
           | wrong.
           | 
           | https://abc7.com/post/government-websites-displaying-
           | message...
        
             | svachalek wrote:
             | https://www.hud.gov/
        
               | CamperBob2 wrote:
               | Good lord. That's worse than I'd heard.
               | 
               | We're pretty much hosed.
        
           | reaperducer wrote:
           | Some departments have even added similar language to
           | employees' e-mail out-of-office messages.
        
             | mystraline wrote:
             | Thats correct. Some groups have. More groups refuse to
             | break the Hatch Act and take partisan sides.
             | 
             | Theres a LOT of people who work for the government that
             | want to do a good job, and faithfully keep doing what
             | they're paid to do. Administrations dont matter. The
             | mission does. And that mission goes year by year.
             | 
             | Well, until now.
        
               | antonvs wrote:
               | > Theres a LOT of people who work for the government that
               | want to do a good job, and faithfully keep doing what
               | they're paid to do.
               | 
               | And the current administration calls those people "the
               | deep state" and wants to get rid of them.
        
           | downrightmike wrote:
           | So far left, they are actually far right
        
       | dnw wrote:
       | Have we gotten better at detecting these objects in the past 5
       | years or is the solar system going through a bumpy area of Milky
       | Way lately? We have observed (or I have heard about) many
       | interstellar objects in the past five years than any previous
       | times.
        
         | bravoetch wrote:
         | From wikipedia: "As of 2025, three interstellar objects have
         | been discovered traveling through the Solar System:
         | 1I/`Oumuamua in 2017, 2I/Borisov in 2019, and 3I/ATLAS in 2025"
         | 
         | I would guess that observation improves over time. The
         | wikipedia article is fascinating, estimating 10,000 such
         | objects passing within Neptune's orbit in our solar system each
         | day. I think that includes dust and sand sized objects.
        
         | eugenekay wrote:
         | Computing Power has increased tremendously, along with the
         | higher resolution of digital imaging technology compared to
         | analog film plates. Sky Survey projects like the Vera C. Rubin
         | Observatory have become active in recent years, which generate
         | Terabytes of spectrographic data each night which can be
         | rapidly examined for differences from previous captures. In the
         | past each exposure had to be hand-aligned on a Light table and
         | "flipped" between to spot differences.
        
         | throwup238 wrote:
         | There has been a significant increase in NEO observation
         | projects in the last eight years and there's one coming online
         | soon that should increase the detection capabilities even more.
         | 
         | Pan-STARRS (discovered 1I/`Oumuamua), Zwicky Transient Facility
         | (2I/Borisov), and ATLAS (3I/ATLAS) are the major existing
         | projects and the Rubin Observatory/LSST will be a huge upgrade.
         | We're going to detect a lot more if these objects, especially
         | since a lot of the work of the projects are looking at
         | historical data.
        
           | coolspot wrote:
           | 2I/Borisov was not discovered by Zwicky Transient Facility .
           | 
           | The comet was discovered on 30 August 2019 by amateur
           | astronomer Gennadiy Borisov at his personal observatory MARGO
           | in Nauchnij, Crimea, using a 0.65 meter telescope he designed
           | and built himself.
        
             | zeven7 wrote:
             | That's interesting. If it was possible to do on a homemade
             | telescope, then why were no interstellar objects discovered
             | before 1A?
        
               | MalbertKerman wrote:
               | The hard part isn't having a telescope, but analyzing the
               | images for objects that have moved between successive
               | observations. Digital astrophotography and analysis
               | software have been getting steadily cheaper and better,
               | which leads to more amateur comet hunters each watching
               | more sky, which has rapidly improved the odds of catching
               | rare objects.
               | 
               | I'm not sure how the progress of institutional and
               | amateur observations compare. Obviously the big guys
               | benefit from the same technological advancement, but I
               | don't know whether the fraction of new objects discovered
               | by amateurs has been growing or not. I suspect the odds
               | of the first interstellar object being found by an
               | amateur were still pretty long.
        
         | dreamcompiler wrote:
         | It's detection, not a particularly crowded area of space. These
         | rocks are hard to see, and one needs at least 3 observations
         | (in theory, but in practice more) to compute their path and
         | determine that they're extrasolar. Within 5 years we'll
         | probably be detecting several of them a week.
        
           | dhosek wrote:
           | It's worth noting that we went from wondering if other stars
           | had planets to hitting 6000 detected so far in about four
           | decades with just 33 years since the first discovery of an
           | exoplanet (and 30 years since one was found orbiting a main-
           | sequence star--that first was actually two planets which
           | orbited a neutron star).
        
