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.
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.
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.
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.
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.
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.
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."
The guy doesn't even say it's a probe. He thinks it's likely space junk, but not from us. If you lived on some remote island not near shipping or flight lanes, you'd know people were out there because of all the plastic bottles and crap that would show up on the shore. Same thing basically. The beings who made it could have been extinct for millions of years.
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.
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.
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.
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.
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.
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.
>> 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).
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.
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.
Fun fact. Amateur astronomers can use photometry to detect some transiting exoplanets using as small as a 4'' telescope on a night with good seeing. Atmospheric composition is a different matter.
> Those two things weren't readily available until the past few decades...which surprise is when exoplanet discoveries started happening.
I think the other poster might be alluding to a chicken-and-egg situation: could a stronger theoretical basis for the existence of 'Hot Jupiters' have driven development toward the goal of their detection 20 years earlier?
Hot Jupiters were unknown until they were discovered once instruments were sensitive enough to detect them. No major planetary development models predicted them. The current best explanation for them is they formed much further out from their parent stars and migrated inward. The migration phenomena is still poorly understood, it wasn't on anyone's radar in the 70s and 80s.
So until Hot Jupiters were discovered they were not predicted. No one even thought to look for them. No one was thinking about Hot Jupiter detectors that just didn't get funding.
Had billions of dollars flowed into astronomy instead of particle accelerators exoplanets (of all types) might have been discovered earlier. Then again they may not have. It's a pointless "what if".
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.
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.
Is methane really a general purpose biomarker? I thought methane ice was pretty common on astrological bodies, and thus vast majority of methane in the universe is not created by biological processes.
Atmospheric methane on a terrestrial planet would be a biomarker. Bio-suggestion maybe. Free methane in the atmosphere of a planet anywhere near the habitable zone of a star would be readily broken down. If there's a good amount detected it suggests replenishment by biological processes. Biological processes are definitely not the only source of methane. It's enough to warrant more observations or even new instruments.
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:
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.
I listened to Avi on the latest Mindscape podcast. I'm 99% on his side but I would have loved to hear responses to the idea, how do you distinguish this from hunting for ghosts, souls, E.S.P., telepathy, etc... Someone who believed in those things would pretty much make all the same arguments (eg, have an open mind).
I'm sure there are good arguments to distinguish why searching harder in the directions Avi wants things to go is different from searching for ghosts. It would be nice have heard them.
> 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.
>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.
Same, he even went on Planetary Radio on January 27th and said something to the effect of "show me a plausible model that shows this wasn't some sort of craft using a solar sail to accelerate out of the system, I'm happy to be proven wrong".
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.
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.
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.
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.
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.
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.
>> 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.
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 :)
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.
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.
> 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.
>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.
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.
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.
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.
> 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.
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.
> 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.
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.
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”.
> 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.
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.
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.
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?
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.
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.
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.
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:
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.
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.
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.
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.
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.
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.
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.
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."
Gathering more data on this object is essentially impossible right now. There's a telescope coming online soon (LSST) that should detect many more objects like this, though.
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
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.
>> Loeb was a once-respected scientist who made important contributions to astrophysics and cosmology, particularly when it came to black holes and the first stars. But his work on extraterrestrial signatures continues to be largely unappreciated by the community — a position as justifiable as ignoring the comparable idea of Russell’s teapot — and rather than address their scientific objections, he’s stopped listening to other astronomers entirely, instead choosing to try his scientific case in the most unscientific place imaginable: the court of public opinion.
This is an attack piece that targets Avi Loeb's character. It's disturbing that the author of the piece is himself an astrophycisist and I have to wonder, if Avi Loeb is calling upon the court of public opinion, what else is this piece, published in Forbes rather than a science venue, doing exactly?
Science is a debate. For there to be a debate, there have to be differing opinions. And for there to be differing opinions, there has to be the freedom of scientists to express their opinions. Even poorly supported opinions like Avi Loeb's. What hurts science is bombastic invocations of "the large amounts of research done by other professionals who specialize in this particular field" - as an attempt to stiffle an opionion the author is not fond of with an appeal to authority.
I agree and no longer read his articles, and I don't think he provides any value. He often uses statements like this to attack targets, he did the same thing with the last article that came across my news feed for Roger Penrose.
>>Hundreds of scientists have pointed this out to Penrose — repeatedly and consistently over a period of more than 10 years — who continues to ignore the field and plow ahead with his contentions.
I don't think many realize the seriousness of the situation. If the asteroid is just a rock, nothing happens, everything is just fine, we can continue to be the apex predator of Sol system.
But if anybody is wrong and oumuamua was in fact an alien device looking for us (intelligent life), almost certainly it has found us. What happens next is entirely out of human hands, unless we can realize that event.
Maybe is nothing more than some kind of probe or long range satellite, but it could be a scout ship, or an early warning sensor, and we're just in course to meet the rest of the hardware from where oumuamua came from.
Is really rational just plainly deny the chance of that rock being pure luck of not having found a big fleet of some interestellar things and having to figure out if they are friendly or not as they approach the planet?
Probably the space force and the whole stuff many countries are sending to all the solar system since 2018 are just a coincidence, or may be other people is also worried about what happens next if oumuamua was not just a weird rock.
> What happens next is entirely out of human hands, unless we can realize that event.
We would not have been able to detect this object two decades ago. So the "event" is that our observation capabilities have grown past some threshold, not that anything has changed in our solar system. Whether rocks or alien probes, these types of objects must always have been passing through our solar system with some regularity. We'll get a a chance to study others soon enough.
