[HN Gopher] The Uncensored Guide to 'Oumuamua, Aliens, and That ...
       ___________________________________________________________________
        
       The Uncensored Guide to 'Oumuamua, Aliens, and That Harvard
       Astronomer
        
       Author : mellosouls
       Score  : 77 points
       Date   : 2021-01-29 12:53 UTC (10 hours ago)
        
 (HTM) web link (www.forbes.com)
 (TXT) w3m dump (www.forbes.com)
        
       | annoyingnoob wrote:
       | How do we jump to the conclusion of aliens with so little
       | information? Why not God sent it?
        
         | saberdancer wrote:
         | Oumuamua changed velocity in an unexplained way. This was not
         | expected, but there is an explanation that the object is
         | outgassing and it increases it's velocity.
         | 
         | This, along with strange shape made the object interesting for
         | ET speculation.
        
         | asidiali wrote:
         | If it comes flying in on an asteroid sized spaceship...what's
         | the difference?
        
           | annoyingnoob wrote:
           | I suppose that we could imagine any kind of nonsense. We call
           | that fiction not science.
        
           | nix23 wrote:
           | Spaceship or Gods poo makes a difference i think ;)
        
           | dysfunction wrote:
           | "Asteroid-sized" in this case isn't all that big- 100m long
           | is a similar size to the ISS, though it probably masses a lot
           | more.
        
         | criddell wrote:
         | Nobody has really jumped to that conclusion. I don't think the
         | author of this article has represented Loeb's views or public
         | statements entirely fairly.
         | 
         | Sean Carroll recently interviewed him and if you listen to
         | that, I think you will come away with a very different idea of
         | who Loeb is and what he is saying.
        
       | wsay wrote:
       | I think the inadequate data is the key point, especially as we've
       | only seen two of these types of things so far - the best we can
       | probably hope for now is to go "This object seemed odd in several
       | ways - let's increase our observations for these kinds of objects
       | and see what the majority turn out to be and importantly if we
       | encounter anything which is odd in similar ways which we can
       | identify".
       | 
       | So when the question is posed "What is a responsible scientist to
       | do in this situation?" I think the answer is clearly, accept it
       | as an "out-there" but currently not disprovable hypothesis, and
       | if you feel strongly that it's incorrect, dedicate effort and
       | time to showing with evidence (at least quantifiable empirical
       | evidence) that this is the case, ideally in a published and peer-
       | reviewed paper.
        
       | Tepix wrote:
       | I find the the unnecessary use of "uncensored" to be offending.
        
         | nix23 wrote:
         | It looks like forbes needs to label it like that, bloomberg
         | probably calls it premium account ;)
        
       | voldacar wrote:
       | The last two paragraphs are so incredibly lame. The goal of a
       | scientist's life isn't to be "respected by the community."
       | Science and reality don't care what the community thinks and
       | never have.
       | 
       | I have no idea if Loeb is right or not. I think for Bayesian
       | reasons (prior is Borisov) he is probably wrong, but there is so
       | little data and Oumuamua is certainly super weird. But this
       | author is a total hack, making arguments from authority and
       | mainstream-ness. If a scientist stops making relevant arguments
       | and instead starts talking about the "consensus" of the
       | "scientific community", run the opposite direction
        
       | ckozlowski wrote:
       | I'd gotten the impression that Loeb isn't trying to convince the
       | public and scientific community that it was an alien probe so
       | much as is he trying to show it could have been.
       | 
       | I think is agenda is to get the community looking for these
       | things more often, perhaps out of some disappointment that if it
       | had been an actual probe (a la "Rendezvous with Rama"), we'd
       | already have missed it.
       | 
       | Whether it's worth bending the science to fit this narrative is
       | of course, questionable.
        
         | hh3k0 wrote:
         | > I'd gotten the impression that Loeb isn't trying to convince
         | the public and scientific community that it was an alien probe
         | so much as is he trying to show it could have been.
         | 
         | That was also my impression. A lot of scientists (rightfully)
         | make fun of the dogmatic view that it must have been an alien
         | probe, but fail to realize their view -- that it must have been
         | _anything but_ an alien probe -- is just as dogmatic.
        