             | SiempreViernes wrote:
             | A funny overview of the recent history
             | https://www.youtube.com/watch?v=gai8dMA19Sw
        
               | dreamcompiler wrote:
               | Somewhere in the galaxy, silicon-based lifeforms who
               | enjoy swimming in molten lead have trained their
               | telescopes on our solar system and mapped it. They have
               | assumed all the planets here are incapable of supporting
               | life, except for the second one: It's right in their
               | habitable zone. Their ships are speeding toward Venus as
               | we speak.
        
               | alganet wrote:
               | If _some_ kind of life is possible in Venus, shouldn't
               | Venus have it?
               | 
               | That's how life works on Earth. If it _can_ live
               | somewhere, it's probably already there. We think that's
               | related to how it can survive and adapt, so it's
               | reasonable to assume other life would be similar in that
               | regard.
               | 
               | Therefore, by this logic, if Venus is able to sustain any
               | life, it should already be there.
               | 
               | I know it sounds weird. What if life never got there?
               | Well, it had plenty of opportunity. The universe is old
               | and lots of things happened in it already.
               | 
               | Maybe life is a late addition to the universe, and we're
               | one of the first instances of it. Or maybe it's rare, and
               | we're lucky. Both the "life is new" and "life is rare"
               | ideas, however, paint a picture of Earth being a special
               | case somehow. "We are a special case" is not a very
               | satisfying answer though (from the scientific point of
               | view).
        
               | dreamcompiler wrote:
               | > Therefore, by this logic, if Venus is able to sustain
               | any life, it should already be there.
               | 
               | How do you know it's not? Venus is a much more difficult
               | place for us to analyze than say, Mars.
        
               | alganet wrote:
               | Maybe it is, I don't know.
               | 
               | I was talking about your scenario of space-faring
               | silicon-based life. If Venus can support this different
               | life, then it should be already there.
               | 
               | It's hard enough to find signs of life similar to ours
               | (something familiar, carbon, metabolism), so if there is
               | some completely different life somewhere in the solar
               | system, it's unlikely we would be able to recognize it at
               | first glance. So unlikely, that is almost pointless to
               | postulate its existence.
               | 
               | Therefore, our best shot is to look for life similar to
               | ours (because we know its tells). I think that's where
               | the idea of a habitability zone comes from. It's not
               | excluding the possibility of life existing outside of the
               | zone, it's just making it easier for us to look (because
               | looking everywhere means considering things we can't
               | possibly understand).
               | 
               | That idea has been slightly changed since we started to
               | hypothesize life on moons like Europa and Enceladus
               | though. They are outside the classical habitable zone,
               | but they have other possible means for producing liquid
               | water that don't rely on the heat of a close star (tidal
               | friction and residual core heat).
        
         | cheschire wrote:
         | 5 years ago space got a whole force dedicated to it in the US.
         | Perhaps this is the result of an increase in military research
         | efforts? The timing is an interesting coincidence if anything.
        
           | zeven7 wrote:
           | We know exactly who discovered these objects, what tech they
           | were using, and where the funding came from, and it wasn't
           | from space force.
        
             | cheschire wrote:
             | "we" does not include me, which is why I posed it as a
             | question, and made the allowance that it's at least an
             | interesting coincidence to me.
             | 
             | I'm not sure why that warrants a flood of downvotes,
             | especially increasing after your message called me out, but
             | hey I guess that's HN now.
        
               | quuxplusone wrote:
               | FWIW, HN values directness and precision, even in
               | questions. I bet if you'd said "Did increased military
               | spending have anything to do with this?" you'd get a
               | quick answer "no" and few downvotes; but what you
               | _actually_ said was  "Perhaps this is the result of an
               | increase in military research efforts" with a question
               | mark on the end, and I expect HN was reacting to that.
        
       | baggy_trough wrote:
       | How likely is it that a random object from outside the solar
       | system would pass so closely by Mars and Jupiter?
        
         | grues-dinner wrote:
         | How likely is it that a random alien object does a wellness
         | check on a barren planet in the same decade the humans happen
         | to turn on the big survey telescope array?
        
           | baggy_trough wrote:
           | Pretty likely if there are a lot of them!
        
             | grues-dinner wrote:
             | Then I guess we'll see another one soon (unless we freak
             | them out by noticing them and broadcasting about it!).
             | 
             | Once more survey telescopes like Nancy Grace Roman and
             | Xuntian come online we'll increasingly find out how many
             | there really are and I suppose if they seem to like buzzing
             | the proverbial tower.
        
               | 827a wrote:
               | In fact, we already have; that's why there's a 3 in its
               | name.
        
               | grues-dinner wrote:
               | The other two didn't make a planetary close pass. As we
               | see more of them, the statistical strangeness of the
               | third one getting so close to Mars will fade. (Or, I
               | suppose, they keep doing it and then we _really_ will
               | have a puzzle on our hands!)
        
