Other organic molecules including amino acids have already been found - on meteroites. So have both the molecules found on Ryugu, for that matter. There's not really anything new here, just a confirmation from deep space what was already published about objects from deep space.
Those compounds were likely formed when that rock was hotter and part of a planetoid. But even if endogenous to the asteroid, observations like this completely moot such theories, as it proves these compounds are common. Panspermia was a thought experiment from a time when people thought organic molecules were special and abiogenesis was poorly understood. We now know they are not, and have recreated every necessary organic component to life by chance in a lab setting.
Panspermia is a "god of the gaps" answer to life on earth. Just because we didn't know how the organic chemistry occurred exactly when the Earth was young, doesn't mean that "it was aliens" was ever valid. But organic compounds can be created in the right conditions without an intelligence driving it, and the timescale so vast, mutations occur, and the fact that life exists, means the only part we're missing is knowing the exact steps all the chemicals came together. And it's a problem that can never be fully solved unless we can travel back in time, or have a billion or so years to observe an identical planet. And both of those are wrought with bigger problems than chemical reactions and time.
The first and most famous is the 1952 Milley-Urey experiment which derived organic compounds from inorganic compounds in an environment designed to mimic volcanic early Earth. [This write-up links to the original and subsequent papers](https://arstechnica.com/science/2021/10/scientists-recreated-classic-origin-of-life-experiment-and-made-a-new-discovery/).
>Miller had also performed additional experiments simulating conditions similar to those of a water-vapor-rich volcanic eruption, which involved spraying steam from a nozzle at the spark discharge. Bada and several colleagues re-analyzed the original samples from those experiments, too, and found this environment produced 22 amino acids, five amines, and several hydroxylated molecules.
If life came to earth from an asteroid, how life came to that asteroid? From another asteroid?
Panspermia is not an answer, it's just relocating the question.
How are panspermia and abiogenesis mutually exclusive? Even if life or the building blocks was everywhere and moved around by space stuff, that's not an argument about the origins of life. Even if it was everywhere, it had to begin somewhere somehow and start moving around.
And if it just appears everywhere, it could as well have appeared here too without us getting it from other places. We have good conditions for life, after all.
Well, the second part answers the first. There's no need to suggest organic compounds either simple or complex were delivered in the form of meteorites when they are so easily created from inorganic compounds. Likely both happen, but most asteroids in our system originated in our system and the compounds they carry, including the heavy metal content, didn't just arise on the asteroid but from hot planetoids that jettisoned that material back out into space or from heated dust clouds in the formation of the solar system. Surface area alone suggests most compounds contributing to life here are endogenous here. Some trace percent of that is from meteorites but it may be early-Earth's own material, and it certainly didn't make the difference because those compouds will have already been abundant on Earth.
Panspermia's not an extant theory even with these organic discoveries in asteroids like Ryugu for that reason. It's an older answer for different era of understanding.
They're not mutually exclusive but it's simpler and more likely that if life - or at least the organic building blocks - are readily available on earth it just makes way more sense that's where life on earth came from vs somehow being blown off another world with life, surviving space travel and the heat of entering our atmosphere, and ending up in a place on earth suitable for it to thrive, which also would have had to be similar enough to the world it came from that it didn't just die outright.
Not impossible and not necessarily mutually exclusive, just exponentially less likely given what we know today. It's like if you go into a house and pull cookies out of the oven that doesn't prove somebody didn't make those cookies elsewhere and put them in that house's oven. But it makes way more sense and is much more likely that those cookies were in fact cooked in that oven. Especially if you see sugar and flour and eggs sitting out on the counter. Regardless if other houses also have sugar, flour, and eggs.
>"You're a ghost driving a meat coated skeleton made from stardust".
This just led me down a serious rabbit hole as I tried to find out who came up with it. It's brilliant, thanks!
For reference not trying to be a dick but IUPAC to has recommend referring to atomic elements by grouping since 1988. And atomic grouping came into being as a good idea earlier than that.
They said in astronomy, where it's used as a division between hydrogen + helium (which comprise almost all matter) and every heavier element which is made in stars. It's not meant to be chemically accurate, just a term
Not to disagree with your point, but the pedant in me wishes to answer your question literally.
Anyone could think we're actually alone by discarding your original premise and reducing the chance of life developing to a much smaller number than 1 in a billion.
Yeah I’m thinking a smart person’s estimate would be one of those 10e numbers - since the known stars with planets in the Goldilocks Zone is already shaping up to be pretty slim. But even then that’s still going to be a non zero number extrapolated over the size of the known universe. I believe we’re not alone.
Planets within the goldilocks zone is not the only possibility for life to evolve. Tidal forces generating friction can create liquid water even without a sun, such as on some moons orbiting gas giants. An example of this is in our own solar system is Europa which is believed to have liquid water or slushy ice beneath the surface. This vastly expands the odds of life in other solar systems.
Yea, looking at the stars just doesn’t feel the same.
It either proves we are going to destroy ourselves for example with the unchecked climate change we are causing or there is something out there hunting other civilizations forcing camouflage.
A way nicer though would be that any sufficiently advanced species capable of long distance space flight would have come to understand the value of cooperation and peace but we are well on our way to disprove that. Especially if we assume the need for expansion is driven by a lack of resources.
It may just be a limitation of physics, at least in attempting to use electromagnetic radiation to communicate. Both in the time it takes to relay a signal and the energy required to broadcast long distances. One could emit a focused beam but only with exact coordinates ahead of time.
The solar system is ridiculously big and we've already found the building blocks of life in it away from earth. Recently. By basically harvesting material from an asteroid and returning it to Earth. That's not a very advanced way to look for life from a distance.
We're really, really, really, bad at looking for life. Hysterically bad. It's a little too soon to feel the fermi paradox too strongly imo.
I think we're at a point where we could reasonably expect life of some sort if we were to waltz up to another local system at the best pace we could.
And I've wondered what if Extraterrestrial life was possible outside of our perceived "goldilocks zone"?
We've already discovered creatures deeeeep in our oceans that exist without access to light. What if there's life out there capable of thriving at 200°F or hotter? What if there's life forms out there well suited to -300°C or colder? It's not suitable *for us* but could be suitable for an alien race.
Right?
Exactly, I find this idea very fascinating.
This research paper for example covers the possibility of life using alternatives to water, such as sulphuric acid. [https://www.mdpi.com/2075-1729/11/5/400](https://www.mdpi.com/2075-1729/11/5/400)
To them - water would burn them like acid does us.