         | sandworm101 wrote:
         | His battle is only partly about Oumuamua. That is just a
         | vehicle for his arguments. The real issue is the bias against
         | life detection experiments generally. Want to sample soil on
         | mars and measure oxygen absorption? Great. We will put your
         | sensor on the next rover. Want to pour nutrients on that soil
         | and see if anything eats it? Go away you crazy person. Want to
         | detect methane in an exoplanet atmosphere? Here is your
         | telescope time. Want to detect CFCs, a likely technosignature?
         | Good luck getting them to return your emails. That bias against
         | definitive binary life detection efforts, solid yes/no answers,
         | underpins Loeb's points on Oumuamua. If we are serious about
         | life detection we should be looking for indisputable artifacts
         | of both primitive and complex life, the later of which includes
         | technological life.
         | 
         | Loeb must also fight against widespread public assumptions
         | about the hunt for life, specifically that people think SETI is
         | a giant organization always scanning the sky. The public thinks
         | the scientific community is actually putting in a solid effort
         | to look for aliens. They aren't. We as a society spend more on
         | candycrush than the entire SETI project. Want a definitive
         | answer on whether the next Oumuamua is a light sail? Cough up
         | the money so the scientists can buy the telescope time.
        
           | shmageggy wrote:
           | You're putting a lot of words in his mouth. He did an AMA on
           | reddit yesterday where he had every chance to say such things
           | if that's what he thinks, but he did little more than list
           | his accomplishments and link to his books and articles.
           | 
           | https://old.reddit.com/r/askscience/comments/l6xl3d/askscien.
           | ..
        
             | cambalache wrote:
             | Or you just has not listened to his conversations with Lex
             | Fridman, Sean Carroll and Joe Rogan among others.
        
             | sandworm101 wrote:
             | Note that I said "his battle" rather than "his words". He
             | is but one voice in the fight against the particular
             | scientific bias I described. Had Oumuamua not come along,
             | he would have attached to any number of other vehicles (eg
             | BLC-1) to make basically the same points.
        
           | giantrobot wrote:
           | Science money is _very_ limited. Space science money more
           | limited. Space science money to get components on rovers yet
           | more limited. Telescope time is also limited. Mission time on
           | remote probes is also limited.
           | 
           | So you devise an experiment to measure oxygen absorption that
           | uses a probe's existing mass spectrometer. Your experiment
           | doesn't cut into the probe's mass budget so it basically is
           | just a scheduling issue. If your experiment is bumped from
           | the mission schedule there's not compromising the probe or
           | total mission. You've got a pretty good chance of getting
           | that experiment on the docket.
           | 
           | This is contrary to a nutrient experiment that eats into the
           | probe's mass budget and mission time. If the sensors are
           | dedicated to the experiment that's less mass for other
           | sensors. Even if you got approved if you can't built the
           | experiment to be reliable and survivable it won't get
           | approved.
           | 
           | Similar is true for trying to measure CFCs on exoplanets.
           | There's a handful of instruments that can even get spectra
           | from exoplanets and even then only from transiting ones and
           | _even then_ only has giants so far. Even if we could detect
           | CFCs in terrestrial planet atmospheres, CFCs do not stay in
           | the atmosphere very long so you 'd only detect them (from a
           | technological civilization) for a very short window of time.
           | The odds of finding them are vanishingly low with current
           | instruments. No one is going to return your e-mails if you
           | propose observations of CFCs because it's a snipe hunt
           | wasting valuable and limited instrument time. If you're a
           | serious researcher you'd know this already and wouldn't waste
           | people's time. Methane is a general purpose biomarker and is
           | something far more likely to be found. Since you've got a
           | limited stars you can even gather information from the time
           | is better spent on the more likely observation.
        
             | krok wrote:
             | I mean, you're just reciting the arguments that the science
             | establishment generally recites.
             | 
             | We have spent tons of money on particle accelerators to no
             | clear benefit, either to science or to society. If a
             | similar amount of money had gone to SETI, many of the above
             | objections would have been addressed and resolved, with the
             | advantage that science is being done which the average
             | person paying for it is likely to a) understand what is
             | being asked and b) be interested in the answer.
        