           | ceejayoz wrote:
           | Shuffle a deck of cards, and statistically no one has ever
           | shuffled the same sequence in all of human history.
           | 
           | It is extraordinarily unlikely you will shuffle one
           | particular order of cards. It is 100% likely you will result
           | in _a_ sequence of cards.
           | 
           | Space is full of trillions and trillions and trillions of
           | these. Given the rate of detection, we'll probably see them
           | come through regularly.
        
             | grues-dinner wrote:
             | That's my point. If you turn on several telescopes
             | particularly good at seeing these things and see three
             | objects in fairly quick succession, the implication is
             | probably (not certainly) that there are lots of
             | interstellar objects hammering in all the time, not that
             | the first ones you see are particularly special, even if
             | one of them seems to be making a statistically unlikely
             | near approach to Mars.
        
               | ceejayoz wrote:
               | Yeah, like exoplanets. When I was in middle school there
               | were none. Now there's 6,000 confirmed ones.
        
               | onion2k wrote:
               | Surely no one was actually thinking there _weren 't_
               | exoplanets though. We didn't need experimental proof that
               | they exist to be reasonably sure that they do.
        
               | dhosek wrote:
               | The existence of exoplanets was an open question still in
               | the 80s. They were pretty sure that they existed, but no
               | one had any evidence of it. It fell kind of in the same
               | category of whether the Riemann conjecture is true.
               | Mathematicians are pretty sure it is, but they don't know
               | for sure.
        
               | baggy_trough wrote:
               | I'm curious how unlikely it is. Seems very, very unlikely
               | to pass by 2 major planets.
        
               | ceejayoz wrote:
               | It is. It's similarly unlikely that I win the lottery.
               | But someone always does!
        
               | baggy_trough wrote:
               | The situations are in no way analogous.
        
               | ceejayoz wrote:
               | Sure they are. There are likely trillions of these
               | things. We are likely gonna see them everywhere. Like
               | scratch-off lottery cards.
        
               | baggy_trough wrote:
               | We have seen 3.
        
               | PoorlyNamed wrote:
               | Any path it could possibly take is equally unlikely.
        
           | mytailorisrich wrote:
           | Aliens have been doing this every few years for 250,000 years
           | but we've just only managed to build barely decent telescopes
           | ;)
        
         | downrightmike wrote:
         | I wonder if we are going through a debris cloud and these are
         | just the first small objects.
        
           | rkomorn wrote:
           | I find this to be an interesting thought.
        
           | codr7 wrote:
           | This one is anything but small.
        
           | simonh wrote:
           | We have only recently been able to detect them at scale, so
           | we should not confuse first ones detected with first ones to
           | arrive in the solar system. It's just as likely they are the
           | tail end of a debris cloud, but our detection tech wasn't up
           | to spotting all the previous ones.
        
         | pedalpete wrote:
         | I may be super naive here, but are we really defining "close"
         | or is it that the object is close enough that it makes sense to
         | point our objects that are close to Jupiter at the new object?
         | 
         | It is passing between two point in our night sky. I believe
         | from a plane view, if you look at our universe from the
         | perspective of it laying flat, it is my understanding the spin
         | of our universe means that everything ends up within a flat
         | plane, so in a 3 dimensional space, we have a limited Y axis.
         | The other planets are spaced out across the X and Y axis, this
         | is passing between or across two points.
         | 
         | Am I thinking of this right? I know very little about
         | astronomy.
        
           | antonvs wrote:
           | There's no evidence that the universe is spinning. The
           | observable universe is not a flat plane - we see galaxies in
           | all directions and at all distances.
           | 
           | You may be thinking of our galaxy (the Milky Way) or even our
           | solar system, which both rotate and as such are both somewhat
           | flattened (the solar system much more so than the galaxy.)
           | 
           | But what's happening here has little to do with that. If you
           | imagine the closest distance that Earth gets to Mars as a
           | yardstick, 3I/Atlas is about half that yardstick's distance
           | from Mars right now - much closer than Earth ever gets. It's
           | practically in Mars' back yard.
        
             | pedalpete wrote:
             | Thanks for clarifying that. And you're right, I was
             | referring to our solar system, not the universe.
             | 
             | It's in Mars' backyard, but was it, or will it also be in
             | Jupiter's backyard? I couldn't understand that from the
             | original post.
             | 
             | It seemed to me that it was just that our
             | telescopes/cameras near Jupiter would be pointed in that
             | direction.
        