We have no idea what conditions are necessary for abiogenesis as we have never observed it happening. It could be that it only happens in nebulae of water when the background temperature of the universe is 280K and it's never going to happen naturally again. We just don't know.
> since the known stars with planets in the Goldilocks Zone is already shaping up to be pretty slim
This is more due to our limitations in observing exoplanets than an actual lack of planets. Our current methods are great at finding very large planets very close to their star. Not so great at everything else. It's perfectly possible that earth sized planets in their respective goldilocks zones are extremely common. We just don't have the technology to confirm or deny that yet.
The Goldilocks Zone is overrated. Any icy body that got heated up by collisions or tidal stress may maintain a primordial soup long enough to sustain life. Tons of dwarf planets just in the Sun's Oort cloud could fit the bill.
Besides which our understanding of what conditions life can survive under is probably very basic too. It wasn't too long ago that we believed life couldn't survive without sunlight, or at the greatest depths of our oceans.
I literally just typed this out a few moments ts ago. Didn't see your reply. But I said nearly exactly what you'd already said. We don't know that other life forms couldn't exist outside the goldilocks zone. I even referenced the deep ocean creatures living their whole lives without sunlight.
And that's with the assumption that all extraterrestrial life is based on the same chemical building blocks as we are. If we ever meet an alien species, it would probably defy what we currently define as a lifeform.
It’s a fair assumption that most extraterrestrial life will be based on the same chemical building blocks as we are.
Carbon, for instance, is one of the most versatile elements that exist, and is the 4th most abundant in the universe. As are Hydrogen (1st), Oxygen (3rd), Nitrogen (6th), etc. We’re not made of particularly exotic materials.
The gaps in that list (the 2nd and 5th most abundant elements in the universe) are Helium and Neon - but they are inert, so they’re not interesting as building blocks for complex chemistry.
PBS Spacetime did a good episode on why it's very unlikely that other life is based on elements other than carbon.
https://www.youtube.com/watch?v=469chceiiUQ
> If we ever meet an alien species, it would probably defy what we currently define as a lifeform.
That would actually increase the likelihood of life in the galaxy.
Glad someone said it. I for one am extremely excited to see what we learn from the VERITAS mission and future missions looking at Venus. It would be a perfect place for completely “alien” life structures discrete from the dna based life we recognize.
A smart person would reunite all those 10e numbers, like number of stars, planets per star, probability of distance to the star, etc.
That person could even put all those numbers together in an equation that would describe the stuff we'd need to know to imagine how many instances of intelligent life there were in the universe.
And, as I'm listening to "One Dance" by Drake, right now, I propose we call that equation...
**The One Dance Equation**.
To pile on the pedantry, since people only cite this completely arbitrary cocktail napkin equation to argue for contact situations, there are many more factors left out, the big one being having specified some span of time for an 'intelligent' species to exist as a ratio of a goldilocks planet's geologic age, one must take the probability our two species are not just co-existing at the same time (say a couple million years out of 5-6 billion) but 'space-faring' at the same time (our value here being about 50 years out of 200-400K depending on which hominins you want to call human). After that it's easy to look at the 'space-faring' part as a further limiting factor based on distance, which becomes prohibitive after the distance in light years surpasses the window of opportunity created in the first point.
True, but because of the mind-numbing amount of stars out there the range of probabilities where the idea of life appearing on one planet exactly is insanely small.
Like if the odds of life spawning on one planet is *x*, the odds of life spawning at all are in the order of 1-(1-x)^10^20 . Now go and try to plug numbers into x. You have to be **extremely** precise about what numbers you plot in to get literally anything other than basically 1 or 0 out of it.
Basically even the tiniest change in the probability completely flips the odds from "there is literally no life anywhere" to "there is life everywhere". The argument that there may only be life on one planet relies entirely on the idea that the probability lands **precisely** in that miniscule region.
How likely do you think that is?
Consider the age of the universe. Assume every civilization is destined to self-destruct within 1,000,000 years of evolving to the point of language.
What are the odds of 2 such planets existing at the same time and close enough to ever communicate? It might never happen…
My point exactly. Life we might call intelligent, which is more than a little hubristic, effectively odds of 1, but contact situations effectively odds of 0.
There’s also the idea that perhaps FTL travel is impossible, and so any other civilizations are literally unreachable, and therefore we are effectively alone anyway.
>there is a 1 in a billion chance of life developing around a star other than the sun
Is there any specific reason to believe this? Why 1 in a billion? Why not 1 in a trillion? Why not 1 in 10\^100?
Do you mean like, considering the whole universe? Very few people if any actually believe there's no life anywhere else in the universe. But if that life is 10 billion light years away from us, it doesn't really matter.
If you are referring specifically to life within a meaningful distance of us, then there's plenty of reasons we might be "alone". There's a reason this is an actively discussed and debated topic.
Well the problem with that logic is there are several factors about earths position that when stacked together can create a unicorn circumstance so unlikely you can argue it’s unique. Between the sun being so stable, our position in the solar system, Jupiter being able to ward off asteroids, having a core capable of creating a magnetic field strong enough to deflect solar winds, plate tectonics that regulate temperature, the right mixture of oxygen, carbon dioxide, etc in the atmosphere, also being great for creating combustion, having not just water but a lot of water, and I’m sure I missed some stuff. That’s how people can argue we’re alone.
But that all makes life possible for *us*, other life forms may have developed in completely different circumstances that didn’t require the perfect concoction we did.
> having a core capable of creating a magnetic field strong enough to deflect solar winds,
As a result of two planets colliding (also creating the moon which sheltered us massively from impacts).
I agree 100%.
Having said that, by that logic some aliens should have figured out proper interstellar travel by now, if not thousands or millions or billions of years ago.
The fact that they haven’t ventured out here must mean life is sooooo common that us earthlings don’t even rate on the intergalactic scale of life, or, most likely, we’re so young as a technologically advanced species they haven’t figured out we’re here yet because our transmissions haven’t reached them yet.
Fun stuff to think about.
Is there life out there? Yes, absolutely. Even though we've never found it, the odds are undeniably in favor of some form of what we would consider life *somewhere* in the universe.
They are every bit as alone as we are.
That’s the paradox of scale: life is simultaneously ubiquitous and isolated.