               | giantrobot wrote:
               | I did pull my arguments out of the "Big Astronomy: Let's
               | Keep Down The Little Guys" playbook. Come off it. The
               | "science establishment" repeats things because there's
               | compelling evidence and scientific rigor supporting those
               | things. It's not some "Big Science" conspiracy.
               | 
               | Particle accelerators have exploratory experiments like
               | hunting the Higgs boson with LHC but they run lots of
               | other experiments as well. There's also lots of particle
               | accelerators (of varying capability) around so if you
               | devise an experiment needing one you likely have several
               | options unless you literally need the LHC.
               | 
               | With large telescopes there's far fewer available and the
               | sky is pretty big. Radio SETI is a long shot search and
               | optical SETI even more so. It's not that they lack merit
               | but getting funding for telescope time is a lot harder
               | when the chance of any positive finding is very remote. A
               | lot of SETI funding actually piggybacks on other research
               | using the same telescopes.
               | 
               | The chances of SETI finding positive results isn't
               | necessarily from a lack of things to find but from
               | physical limitations. Our _best_ radio telescopes could
               | only detect Earth 's more powerful radio emissions from a
               | few light years away. Broadcasts like TV and radio
               | wouldn't be detectable outside the solar system. The
               | inverse square law is a stone cold bitch for interstellar
               | communication. SETI's best hope of finding signals are
               | ones intentional ones.
               | 
               | Even with billions of dollars SETI would have similar
               | chances of detecting an ETI as without. It's a needle in
               | a haystack search with warehouse sized haystacks. More
               | money doesn't necessarily get it done much faster or
               | better. There's a limited number of sites for large radio
               | telescopes and they have limited fields of view and stars
               | are only in that FOV for a limited time. More money might
               | let you search the warehouse sized haystack a few times
               | faster but it's still a vast search space.
        
             | sandworm101 wrote:
             | >> if you propose observations of CFCs because it's a snipe
             | hunt wasting valuable and limited instrument time.
             | 
             | That's what they said about hot jupiters. Exoplanets could
             | have been detected _decades_ earlier had there not been a
             | consistent bias against the idea of large objects orbiting
             | so near host stars, a bias based on a single data point
             | (our solar system).
        
               | giantrobot wrote:
               | It's unlikely many types of exoplanets could have been
               | detected "decades" earlier. Transit and Doppler detection
               | methods require good seeing power and accurate intensity
               | measurements. It takes large mirrors with good optics for
               | good seeing power and sensitive electronics for the
               | spectral/intensity measurements. Those two things weren't
               | readily available until the past few decades...which
               | surprise is when exoplanet discoveries started happening.
               | 
               | Hot Jupiters and CFCs are very different things. Hot
               | Jupiters were puzzling but something that _could_ be
               | readily detected by existing instruments. Once discovered
               | solar system development models were improved.
               | 
               | CFCs in a planet's atmosphere is something current
               | instruments _can 't_ detect. Even if they could the
               | number of observational candidates is limited. The only
               | way we could detect CFCs is if some civilization was
               | actively producing them at the time that light left the
               | planet. So even if there's millions of CFC producing
               | civilizations in the galaxy the odds of detecting those
               | CFCs in candidate systems is extremely low. Even if those
               | civilizations produced CFCs for millennia the odds are
               | against ever seeing them. So it's pretty wasteful to use
               | valuable telescope time for that rather than something
               | that has a higher probability of giving some results.
               | 
               | It's not about solar system chauvinism or biases. There's
               | not infinite amounts of science money or science time. No
               | one is writing off unlikely events, it's just breathless
               | searches for those unlikely events has a huge opportunity
               | cost. And talking about biases, assuming technological
               | civilizations will produce CFCs is a very Earth/Human
               | biased assumption. CFCs were/are produced on Earth for
               | market reasons that don't necessarily apply in any
               | circumstances except those that worked out on Earth.
        
               | sandworm101 wrote:
               | >> It's unlikely many types of exoplanets
               | 
               | Ya, but if people were allowed to look for hot jupiters
               | in the 70s/80s they would have found the _first_
               | exoplanet far sooner.
        
               | giantrobot wrote:
               | Allowed? No one was banned from looking for Hot Jupiters.
               | They weren't an expected phenomenon. The instruments to
               | detect them also didn't/barely exist in the 70s and 80s
               | and they're some of the _easiest_ exoplanets to detect.
        
           | Spooky23 wrote:
           | It's a political problem because basic research on these
           | matters still requires money that mostly comes from the US
           | government.
           | 
           | Space stuff exists because it's a jobs program in the South.
           | The search for life starts crossing lines because it raises
           | awkward questions that challenge politically meaningful
           | people.
           | 
           | End of the day, you don't bite the hand that feeds.
        