               | lrasinen wrote:
               | It's Juice (Jupiter Icy Moons Explorer) and it's not yet
               | anywhere near Jupiter. Its trajectory has a few slingshot
               | loops around Venus and Earth, and it's just coming off
               | the Venus encounter.
               | 
               | It's about 0.43 AU from the comet at its nearest, whereas
               | Earth will be pretty much on the opposite side of the
               | Sun, making observations difficult from here.
               | 
               | Edit: Earth, Mars and Jupiter are in roughly 120 degrees
               | from each other as seen from the Sun, with the Earth-Sun-
               | Jupiter angle closing up fast and the E-S-M angle growing
               | slightly slower. In about two months the E-S-M angle will
               | be 180.
        
             | jacquesm wrote:
             | > There's no evidence that the universe is spinning.
             | 
             | True, but if it were that would solve some problems in
             | observations:
             | 
             | https://academic.oup.com/mnras/article/538/4/3038/8090496?l
             | o...
        
         | lazide wrote:
         | Any object not doing so is very unlikely to be seen by us.
        
           | baggy_trough wrote:
           | Why so?
        
             | lazide wrote:
             | There is a lot of darkness, and we can only look in so many
             | places. We tend to look along the plane of our elliptic
             | because that is where everything in our solar system is.
             | Looking elsewhere is possible, but increasingly lonely/low
             | odds.
        
               | baggy_trough wrote:
               | I don't know if that applies to the sky surveys.
        
               | lazide wrote:
               | 1) they are new 2) they are still limited in coverage
               | area (https://irsa.ipac.caltech.edu/applications/FinderCh
               | art/docs/...)
        
         | ph4rsikal wrote:
         | zero. It must be the Borg after the time jump.
        
       | giardini wrote:
       | "Oh, my God! That's the intergalactic mail van from Xenorph 44!
       | We won't get any more supplies for another century!888----<(((
       | Gaaah! Nothing to eat but Earthlings...."
       | 
       | - overheard on Avi Loeb's radio telescope, but fortunately mis-
       | translated.
        
       | v3ss0n wrote:
       | And NASA shutdown
        
         | freen wrote:
         | Don't Look Up!
        
       | modzu wrote:
       | the thought of this frozen rock drifting through space for
       | billions of years fills me with existential dread :(
        
         | mrexroad wrote:
         | Quite the opposite for me. I'm fascinated and inspired by the
         | fact that this rock escaped the gravity well of one star and is
         | now visiting another.
        
         | stouset wrote:
         | Wait until you hear what Earth has been up to in that same
         | time.
        
         | komali2 wrote:
         | 80 years (if lucky) is an unfathomably cruel prank and a
         | prison.
        
           | bluerooibos wrote:
           | I'm quite hopeful that anyone under 40 (arbitrary, mostly
           | because I'm in my mid-30s) will get to LEV (longevity escape
           | velocity) - there's a ton of anti-ageing and disease-curing
           | research going on, especially now with the likes of DeepMind
           | and others accelerating said research.
           | 
           | That's assuming you manage to avoid death from microplastics,
           | climate change or AI-related societal collapse, etc.
        
         | jmorenoamor wrote:
         | Astronomy usually has that kind of "Lovecraftian" sense of
         | cosmic insignificance when you put things to sacale. Also,
         | being alone at 3am in the middle of nowhere, cold and kind of
         | sleepy, looking at a gas cloud lightyears away, adds to it. But
         | it is also fascinating.
        
           | exe34 wrote:
           | honestly the times I was on a proper telescope, I was
           | shitting myself making sure I made the most of the time going
           | down my list of targets and not getting something wrong and
           | pointing at the wrong star or getting the wrong setting. that
           | and the daemon that had to be restarted every half an hour or
           | so because it crashed. I did not have the energy or time for
           | philosophy. I guess that's the difference between the phd
           | student and the professor haha!
        
         | AtlasBarfed wrote:
         | Now think about how "lucky" this one is it got to float through
         | a solar system.
        
       | rd07 wrote:
       | It is amazing how in under 100 years, we go from first object in
       | space to controlling several spacecrafts in Mars orbit/surface in
       | order to observe a specific object in the sky.
        
       | wbl wrote:
       | Why don't we have an interceptor ready to go for the next one?
        
         | EvgeniyZh wrote:
         | Trip to Mars (~its closest point) is much longer than time we
         | had. The chances the next one will be close enough to Earth and
         | low enough speed so it can be matched is astronomically low and
         | such interceptor would be quite expensive
        
           | wbl wrote:
           | A flyby is fine, and I'm willing to explore some 1960's
           | propulsion solutions.
        
       | librasteve wrote:
       | > it's traveling through our solar system at roughly 130,000
       | miles per hour (210,000 kph). That's the highest velocity ever
       | recorded for a solar system visitor.
       | 
       | so that's the fastest (macro & reachable) thing ever - good luck
       | sticking a flag on it
        
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