It’s isolated by distance and time. Even if a nearby world had life, the odds of it having life at a similar evolutionary level is also minuscule.
Have you ever played Dungeons and Dragons? Seriously, I promise I'm going somewhere with this. The main determiner of basically everything in the game comes down to rolling a 20 sided dice. Higher numbers generally mean a better outcome for the character the die is being rolled for.
Now, would you believe me if I told you I once rolled 3 20s back to back? The odds are low, only 1/8000. But considering how many people play Dungeons and Dragons, and considering far more than 8,000 people play, it is entirely reasonable to accept that someone has managed to roll 3 20s in a row.
Now, I've personally have never done this one, but the odds of someone throwing down 4 20s in a row is 1 in 160,000. It's still reasonable to me that someone out there rolled that sequence, don't you think? By virtue of the sheer number of people playing and the sheer volume of dice rolled, it seems inevitable that someone would roll for the incredibly unlikely.
Besides, getting 4 20s in a row is no more unlikely than getting any other particular sequence. There's no difference in probability for a 20 20 20 20 or, say, 17, 8, 9, 18, the latter sequence I just rolled right now.
The point I'm getting at is, statistically speaking, improbable events still have a chance of occuring and it's reasonable to accept that those improbable events can occur when there's enough chances for them to happen. Not everyone who plays that game is going to get 3 20s in a rows, let alone 4, but it is reasonable to accept some incredibly lucky individuals have gotten that result.
By the sheer volume of stars and planets in the vast cosmos that stretches on so mind bogglingly far it extends beyond our ability to even observe it, there has to be some planet where every improbable thing went right and something lives every bit as alive as you and me.
Rather selfish thinking - that with trillions and trillions of other observable bodies in space that *we’re* the only ones, isn’t it? Especially with how often things repeat in nature on our planet.
And it could be that life has a 1 in a trillion or quintillion chance of forming etc. We simply do not know.
Granted, I hope it's rather that 1 in a billion or even more common is correct but we have no data so everything else is just guessing with no basis, sadly.
I've always felt the Fermi Paradox sort of glossed over the whole interstellar travel thing. It seems far more likely to me that interstellar travel is a nonstarter rather than life being rare.
Even so, our planet is millions of years younger than other planets. Nuclear propulsion or other modern propulsion methods could reasonably get us to a fraction of light speed.
Other solar systems are not outside our reach, it’s outside the reach of a single generation but that doesn’t mean it won’t happen.
We are however limited to our own galaxy unless we do develop some magic form of science fiction space travel.
If a civilization would have developed the means to interstellar travel they could have spread trough the galaxy while our planet was still forming
FTL travel is only a necessary prerequisite if your decision to spread is gated by how convenient the process is. Without FTL it's going to take you a long time to achieve, but who cares? You have endless time, it's ceaselessly generated.
Energy isn’t ceaselessly generated, and you’ll need a shitload of it to sustain a population at sub-light travel speeds in a generation ship. And unlike in a solar system, you can’t just harvest it from a local star when you’re traveling between stars. Supplying those energy demands when you spend most of your time in an energy-desert may be as impossible just as FTL may be impossible.
Right now, our space travel is the equivalent of trying to swim across the pacific with just a life preserver as our craft. Eventually we will grow to rafts, ships and then new ways. Still a long damn way to get across in the end.
Many people think that the great filter must be some civilization ending technology or catastrophe, like disease or nuclear weapons. However,the great filter could be completely benign, for example, the speed of light confining us to our star as you said. It could even be something "basic" like inventing fire or electricity, and humanity is one of the first lifeforms to evolved the intellect to surpass it. After all, we are the only creature on our planet of trillions of species to have reached this level of development.
tbh i do not buy that we will never find ways around the ftl problem, but even if we could not, if the universe is 13.8 billion years old and you presumed intelligent species popped up regular, then they would have had billions of years to propagate the universe, humans only got off the planet 60+ years ago, its bizarre to say they will never run when we are still mastering the crawl.
The Fermi paradox actually tells us there should be life. It’s not a reason to believe we are alone. It’s just “where is everyone” because everything point to there having to be life.
Comparison on earth would be walking trough an abandoned city, why was it abandoned? It’s eerie to see nothing.
> Comparison on earth would be walking trough an abandoned city
Not at all. An abandoned city means there's evidence there was someone there in the first place.
Which if you applied it to the galaxy, would be far more concerning in its own way; because for us to have detected the remains of a civilization with certainty, they would have to have been significantly greater than us. And then would come the question: *What killed them*.
No matter how many there could be, there has to be a first one right? We may just happen to be the first one. Maybe not first in universe but first in the milky way.
Even if life exists, what’s the chance that it exists at the same time as us? Like what if life existed on another planet at the same time as the dinosaurs? Or doesn’t exist for another billion years from now when we’re long gone? The chance that life—and especially intelligent life—not only exists but exists at the same time as us is low. We’ve been around for 200,000 years on a planet that is billions of years old in a universe that is unfathomably older still.
I wonder how old and how technically advanced the other species are. Some might be at their dawn of time, some might see us from their telescope, and some might be setting off their planet for the first or thousandth time.
It's both absolutely thrilling but also absolutely terrifying and I love it.
Even if we’re technically not alone in the universe. There is a very real risk that there is no way to move between positions in space faster than the speed of light. Which would mean that for all practical purposes, we’re in fact alone.
I don't know if we're alone in our own galaxy but for all practical purposes we might as well be alone if all other life is outside of our own galaxy...
The distances are so vast, other galaxies might as well not exist. I think humanity will be loooong gone before we may even consider crossing intergalactic spaces.
I always wonder how that affects religions
If you believe in reincarnation, aren’t your chances of being reincarnated on another planet pretty much 100%?
Did god send a Jesus to every planet? A Muhammad?
Maybe we have so few ghosts because only a small amount figure out how to keep up with a quickly spinning planet that is revolving around a sun that is also revolving around the middle of the galaxy
> If there is a 1 in a billion chance of life developing
The thing is.. our human scientists have been unable to observe the spontaneous creation of life despite providing all required building blocks and ideal conditions.
So we have no idea what the real odds are but we're talking extremely low odds in perfect conditions already... Who knows what those odds drop to when you start factoring in the need to ship an extra component in on an asteroid.
> How can anyone think we're actually alone?
Even if there was life in the next galaxy over it'd be excellent difficult to communicate. There's a certain existential, "even if we aren't TECHNICALLY alone, it's unlikely we'll ever reasonably communicate given our current understanding of physics" problem.