           | api wrote:
           | At least one Mars lander has discovered ice and evidence of
           | briny water beneath the soil. The fact that we have not sent
           | a microscope just baffles me.
           | 
           | I do get the sense that for whatever reason there is a bias
           | against explicitly looking for life. I don't think there's a
           | big conspiracy explanation. I personally think it's what I
           | call the "boring universe brigade," the skeptic ideology that
           | came to dominate science starting in the 1970s that treats
           | fascination as a contrarian indicator. "If it really
           | fascinates people it's probably bullshit."
           | 
           | If there's anything beyond that bias it's probably a fear of
           | triggering fundamentalists.
           | 
           | Edit:
           | 
           | Here's one bit of evidence for possible near surface water at
           | a landing site:
           | 
           | https://www.space.com/209-life-mars-scientist-claims.html
        
           | DiogenesKynikos wrote:
           | Astronomers are extremely interested in detecting
           | biosognatures in exoplanet atmospheres. This is one of the
           | hottest topics in astronomy right now. They're just not
           | interested in idle speculation about whether or not Oumuamua
           | is a light sail. If there were some measurement that could be
           | done to learn more about Oumuamua, then astronomers would do
           | it, but it's a tiny object that's quite far away now. Most
           | astronomers simply believe that the most likely explanation
           | for the anomalous acceleration is that there was some
           | undetected outgassing from the rock. That's much more
           | plausible than the idea that _this one particular object_ is
           | an alien spaceship - not because there couldn 't be alien
           | spaceships somewhere out there, but because there are so many
           | rocks floating around in space.
           | 
           | The one thing that you really can't get funding for is SETI,
           | but that's not the fault of astronomers. That's the fault of
           | congresspeople who ridiculed the search for "little green
           | men" in the 1990s and barred NASA from funding it. Almost all
           | astronomy funding comes from governments, so a government ban
           | on funding a particular line of research means that that
           | research basically won't happen.
        
       | gamapuna wrote:
       | Here's a recent interview of Avi Loeb on this subject
       | https://www.youtube.com/watch?v=_DQYiyQ7Tkk
        
         | nabla9 wrote:
         | That is probably the best interview/podcast made with Avi Loeb.
         | 
         | Mindscape podcast (Sean Carroll) is really good.
        
       | Vrondi wrote:
       | Dr. Loeb was just a guest on the NPR show "Science Friday" last
       | week, explaining that Science has an obligation to explore these
       | questions instead of dogmatically refusing to explore the
       | possibilities. Interesting listen:
       | 
       | https://www.sciencefriday.com/episodes/january-22-2021/
        
       | [deleted]
        
       | eightails wrote:
       | How hard is it for people to just admit that we probably have
       | inadequate evidence to reach a solid conclusion. This was the
       | first object of its kind and we had very limited observations of
       | it. From what I've read, none of the hypotheses regarding the
       | measured acceleration (e.g. outgassing vs manufactured solar
       | sail) can really be backed up in any substantial way. So it seems
       | disengenuous to get into vitriolic arguments about it.
       | 
       | We just have to keep watching, more thoroughly and with better
       | equipment.
        
         | jcims wrote:
         | I think some of the vitriol comes around the discussion of
         | whether or not we should develop a mission to go visit it.
        
           | ericbarrett wrote:
           | There's no chance of catching Oumuamua. It's leaving the
           | solar system at 26 km/s and it has a 3 year head start.
        
             | jcims wrote:
             | Today no. It's clearly possible but it's probably a 50 year
             | objective between technology development and mission
             | operations.
        
               | cambalache wrote:
               | Good luck finding a 200-m object at 273 AU.
        
             | garmaine wrote:
             | There are mission profiles that could manage a flyby on a
             | multi-decade timeline.
        
           | postalrat wrote:
           | The conspiracy theorist in my wants to believe that if the
           | military thought it could be from an alien civilization they
           | already have a mission to reach it and would do what they can
           | to prevent any sort of public mission from reaching it.
        
             | jamesdmiller wrote:
             | By this logic, the military would have started vaccinating
             | their troops for COVID by March 2020.
        
               | postalrat wrote:
               | How is that in any way related?
        
               | yoz-y wrote:
               | Both imply that the military has scientific knowledge
               | that the bulk of public research does not. (about events
               | that are not directly caused by them)
        
               | gdubs wrote:
               | It's pretty well documented that intelligence agencies
               | new about the novel coronavirus very early on, and we
               | know the vaccines were completed very rapidly after the
               | genomic information was published -- so this argument is
               | sort of off. The US appears to have had reasons for not
               | rushing to vaccinate its military. China, by contrast,
               | made the decision to vaccinate their troops a lot
               | earlier.
               | 
               | In other words the military clearly _does_ have early
               | eyes on all sorts of situations - and their action or
               | inaction on that info is a separate consideration.
        