Edit: this video by Scott Manley helps to get a sense of how our ability to detect asteroids has grown over time: https://youtu.be/BKKg4lZ_o-Y
I find it kind of sad how desperate people get for certain outcomes, in this case proof of extraterrestrial life.
Of course we have limited observations of this object. But that doesn't prove anything. Extraordinary claims require extraordinary evidence.
But here's where the desperation comes in: false equivalence. Like we have limited observations so you can't prove it ISN'T an artifact of alien life. Like the outcomes of it being artificial and natural in origin are treated as equal.
It just seems like the worst application and misunderstanding of the anthropic principle ever.
No evidence that it's artificial doesn't mean it's natural. It just means there's no evidence of it being artificial. But absent any evidence, natural origin is the most likely explanation.
I guess I don't understand what the fundamental disagreement is here. Most astronomers believe the probability that Oumuamua was an alien visitor is very small. Loeb's argument is that the probability may be a bit larger. But we'll (very likely) never actually know which it was, so the disagreement is about the unknown likelihood of a single observed event. It just seems obvious that we'll have to settle for "probably a funnily-shaped rock, but there's a small chance it was something more interesting" and live with that.
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[ 3.1 ms ] story [ 164 ms ] threadLoeb 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/
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.
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.
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.
I'm imagining some Vehicle Assembly Building-sized cloud of aerogel with a paperclip-size payload at the center.
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.
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."
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.
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.
https://old.reddit.com/r/askscience/comments/l6xl3d/askscien...
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.
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.
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).
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.
Ya, but if people were allowed to look for hot jupiters in the 70s/80s they would have found the first exoplanet far sooner.
I think the other poster might be alluding to a chicken-and-egg situation: could a stronger theoretical basis for the existence of 'Hot Jupiters' have driven development toward the goal of their detection 20 years earlier?
So until Hot Jupiters were discovered they were not predicted. No one even thought to look for them. No one was thinking about Hot Jupiter detectors that just didn't get funding.
Had billions of dollars flowed into astronomy instead of particle accelerators exoplanets (of all types) might have been discovered earlier. Then again they may not have. It's a pointless "what if".
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.
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.
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
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.
I'm sure there are good arguments to distinguish why searching harder in the directions Avi wants things to go is different from searching for ghosts. It would be nice have heard them.
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.
Same, he even went on Planetary Radio on January 27th and said something to the effect of "show me a plausible model that shows this wasn't some sort of craft using a solar sail to accelerate out of the system, I'm happy to be proven wrong".
https://www.planetary.org/planetary-radio/0127-2021-avi-loeb...
We just have to keep watching, more thoroughly and with better equipment.
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.
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.
But at the same time why shouldn't we continue trying 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.
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.
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.
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.
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.
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.
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.
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.
Mindscape podcast (Sean Carroll) is really good.
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.
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.
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....
'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.
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.
https://youtu.be/4Wrc4fHSCpw
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.
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.
This, along with strange shape made the object interesting for ET speculation.
https://www.sciencefriday.com/episodes/january-22-2021/
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.
https://i4is.org/what-we-do/technical/project-lyra/
https://www.wired.com/story/should-earthlings-chase-oumuamua...
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.
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
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.
This is an attack piece that targets Avi Loeb's character. It's disturbing that the author of the piece is himself an astrophycisist and I have to wonder, if Avi Loeb is calling upon the court of public opinion, what else is this piece, published in Forbes rather than a science venue, doing exactly?
Science is a debate. For there to be a debate, there have to be differing opinions. And for there to be differing opinions, there has to be the freedom of scientists to express their opinions. Even poorly supported opinions like Avi Loeb's. What hurts science is bombastic invocations of "the large amounts of research done by other professionals who specialize in this particular field" - as an attempt to stiffle an opionion the author is not fond of with an appeal to authority.
>>Hundreds of scientists have pointed this out to Penrose — repeatedly and consistently over a period of more than 10 years — who continues to ignore the field and plow ahead with his contentions.
https://www.forbes.com/sites/startswithabang/2021/01/28/the-...
https://www.forbes.com/sites/startswithabang/2020/10/08/no-r...
But if anybody is wrong and oumuamua was in fact an alien device looking for us (intelligent life), almost certainly it has found us. What happens next is entirely out of human hands, unless we can realize that event.
Maybe is nothing more than some kind of probe or long range satellite, but it could be a scout ship, or an early warning sensor, and we're just in course to meet the rest of the hardware from where oumuamua came from.
Is really rational just plainly deny the chance of that rock being pure luck of not having found a big fleet of some interestellar things and having to figure out if they are friendly or not as they approach the planet?
Probably the space force and the whole stuff many countries are sending to all the solar system since 2018 are just a coincidence, or may be other people is also worried about what happens next if oumuamua was not just a weird rock.
We would not have been able to detect this object two decades ago. So the "event" is that our observation capabilities have grown past some threshold, not that anything has changed in our solar system. Whether rocks or alien probes, these types of objects must always have been passing through our solar system with some regularity. We'll get a a chance to study others soon enough.
Edit: this video by Scott Manley helps to get a sense of how our ability to detect asteroids has grown over time: https://youtu.be/BKKg4lZ_o-Y
Of course we have limited observations of this object. But that doesn't prove anything. Extraordinary claims require extraordinary evidence.
But here's where the desperation comes in: false equivalence. Like we have limited observations so you can't prove it ISN'T an artifact of alien life. Like the outcomes of it being artificial and natural in origin are treated as equal.
It just seems like the worst application and misunderstanding of the anthropic principle ever.
No evidence that it's artificial doesn't mean it's natural. It just means there's no evidence of it being artificial. But absent any evidence, natural origin is the most likely explanation.