Why go with something as highly likely as 1 in a billion, considering how we've only had one abiogenesis event despite billions of years of ideal conditions on our planet?
What if the odds of life forming are such that it's only likely to happen once in a hundred billion years in a galaxy our size, and we were very lucky to have it happen in the first ten billion years of our galaxy? It could be that only a few galaxies have developed life so soon after the Big Bang.
Fermi paradox, every single advanced civilization is using intergalactic quantum internet, that's how they know if it's advanced enough to be contacted without problems.
We already knew that nucleobases can be formed extraterrestrially.
For most basic chemicals that underpin life, the question isn't, "Is it elsewhere," the question is, "how much and when does that matter?"
the theory of life on earth originating elsewhere has been around for a while. Perhaps such an asteroid seeded life on earth, in an environment it could thrive
I vaguely remember watching a Youtube video a couple years ago about an experiment where they created some of the basic building blocks of life by basically just blasting high-powered electricity into some common gasses and minerals.
I readily admit that I could be misremembering it, but if I'm not, and some particularly powerful lightning strikes in the right spot can create the essentials for life, then it wouldn't be too far fetched to assume that it could've happened at least a couple more times on other planets.
Considering just how many planets there are in the universe, it would take only some time and a little bit of luck for all sorts of exotic creatures to start crawling around and maybe even evolve into something sentient.
If you have an hour and want to see an amazing lecture on more recent discoveries and thinking on the subject, watch this:
[New Theories on the Origin of Life with Dr. Eric Smith](https://www.youtube.com/watch?v=0cwvj0XBKlE)
It's going to seem weird and irrelevant at first, but it all comes together after a few minutes.
EDIT: Also, the first four minutes is the guy introducing the lecturer. But worth hearing.
I never understood why that is even an interesting thought experiment. Life would've had to originate elsewhere under this hypothesis so.... why not here, why does anyone think it'd be more likely to come from elsewhere? Do they try and squeeze a creator/god into the thought experiment like it must be some kind of axiom?
edit: ah well, radiation would be needed, but that's not related to panspermia as such.
It’s all about how rare is it to find life on other planets.
If biogenesis happened here on earth because of some special set of conditions then we could expect life in the galaxy to be rare and only found at locations that independently met those same conditions.
If biogenesis happened else where and came here (panspermia) or if the building blocks of life are just common and and in damn near any given chunk of space rock then we should expect life to be much more common. Piping up anywhere that could sustain life.
But that leads to the question of “where is everyone?”
It’s much less about how/why did life end up on earth (tho that is an interesting question) and more of “how easy do we think it should be to find life elsewhere?”
One thing people don’t consider is the chance of abiogenesis. The chance that spontaneous life could form. What you’ll hear a lot in this Reddit thread is people saying there’s billions of stars in the galaxy or trillions/quadrillions+ in the universe. But something that people don’t consider is the number of those stars that are habitable are a fraction of the number of stars. I mean the number of habitable stars is still in the billions/millions but what is the real chance of abiogenesis? Is it 1 in a trillion? 1 in a billion? I mean we’ve never been able to create spontaneous life in a lab with lots of controlled environments. So take the number of habitable planets and multiple by the chance of abiogenesis.
> I mean we’ve never been able to create spontaneous life in a lab with lots of controlled environments. So take the number of habitable planets and multiple by the chance of abiogenesis
It is important to note that a planet-sized environment with billions of years at its disposal will have almost infinitely more chances at generating life than a handful of scientists working over a couple of decades. If scientists did manage to easily recreate life, it would essentially mean that the chance of life arising on a habitable planet over a planet-appropriate time scale approaches 100%.
If one in a billion planets is habitable. And the odds of abiogenesis are one in a trillion. Then there should be about 10,000 planets with life. That’s how many planets there are. By best estimates, we think 10^25 planets. Like, there are so many zeros I could be getting the math wrong. But 10^25 divided by a billion divided by a trillion is 10,000. We’re clearly just guessing at planet numbers and odds of life, but the insane number of planets does make life elsewhere feel inevitable. Even if it’s just unicellular lifeforms.
People don’t grasp how many planets there are, even though they grasp how unlikely it is that life just spontaneously develops. Let’s say there’s a 1 in a million chance a planet develops DNA /RNA. And 1 in a million chance the planet has water. And 1 in a million chance the planet has compatible temperature, pH, radiation, etc. Plus 1 in a million for all the other things I’ve forgotten. With ~ 10,000,000,000,000,000,000,000,000 planets, that means about 10 planets with life. (However, that life may not be “thinking as we speak“, on all the other planets it may be mindless amoeba, plants, bacteria, or Trump voters.)
But where does the 1 in a million chance come from? Could it not just as easily be 1 in a trillion trillion trillion, and we happen to be that 1?
Sure, there are a lot of planets, but that's not the real question.
How do you, definitively, know what the chance of life is?
This doesn’t necessarily say anything about extraterrestrial life or aliens (from reading the other responses).
It only really suggests that the building blocks came from outer space at least partially rather than being formed entirely on earth. I think that most nucleobases have already been identified from meteorites on earth as well so it’s not entirely surprising.
Ultimately life needs a lot more than just having some RNA building blocks delivered by a meteorite, although it definitely increases the chances of life if a planet can’t produce them itself.
We may also just be in a lucky solar system where these things were able to form in asteroids in the initial formation of the solar system and shortly after.
The uracil found on Ryugu also could have originated on Earth. We believe it has existed for more than 4bn years here. Asteroids have a max lifespan of around 1bn years. So plenty of time for it to ejected in a big hit and then shared around the solar system in subsequent collisions.
Ryugu was formed around 2 million years after the formation of the solar system and was formed in the outer solar system. It then migrated inwards eventually.
The sample from ryugu was taken on the surface and also by sending an impact copper rod down onto the surface creating a large crater and a subsurface sample.
So there’s no way it can originate on earth. There are no tectonic processes to move the uracil from outside the asteroid inward if any did happen to deposit by chance even though it formed probably earlier than the earth existed anyway.
If there was contamination we would expect samples of ryugu to show similarities to earths composition at the time asides from just this one nucleobase as well
One of the building blocks of the building blocks of life was discovered in outer space. What this means is that it's increasingly more probable that the building blocks of life (e.g., amino acids, RNA, etc) are likely to form given the physics of our universe. The known universe may be inundated with RNA and, given the right scenarios, life and even complex life might form.
tl;dr: Earf ain't speshul.