           | Tuna-Fish wrote:
           | That's simply not practically possible. It's just going too
           | fast. We would either have to build a really stupendously big
           | rocket, or develop propulsion that is dramatically more
           | efficient than anything ever done before.
        
             | jcims wrote:
             | That's the point. If we received some kind of undeniable
             | evidence that it was alien technology we would have three
             | parallel 'Contact' level operations underway to go get it.
             | 
             | As a mystery object we might finally get someone to develop
             | a mission based on a science objective once some of the
             | technology has been sufficiently developed.
        
             | garmaine wrote:
             | Or launch a cubesat on top of a Falcon Heavy with a Vulcan
             | Centaur kick stage and a Jupiter gravity assist.
        
           | s1artibartfast wrote:
           | I haven't seen anyone in the scientific community actually
           | push for this. I'm not sure it is even what Avi Loeb is
           | pushing for.
        
         | erdos4d wrote:
         | That the object could have outgassed 10% of its mass while
         | exiting the solar system and produced a steady acceleration
         | with no detectable change to its orbital period stretches all
         | believability. However, I've seen similar bullshit pass as
         | explaining such cases consistently in this field, and if anyone
         | doubts it or makes an issue about it for too long, they get the
         | old peer pressure applied to get them in line, or end their
         | career. I think that is part of where the vitrol comes from.
         | People don't like being silenced or losing their respectability
         | because someone waved their hands a lot and said they explained
         | something.
        
         | postalrat wrote:
         | Of course we need to keep watching.
         | 
         | But at the same time why shouldn't we continue trying to
         | understand what oumuamua is based on everything we know?
        
           | sandworm101 wrote:
           | >> to understand what oumuamua is based on everything we
           | know?
           | 
           | Sure, but one should not make big decisions on so few data
           | points. The data shows it as accelerating. Ok. I'm still not
           | willing to say "alien civilizations exist and are using light
           | sails" based on a handful of observations of a single object.
           | One should hold off such monumental determinations until one
           | has profound data available. So once any discussion moves
           | from "it was accelerating" to "aliens are real", many serious
           | scientists will just walk away. They will come back once
           | there is a more appropriate data set for such discussions.
        
           | duxup wrote:
           | I don't think your statement and the person you responded to
           | necessarily conflict.
        
         | Gys wrote:
         | Early mankind did not understand storms and thunder and
         | invented gods to explain the phenomenon. We still have
         | phenomenon we cannot explain but ruled out gods. So now
         | alternatively we like extraterrestrial life for explanations :)
        
           | karmakaze wrote:
           | I don't think it's quite the same. We know there are things
           | we don't know from continuous discoveries of things we didn't
           | know before.
           | 
           | From my perspective I want aliens to exist, if for no other
           | reason than to resolve the Fermi paradox: one less unknown.
           | Existence if true is easier to prove than non-existence if
           | true.
        
         | andrewflnr wrote:
         | > How hard is it for people to just admit that we probably have
         | inadequate evidence to reach a solid conclusion.
         | 
         | Evidence indicates: extremely hard. People are extremely
         | uncomfortable with ambiguity and uncertainty. In a variety of
         | circumstances, ranging from the storms another commenter
         | mentioned to your favorite political issue, people will happily
         | make stuff up and believe it rather than accept uncertainty.
         | From a certain perspective it's hard to fault this instinct,
         | since true certainty is almost never possible but we still have
         | to make decisions in finite timeframes. If you're careful, you
         | can probably catch yourself doing the same thing.
        
         | BobbyJo wrote:
         | Well, no, the arguments are still important whether or not we
         | can reach a definitive conclusion, because they inform what
         | "keep watching" means. If there is a stronger consensus that
         | it's an outgassing comet, then money/time/resources will be
         | invested in looking for evidence of that. Likewise, of the
         | consensus is that it's a probe, those same resources will be
         | invested differently.
         | 
         | This is actually Avi's argument for considering the probe
         | hypothesis. He's not trying to prove it was a probe, he's
         | making a case for investing resources into experiments that
         | could detect probes and industrialized alien civilizations, as
         | opposed to detecting new classes of comets.
        
         | calibas wrote:
         | I think it's precisely because we don't know that people have
         | such strong opinions. People get to fill in what they want to
         | believe, then argue a point that can never really be proven
         | wrong or right.
        
           | bostonsre wrote:
           | Yea.. saying "I don't know" is extremely powerful and
           | important but it doesn't seem to be said enough.
        
         | TheOtherHobbes wrote:
         | The reason we have inadequate evidence is the relatively low
         | priority of SETI compared to other science.
         | 
         | SETI has literally been living off financial scraps for
         | decades. If a couple of billionaires hadn't funded efforts with
         | very generous personal donations there would be almost no SETI
         | at all.
         | 
         | And if SETI had been funded properly - which would still be a
         | drop in the ocean compared to other government spending,
         | nationally and internationally - we'd have more observations to
         | draw on from other sources.
         | 
         | This is all quite strange considering how much of a game
         | changer and scientific motivator evidence of ETI would be.
        
           | BatFastard wrote:
           | It could be that the government knows ETs exist, so it is
           | pretty much of a moot point to spend money on searching for
           | them.
        
             | PopsiclePete wrote:
             | Twenty years ago, I'd have been more willing to agree with
             | that. I could see the US Gov't as some sort of sinister,
             | hyper-competent (and even malevolent?) force that could
             | definitely keep a secret like that forever from us, and
             | "disappear" those that get too nosy.
             | 
             | Now? Not so much. Looking at who our "representatives" are
             | - failed football coaches, regular conspiracy nuts -
             | there's no way in hell that this "knowledge" would remain
             | locked away for years, decades. Not with clowns like these
             | in charge.
        
           | ComputerGuru wrote:
           | > This is all quite strange considering how much of a game
           | changer and scientific motivator evidence of ETI would be.
           | 
           | All conspiracy theories aside, there is an argument to be
           | made that something with the potential to completely undo the
           | status quo would, in a less-than-ideal world, have a hard
           | time finding funding from those at the top of the totem pole
           | of power.
        
           | TheBlight wrote:
           | >This is all quite strange considering how much of a game
           | changer and scientific motivator evidence of ETI would be.
           | 
           | Well not only a motivator in an inspirational sense but if we
           | can actually get our hands on ET debris who knows what
           | technical leaps we might achieve by attempting to reverse
           | engineer it/parts of it.
        
       | [deleted]
        
       | Itinerant662 wrote:
       | Contrary to the narratives you'll find elsewhere, including in
       | Loeb's new book, Extraterrestrial: The First Sign of Life Beyond
       | Earth, this is not a possibility worth taking seriously as a
       | scientist. A straightforward look at the evidence shows us why."
       | -> "Loeb offers only loud, immodest speculation about aliens and
       | diatribes about community groupthink. Coupled with inadequate
       | data, which is the only data we have, he's impossible to prove
       | wrong."
        
         | krok wrote:
         | If something is impossible to prove wrong _because of
         | inadequate data_ isn 't that a strong suggestion that further
         | research would be a good idea??
        
       | willis936 wrote:
       | Oumuamua raises some questions, but the one my mind keeps
       | wandering to is "how common are these interstellar objects?"
       | 
       | It poses a serious existential threat to us. We are a tiny
       | target, but we have been able to observe these objects for a very
       | short period of time. Unlike regular solar satellites, they are
       | only visible for a very short period of time. Like comets, if one
       | hit us it would end life on the planet. They don't need to be
       | massive with how fast they are. We can estimate how many comets
       | are out there with orbital mechanics models, but what about
       | objects originating from outside the solar system? We could one
       | day not wake up because we couldn't even see one of these coming
       | before it hit us.
        
         | detritus wrote:
         | > Like comets, if one hit us it would end life on the planet.
         | 
         | 'Oumuamua is more of a 'city-killer' risk at its size than a
         | comet such as Halley's, which would be more of the sort of
         | range of size that could seriously screw up our day.
        
           | willis936 wrote:
           | True, Oumuamua itself would not have done Earth changing
           | damage even in the worst case collision, but where there is
           | one we have to ask "are there others?" and "how big are
           | they?"
           | 
           | We have a pretty good idea of the asteroids and comets in
           | stable orbits around the sun. We know with certainty we're
           | not going to be hit with a planet killer asteroid in the next
           | hundred years because we track all of them.
        
             | AnimalMuppet wrote:
             | We track _all of them that we know of_. And we _think_ that
             | we know most of them. I 'm not sure that we know all of
             | them; I'm not sure that the trackers think that, either.
        