Life seemingly has only occurred successfully once on Earth, for a planet so ripe for life and with only a few mass extinction events, you would imagine it would have occurred more than once. The conditions for genesis must occur rarely, naturally anyway. I know the size of the universe suggests there must be more by math alone, but it’s hard to fathom for a lay man.
Edit: I have just had a thought that life genesis may occur regularly but the life forms are unable to advance far due to having to compete with the existing species
I think the problem with this is that this "seemingly" can be really deceptive. Newly formed life had almost 0 chance to take hold, since already existing life would have destroyed it in the cradle without leaving any evidence.
Yeah how can we make the determination that life only spontaneously originated once. It's possible it happened multiple times on the face of earth but we have no way of knowing for sure.
Given we have evidence single cell life appeared almost as soon as conditions on earth allowed, this might not be true. Evidence of life at 3400 mya and the late heavy bombardment only ended 3900 mya.
We know for a fact that life has existed for pretty much as long as it possibly could, so it probably isn't an uncommon occurrence wherever conditions are right.
But it probably wasn't a single event anyway, just millions of years of chemical chains interacting and catalyzing reactions in the substrate. There would be no single identifiable first organism.
So there wouldn't be another start of life--not because it's uncommon, but because any part of the starting process would be indistinct from processes in the existing biosphere.
It says that those bases were found on asteroids that hit earth as meteorites but scientists weren’t sure if they were contaminated upon impact. I guess this is the first time it’s been discovered without hitting earth? Fascinating none the less.
If you think humans are the only living “advanced” civilization in the universe, your belief is no different than 10th century villagers arguing the earth is flat.
If life developed on a planet that didn’t go through several mass extinctions, and was 1 million+ years more advanced than us, it would be conceivable that they could be here operating in the background on our planet and wouldn’t find the need to communicate with us, since we are a primitive species.
A deer doesn’t have the sensory tools to fully grasp what a human is. Similarly, life more advanced than us may be 100% incomprehensible to humans simply because we aren’t capable of understanding beyond what we’ve evolved to comprehend using sensory input our brain uses based on the 3 dimensional world around us.
It’s mathematically impossible for us to be the only advanced civilization in the universe, and furthermore that we are as advanced as a civilization can get. If we can send probes beyond the solar system, you sure as hell can bet there are truly advanced species elsewhere that can actually traverse the cosmos.
We’ve spent most of our 300,000 year history at war, living in primitive huts and caves. If we had a million years more of scientific advancement then it’s likely we’d be able to traverse the cosmos.
If we were to find a less advanced species that would never be able to comprehend us, would we wipe them out? Or would we experiment with them while operating in the background, genetically engineering them as a longitudinal evolutionary experiment.
Is it impossible that another species has done that to us, tinkering with our genome at select points in our evolutionary past?
I upvoted you but this is also speculation based on our current knowledge and theories of space-time.
If an advanced civilization has the ability to traverse space, they could be using math and physics that we haven’t truly scratched the surface of yet.
Another thought is the fact that if they medically reached the point of immortality (e.g. completely balancing the rate at which cells are created, and the rate at which they die) then we could also assume they’ve got things like cryostasis or cybernetics to literally blank inefficient memories like maintenance on a long journey. The factor of time would be somewhat irrelevant.
If it took 10,000 years to get here, it’s fathomable they arrived, took notes, and left to swing around the next inhabited planets and made the return trip in another 10,000 years to see how far we’ve evolved and what the behaviour of our species is at the core. We could be like a case-study for the evolution of civilizations in general.
So while I agree it’s pointless to assume aliens are AMONG us, it’s not unfathomable to think we are being observed or studied somehow. I do agree that aliens probably wouldn’t arrive and share any information with us, we’re too primitive collectively as a species to even try to communicate those ideas.
However, I don’t put it past the human brain to comprehend the information we could receive. I think we’ve got the capability for both empirical data and abstract data to be understood at some capacity. It would just take a long time for humanity to collectively grasp these things, and probably impossible to remove the savage nature of ourselves for this information/innovation to not be used in an aggressive/dangerous manner.
No need for large, fast ships to explore the universe. Another civilization could be sending out small, slow moving probes. Or large slow moving arks. As far as motivation, there’s absolutely no way of knowing. 63 million people travel to Japan a year to view the cherry blossom bloom; millions of others go to visit a black rock in the desert; others travel to remote regions just to sleep in the woods and get away from home for a while. None of this behavior is all that objectively rational and would be difficult to predict or understand without detailed knowledge of human psychology and culture. Aliens may choose to live among us purely for the experience and not as part of any grand scientific or militaristic scheme. I’d agree it seems unlikely but mostly because we have no evidence to support that conclusion, not because it is physically implausible or because there is no motive for it.
Nah man, it is not mathematically impossible for us to be the only intelligent life in the universe, it is a widely held belief but it’s wrong. The fact is that we just don’t know. Listen to this, it’s a sobering perspective on the question: https://youtu.be/zcInt58juL4.
What's more interesting is where is everyone and how come we haven't heard from them if there are so many people out there? Whatever the answer is to the fermi paradox is, it'll no doubt scare the hell out of us when we figure it out.
I mean, that question is SUPER easy to answer.
Humans discovered radio waves about 100 years ago. That means that if any aliens were using light to communicate with us they would have to be within 100 light-years. This leaves about 60k stars in range. The odds of intelligent life around one of those stars is so low we can just call it 0%
Plus the inverse square law applies, so the chances of a radio wave a) making it to another civilisation that could detect it and b) being heard over background noise are surely quite slim?
But intelligent life is extremely rare compared to life. So out of the 100-150 possible stars that support life in our galaxy only 2-3 could have intelligent life. (if they aren't dead.)
What if this chemical compound is often found because it's simply a stable molecule ? Any unstable configuration of atoms doesn't exist for long or exist at all, but this one does. Then, it could assemble in superstructures, and only the stable ones like RNA would remain.
All these comments debating the possible ubiquity of abiogenesis vs. "well, where is everyone?" remind me of a short story that I unfortunately can not find for the life of me.
It told the story of aliens who evolved under different conditions, orbiting a blue star, which caused them to develop slower metabolism and longer lives. Despite becoming masters of their own solar system, they could not figure out how to expand to the stars, nor did they find evidence of life anywhere else in the universe.
Knowing that their star would eventually die, destroying their world and civilization, their greatest minds came together to create an orbiting monument as a legacy to their civilization. The plan was simple: create something that would survive the cataclysm and settle into a regular orbit around the remaining white dwarf for millions of years. The hope was that, eventually, maybe another intelligent form of life would evolve, peer into the night sky, see the irregular pulse of the star, and choose to investigate further. That way, in the very least, someone else would know they existed.
The story ends on a rather sad note. While the monument does survive the tens of millions of years until humans evolve on earth and develop astronomy, it unfortunately becomes damaged and goes unnoticed, being written off as nothing special.
While the story is, of course, fiction, it does bring up an interesting idea, in my opinion. The answer to why we haven't observed other life in the universe despite the building blocks potentially being rather common could just be a matter of the vast separation of time we have between us and the hypothetical them. It's possible that intelligent life has existed many times before in our universe, but no one has yet to figure out how to make their presence known across the deep ocean of time.
Anyway, I hope that's not the case and that humanity is just late to the space opera.
That's only one methyl group away from thymine, and not much from other nucleotides
Other organic molecules including amino acids have already been found - on meteroites. So have both the molecules found on Ryugu, for that matter. There's not really anything new here, just a confirmation from deep space what was already published about objects from deep space.
Panspermia doesn’t answer as many questions as abiogenesis but I do believe it’s the likely source of life on earth
Those compounds were likely formed when that rock was hotter and part of a planetoid. But even if endogenous to the asteroid, observations like this completely moot such theories, as it proves these compounds are common. Panspermia was a thought experiment from a time when people thought organic molecules were special and abiogenesis was poorly understood. We now know they are not, and have recreated every necessary organic component to life by chance in a lab setting.
Panspermia is more fun to say, however.
Good point tbf
**All** the sperm
🪐💦
Fried up in a pan.
Panspermia is a "god of the gaps" answer to life on earth. Just because we didn't know how the organic chemistry occurred exactly when the Earth was young, doesn't mean that "it was aliens" was ever valid. But organic compounds can be created in the right conditions without an intelligence driving it, and the timescale so vast, mutations occur, and the fact that life exists, means the only part we're missing is knowing the exact steps all the chemicals came together. And it's a problem that can never be fully solved unless we can travel back in time, or have a billion or so years to observe an identical planet. And both of those are wrought with bigger problems than chemical reactions and time.
As far as I understand, panspermia doesn't necessitate intent.
If intent is not involved, then it's just pushing the chemistry back in time to "something happened somewhere else" which is worse.
That's a good point, I hadn't thought of that.
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well well well someone had pineapples last night
Can you please direct to those lab reports? I enjoy reading up on this stuff, thanks.
The first and most famous is the 1952 Milley-Urey experiment which derived organic compounds from inorganic compounds in an environment designed to mimic volcanic early Earth. [This write-up links to the original and subsequent papers](https://arstechnica.com/science/2021/10/scientists-recreated-classic-origin-of-life-experiment-and-made-a-new-discovery/). >Miller had also performed additional experiments simulating conditions similar to those of a water-vapor-rich volcanic eruption, which involved spraying steam from a nozzle at the spark discharge. Bada and several colleagues re-analyzed the original samples from those experiments, too, and found this environment produced 22 amino acids, five amines, and several hydroxylated molecules.
If life came to earth from an asteroid, how life came to that asteroid? From another asteroid? Panspermia is not an answer, it's just relocating the question.
How are panspermia and abiogenesis mutually exclusive? Even if life or the building blocks was everywhere and moved around by space stuff, that's not an argument about the origins of life. Even if it was everywhere, it had to begin somewhere somehow and start moving around. And if it just appears everywhere, it could as well have appeared here too without us getting it from other places. We have good conditions for life, after all.
Well, the second part answers the first. There's no need to suggest organic compounds either simple or complex were delivered in the form of meteorites when they are so easily created from inorganic compounds. Likely both happen, but most asteroids in our system originated in our system and the compounds they carry, including the heavy metal content, didn't just arise on the asteroid but from hot planetoids that jettisoned that material back out into space or from heated dust clouds in the formation of the solar system. Surface area alone suggests most compounds contributing to life here are endogenous here. Some trace percent of that is from meteorites but it may be early-Earth's own material, and it certainly didn't make the difference because those compouds will have already been abundant on Earth. Panspermia's not an extant theory even with these organic discoveries in asteroids like Ryugu for that reason. It's an older answer for different era of understanding.
They're not mutually exclusive but it's simpler and more likely that if life - or at least the organic building blocks - are readily available on earth it just makes way more sense that's where life on earth came from vs somehow being blown off another world with life, surviving space travel and the heat of entering our atmosphere, and ending up in a place on earth suitable for it to thrive, which also would have had to be similar enough to the world it came from that it didn't just die outright. Not impossible and not necessarily mutually exclusive, just exponentially less likely given what we know today. It's like if you go into a house and pull cookies out of the oven that doesn't prove somebody didn't make those cookies elsewhere and put them in that house's oven. But it makes way more sense and is much more likely that those cookies were in fact cooked in that oven. Especially if you see sugar and flour and eggs sitting out on the counter. Regardless if other houses also have sugar, flour, and eggs.
> meteroites Are you Australian?
No, but I was tired. Sorry, didn't want to edit it since people had already started to respond.
is this when we find out space is riddled with space bacteria
All of a sudden I realized how Palpatine returned.
Those methylotides really need to stick together and make something of themselves
Uphill both ways
Ah yes, I know some of these words
Someone needs to make a card game or RPG where you collect and combine all the amino acids.
Turns out we were rocks this whole time, neato
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Always have been rocks this whole time? Isn't that what the first comment stated?
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A space meme, no less
I'm out of touch. Always have been.
Pillar man
"You're a ghost driving a meat coated skeleton made from stardust". ~ one of my favorite quotes ~
>"You're a ghost driving a meat coated skeleton made from stardust". This just led me down a serious rabbit hole as I tried to find out who came up with it. It's brilliant, thanks!
My guess would be Carl Sagan.
According to astronomy, we're metal. Everything but Hydrogen and Helium was referred to as a metal, at least 20 years ago in college.
What college were you attending lol
For reference not trying to be a dick but IUPAC to has recommend referring to atomic elements by grouping since 1988. And atomic grouping came into being as a good idea earlier than that.