               | willis936 wrote:
               | Actually, we do. Asteroids large enough to be considered
               | planet-killers are the easiest ones to spot.
               | 
               | https://youtu.be/4Wrc4fHSCpw
        
         | avian wrote:
         | > We can estimate how many comets are out there with orbital
         | mechanics models, but what about objects originating from
         | outside the solar system?
         | 
         | We can estimate the frequency and size of impacts, regardless
         | of the origin of the impacting body, from observing craters on
         | the Earth, moon and other planets. Those show that the "end of
         | life" impacts are pretty rare - the conclusion that also
         | follows from the fact that we're having this discussion here.
        
           | willis936 wrote:
           | The solar system has an orbital period of 250k years. Nearby
           | systems do not have the same orbital period. I'm not sure
           | galaxies are considered stable to individual stellar systems.
        
             | breck wrote:
             | > The solar system has an orbital period of 250k years.
             | 
             | I thought it was 250 _million_ years, though maybe I 'm
             | misunderstanding you. [1]
             | 
             | [1] https://www.sciencefocus.com/space/how-long-does-it-
             | take-the....
        
               | willis936 wrote:
               | My mistake! I didn't check, but knew the value was in the
               | range of "too long to assume our galactic neighborhood is
               | static or even repeating but too short to not have had
               | potential repetitions show up in Earth geology".
        
       | idlewords wrote:
       | Whatever the thing is, it's clearly an interesting object and the
       | only sane response is to build a big rocket to go chase it. But
       | we don't have our shit together civilizationally and have to wait
       | (and hope) that there's a next one.
       | 
       | This is one reason that I'm such a big fan of robot probes vs.
       | human space flight. If your space program is about flinging tiny
       | cameras into the remotest reaches of the solar system, it's
       | easier to pursue the occasional alien asteroid on short notice
       | than if you're all about getting a can of primates to the next
       | planet over.
        
         | Sosh101 wrote:
         | It was already moving away too quickly once discovered, even if
         | we there had been some kind of craft ready.
        
           | px43 wrote:
           | Presumably it's no longer accelerating though, so it doesn't
           | really matter how fast it's going. I guess the thing is still
           | going to be in our solar system for another 15 years or so,
           | so a solar sail or any number of other options exist to
           | launch something towards it.
           | 
           | https://i4is.org/what-we-do/technical/project-lyra/
           | 
           | https://www.wired.com/story/should-earthlings-chase-
           | oumuamua...
        
           | idlewords wrote:
           | No such thing as too quickly if you've got a motivated
           | planet.
        
       | Taylor_OD wrote:
       | What a hit piece. Interesting read but wow this really feels like
       | one guy is annoyed with another guy and decided to write about
       | him in this thinly veiled article.
        
         | chairmanwow1 wrote:
         | Yeah this article left a pretty sour taste in mouth. Every
         | interview I've heard with Loeb has been pretty interesting and
         | humble as he purports a new theory.
        
       | jzer0cool wrote:
       | A while back there was something known as the _SETI Project_
       | which I could run on my machine. It would collect data from the
       | skies.
       | 
       | I'm curious to know SETI project (or something else) was able to
       | capture any data from the skies as well? The skies are monitored
       | and maybe there is some data, somewhere, as an interesting area
       | for us to all explore.
        
       | arnaudsm wrote:
       | The title implies research on Oumuamua was censored, which was
       | never the case.
        
         | andrewflnr wrote:
         | I think he's just implying that people have been too polite to
         | Loeb before.
        
           | nix23 wrote:
           | So in other articles hes censoring him self (the peoples he
           | wants to be polite with), or has any title of him about
           | another person the word uncensored?
        
             | andrewflnr wrote:
             | It's a clickbait headline, don't overthink it.
        
       | untoxicness wrote:
       | "That Harvard Astronomer" is Avi Loeb.
       | 
       | Loeb was recently a guest on the Lex Fridman podcast where he
       | talked about Oumuamua amongst other things. [0] I found his view
       | on the subject fascinating and his perspective on science
       | refreshing.
       | 
       | [0] https://lexfridman.com/avi-loeb/
        
         | Zigurd wrote:
         | He was interviewed for the Kotke Ride Home podcast. He has a
         | book coming out about Oumuamua. I will probably buy the book
         | because Loeb is apparently brilliant. His evaluation of
         | Oumuamua is very interesting.
         | 
         | BUT the data about Oumuamua is really really tiny. The science
         | of interstellar objects is nascent. Other than to say "If it is
         | a natural object it is super-strange" I am not sure what else
         | there is to say.
         | 
         | In the interview he was articulating theories about it being a
         | cosmic "buoy." So I am anticipating a couple chapters of solid
         | science followed by a lot of speculation, even if it is highly
         | informed speculation.
        