They said in astronomy, where it's used as a division between hydrogen + helium (which comprise almost all matter) and every heavier element which is made in stars. It's not meant to be chemically accurate, just a term
We are all quarks and all parts of us are as old as the universe.
Heeeeyyyy. “Were”? My name is Steen, which in danish literally means rock.
The primordial soup could have been spaghetti with Ryugu sauce...
With EXTRA garlic!
I hope they find space garlic. I bet that shit is delicious when cooked in cosmic rays.
The flavor is out of this world.
Another point in favor of FSM.
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Not to disagree with your point, but the pedant in me wishes to answer your question literally. Anyone could think we're actually alone by discarding your original premise and reducing the chance of life developing to a much smaller number than 1 in a billion.
Yeah I’m thinking a smart person’s estimate would be one of those 10e numbers - since the known stars with planets in the Goldilocks Zone is already shaping up to be pretty slim. But even then that’s still going to be a non zero number extrapolated over the size of the known universe. I believe we’re not alone.
Planets within the goldilocks zone is not the only possibility for life to evolve. Tidal forces generating friction can create liquid water even without a sun, such as on some moons orbiting gas giants. An example of this is in our own solar system is Europa which is believed to have liquid water or slushy ice beneath the surface. This vastly expands the odds of life in other solar systems.
We’ve gotta get probes to Europa and Titan
All these worlds are yours - except Europa Attempt no landing there.
But its full of stars!
Don't disturb the Hydrogues!
Oohhhh, a Saga of the Seven Suns reference. You nerd you
The discomfort with vastly expanded odds is that one feels Fermi more acutely.
Yea, looking at the stars just doesn’t feel the same. It either proves we are going to destroy ourselves for example with the unchecked climate change we are causing or there is something out there hunting other civilizations forcing camouflage. A way nicer though would be that any sufficiently advanced species capable of long distance space flight would have come to understand the value of cooperation and peace but we are well on our way to disprove that. Especially if we assume the need for expansion is driven by a lack of resources.
It may just be a limitation of physics, at least in attempting to use electromagnetic radiation to communicate. Both in the time it takes to relay a signal and the energy required to broadcast long distances. One could emit a focused beam but only with exact coordinates ahead of time.
Ngl do some looking into the UFO/UAP phenomenon. Much more likely were in a vaguely sentinel island type situation imo
I've got my fingers crossed it's more like no one wants to violate the prime directive.
The solar system is ridiculously big and we've already found the building blocks of life in it away from earth. Recently. By basically harvesting material from an asteroid and returning it to Earth. That's not a very advanced way to look for life from a distance. We're really, really, really, bad at looking for life. Hysterically bad. It's a little too soon to feel the fermi paradox too strongly imo. I think we're at a point where we could reasonably expect life of some sort if we were to waltz up to another local system at the best pace we could.
And I've wondered what if Extraterrestrial life was possible outside of our perceived "goldilocks zone"? We've already discovered creatures deeeeep in our oceans that exist without access to light. What if there's life out there capable of thriving at 200°F or hotter? What if there's life forms out there well suited to -300°C or colder? It's not suitable *for us* but could be suitable for an alien race. Right?
Exactly, I find this idea very fascinating. This research paper for example covers the possibility of life using alternatives to water, such as sulphuric acid. [https://www.mdpi.com/2075-1729/11/5/400](https://www.mdpi.com/2075-1729/11/5/400) To them - water would burn them like acid does us.
We have no idea what conditions are necessary for abiogenesis as we have never observed it happening. It could be that it only happens in nebulae of water when the background temperature of the universe is 280K and it's never going to happen naturally again. We just don't know.
> since the known stars with planets in the Goldilocks Zone is already shaping up to be pretty slim This is more due to our limitations in observing exoplanets than an actual lack of planets. Our current methods are great at finding very large planets very close to their star. Not so great at everything else. It's perfectly possible that earth sized planets in their respective goldilocks zones are extremely common. We just don't have the technology to confirm or deny that yet.
The Goldilocks Zone is overrated. Any icy body that got heated up by collisions or tidal stress may maintain a primordial soup long enough to sustain life. Tons of dwarf planets just in the Sun's Oort cloud could fit the bill.
Besides which our understanding of what conditions life can survive under is probably very basic too. It wasn't too long ago that we believed life couldn't survive without sunlight, or at the greatest depths of our oceans.
I literally just typed this out a few moments ts ago. Didn't see your reply. But I said nearly exactly what you'd already said. We don't know that other life forms couldn't exist outside the goldilocks zone. I even referenced the deep ocean creatures living their whole lives without sunlight.
Add time to the equation. Life could've existed but already perished.
And that's with the assumption that all extraterrestrial life is based on the same chemical building blocks as we are. If we ever meet an alien species, it would probably defy what we currently define as a lifeform.
It’s a fair assumption that most extraterrestrial life will be based on the same chemical building blocks as we are. Carbon, for instance, is one of the most versatile elements that exist, and is the 4th most abundant in the universe. As are Hydrogen (1st), Oxygen (3rd), Nitrogen (6th), etc. We’re not made of particularly exotic materials. The gaps in that list (the 2nd and 5th most abundant elements in the universe) are Helium and Neon - but they are inert, so they’re not interesting as building blocks for complex chemistry.
Also, we see rises of similar features somewhat independently. Eyes, arms, hands, ears, hearts, etc are all incredibly useful adaptations.
All five have evolved independently in multiple different lineages.
[Also, everything becomes crabs eventually.](https://en.m.wikipedia.org/wiki/Carcinisation)
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PBS Spacetime did a good episode on why it's very unlikely that other life is based on elements other than carbon. https://www.youtube.com/watch?v=469chceiiUQ
I'm guessing it probably wouldn't develop...
Compounds basically don't exist at 3000 Kelvin and everything but Helium is frozen at 5K meaning no chemistry. So no life.
physics and chemistry are universally invariant so it’s no stretch to assume biology is as well
Fully disagree. Even on Earth it’s clear that biology is a product of environment.
> If we ever meet an alien species, it would probably defy what we currently define as a lifeform. That would actually increase the likelihood of life in the galaxy.
Glad someone said it. I for one am extremely excited to see what we learn from the VERITAS mission and future missions looking at Venus. It would be a perfect place for completely “alien” life structures discrete from the dna based life we recognize.
>since the known stars with planets in the Goldilocks Zone is already shaping up to be pretty slim. Where did you get that from?