           | throw1234651234 wrote:
           | My concern is that we aren't going to get much more than what
           | was said in the articles already.
           | 
           | I think the beneficial outcome of all of this is that we can
           | identify what to look for next time, and hopefully get
           | funding to do that.
           | 
           | I also wonder if, as our tracking tech gets better, it would
           | be relatively cheap to land a bunch of sensors on these and
           | have them go on a ride somewhere in space for much cheaper
           | than launching our own and trying to accelerate it to that
           | velocity, even considering the costs of interception.
        
             | m4rtink wrote:
             | If you can intercept an interstellar object to land
             | something on it you can by definition also just launch the
             | thing to the same trajectory.
             | 
             | Unless your payload is advanced enough to use the mass of
             | the object for something (fuel, radiation shielding,
             | construction materials, etc.) there is not much benefit in
             | landing on an interstellar object if you just want to
             | launch an interstellar probe.
             | 
             | Maybe actually if you wanted to send a really long range
             | message it could help to put it on an interstellar asteroid
             | - much more likely someone would notice a huge mountain
             | flying through their system than a piano sized piece of
             | metal, even if both hold the same message.
        
               | dysfunction wrote:
               | If you had _really_ good shock absorbers you could
               | intercept at an orthogonal trajectory and have the impact
               | knock you into the desired trajectory... not practical
               | but fun to think about.
        
               | throw1234651234 wrote:
               | The other argument is mass - most of the sensor could
               | bury itself in the mass for safety.
               | 
               | Yes on trajectory, but no on same trajectory, with same
               | mass. Of course, this might be a moot point, because
               | other than hiding from some radiation and micro-scoping
               | impacts, as well as leaching resources (which we aren't
               | really advanced enough to do), there is no benefit.
        
           | akuchling wrote:
           | The Washington Post has a review of the book:
           | https://www.washingtonpost.com/outlook/an-interstellar-
           | accid...
           | 
           | Two excerpts from the review: "While this exotic explanation
           | of the object serves as the backbone of the book, Loeb's
           | broader argument grows out of his bewilderment with the
           | blowback to his hypothesis; he regards it as an omen of
           | imaginative decay and anti-alien bias in the scientific
           | community. ... While it's tantalizing to imagine that
           | 'Oumuamua was our first brush with aliens, Loeb writes most
           | memorably about collecting shells on the beach with his
           | daughters, brainstorming trippy new studies with his many
           | proteges and seeking comfort in the view of the night sky
           | from our lonely planet."
        
             | shrimpx wrote:
             | His scientific perspective very much reminds me of early
             | Einstein's. Refreshingly idealistic and foolish.
        
       | ignoranceprior wrote:
       | What about that Israeli military official who claimed that there
       | was a Galactic Federation of aliens? Could this be one of their
       | probes?
        
         | dqpb wrote:
         | Uh, link please?
        
           | ignoranceprior wrote:
           | https://www.jpost.com/omg/former-israeli-space-security-
           | chie...
        
       | tomiplaz wrote:
       | Here's also a review of Avi Loeb's arguments written and
       | presented by prof David Kipping from the Cool Worlds Lab:
       | https://www.youtube.com/watch?v=qX_Bj7064Ms
        
       | Damorian wrote:
       | I'm just saying, if I wanted to probe every solar system in the
       | galaxy, I'd build a craft with extreme geometry that would fly
       | very close to stars and accelerate for a gravity assist before
       | flying toward the next target star. So it would look exactly like
       | what we saw.
        
         | throw1234651234 wrote:
         | You would have to identify the star that Oumua is going to for
         | that theory to work. Seems like it should be pretty easy to
         | know if it's going to the nearest star (or coming from one),
         | and it's not originated from or going to Alpha Centauri.
         | 
         | The next question is whether or not there is some other logical
         | path that defines logical gravity assists to visit as many
         | stars as possible - nothing like that has been put forward
         | either.
         | 
         | Afaik, it's coming from so far away that we have no idea what
         | star it previously visited.
        
           | Damorian wrote:
           | I don't think it's safe to assume it would come from/go to
           | the nearest stars to us, as the flight path might need
           | extreme changes that aren't in the fuel budget, especially
           | given its already very high speed.
        
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