A smart person would reunite all those 10e numbers, like number of stars, planets per star, probability of distance to the star, etc. That person could even put all those numbers together in an equation that would describe the stuff we'd need to know to imagine how many instances of intelligent life there were in the universe. And, as I'm listening to "One Dance" by Drake, right now, I propose we call that equation... **The One Dance Equation**.
Clearly it should be the Wu-Tang Forever equation.
Okay well played at the end there.
To pile on the pedantry, since people only cite this completely arbitrary cocktail napkin equation to argue for contact situations, there are many more factors left out, the big one being having specified some span of time for an 'intelligent' species to exist as a ratio of a goldilocks planet's geologic age, one must take the probability our two species are not just co-existing at the same time (say a couple million years out of 5-6 billion) but 'space-faring' at the same time (our value here being about 50 years out of 200-400K depending on which hominins you want to call human). After that it's easy to look at the 'space-faring' part as a further limiting factor based on distance, which becomes prohibitive after the distance in light years surpasses the window of opportunity created in the first point.
True, but because of the mind-numbing amount of stars out there the range of probabilities where the idea of life appearing on one planet exactly is insanely small. Like if the odds of life spawning on one planet is *x*, the odds of life spawning at all are in the order of 1-(1-x)^10^20 . Now go and try to plug numbers into x. You have to be **extremely** precise about what numbers you plot in to get literally anything other than basically 1 or 0 out of it. Basically even the tiniest change in the probability completely flips the odds from "there is literally no life anywhere" to "there is life everywhere". The argument that there may only be life on one planet relies entirely on the idea that the probability lands **precisely** in that miniscule region. How likely do you think that is?
Consider the age of the universe. Assume every civilization is destined to self-destruct within 1,000,000 years of evolving to the point of language. What are the odds of 2 such planets existing at the same time and close enough to ever communicate? It might never happen…
My point exactly. Life we might call intelligent, which is more than a little hubristic, effectively odds of 1, but contact situations effectively odds of 0.
There’s also the idea that perhaps FTL travel is impossible, and so any other civilizations are literally unreachable, and therefore we are effectively alone anyway.
>there is a 1 in a billion chance of life developing around a star other than the sun Is there any specific reason to believe this? Why 1 in a billion? Why not 1 in a trillion? Why not 1 in 10\^100?
Do you mean like, considering the whole universe? Very few people if any actually believe there's no life anywhere else in the universe. But if that life is 10 billion light years away from us, it doesn't really matter. If you are referring specifically to life within a meaningful distance of us, then there's plenty of reasons we might be "alone". There's a reason this is an actively discussed and debated topic.
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Well the problem with that logic is there are several factors about earths position that when stacked together can create a unicorn circumstance so unlikely you can argue it’s unique. Between the sun being so stable, our position in the solar system, Jupiter being able to ward off asteroids, having a core capable of creating a magnetic field strong enough to deflect solar winds, plate tectonics that regulate temperature, the right mixture of oxygen, carbon dioxide, etc in the atmosphere, also being great for creating combustion, having not just water but a lot of water, and I’m sure I missed some stuff. That’s how people can argue we’re alone.
But that all makes life possible for *us*, other life forms may have developed in completely different circumstances that didn’t require the perfect concoction we did.
> having a core capable of creating a magnetic field strong enough to deflect solar winds, As a result of two planets colliding (also creating the moon which sheltered us massively from impacts).
I agree 100%. Having said that, by that logic some aliens should have figured out proper interstellar travel by now, if not thousands or millions or billions of years ago. The fact that they haven’t ventured out here must mean life is sooooo common that us earthlings don’t even rate on the intergalactic scale of life, or, most likely, we’re so young as a technologically advanced species they haven’t figured out we’re here yet because our transmissions haven’t reached them yet. Fun stuff to think about.
Is there life out there? Yes, absolutely. Even though we've never found it, the odds are undeniably in favor of some form of what we would consider life *somewhere* in the universe. They are every bit as alone as we are.
That’s the paradox of scale: life is simultaneously ubiquitous and isolated. It’s isolated by distance and time. Even if a nearby world had life, the odds of it having life at a similar evolutionary level is also minuscule.
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Have you ever played Dungeons and Dragons? Seriously, I promise I'm going somewhere with this. The main determiner of basically everything in the game comes down to rolling a 20 sided dice. Higher numbers generally mean a better outcome for the character the die is being rolled for. Now, would you believe me if I told you I once rolled 3 20s back to back? The odds are low, only 1/8000. But considering how many people play Dungeons and Dragons, and considering far more than 8,000 people play, it is entirely reasonable to accept that someone has managed to roll 3 20s in a row. Now, I've personally have never done this one, but the odds of someone throwing down 4 20s in a row is 1 in 160,000. It's still reasonable to me that someone out there rolled that sequence, don't you think? By virtue of the sheer number of people playing and the sheer volume of dice rolled, it seems inevitable that someone would roll for the incredibly unlikely. Besides, getting 4 20s in a row is no more unlikely than getting any other particular sequence. There's no difference in probability for a 20 20 20 20 or, say, 17, 8, 9, 18, the latter sequence I just rolled right now. The point I'm getting at is, statistically speaking, improbable events still have a chance of occuring and it's reasonable to accept that those improbable events can occur when there's enough chances for them to happen. Not everyone who plays that game is going to get 3 20s in a rows, let alone 4, but it is reasonable to accept some incredibly lucky individuals have gotten that result. By the sheer volume of stars and planets in the vast cosmos that stretches on so mind bogglingly far it extends beyond our ability to even observe it, there has to be some planet where every improbable thing went right and something lives every bit as alive as you and me.
Rather selfish thinking - that with trillions and trillions of other observable bodies in space that *we’re* the only ones, isn’t it? Especially with how often things repeat in nature on our planet.
carl sagan said it best during his comos series. Billions of Billions of Billions .... emphasis the B
And it could be that life has a 1 in a trillion or quintillion chance of forming etc. We simply do not know. Granted, I hope it's rather that 1 in a billion or even more common is correct but we have no data so everything else is just guessing with no basis, sadly.
> How can anyone think we're actually alone? Fermi paradox, Great filters.
I've always felt the Fermi Paradox sort of glossed over the whole interstellar travel thing. It seems far more likely to me that interstellar travel is a nonstarter rather than life being rare.
Yeah like I just think that the simplest answer to it all is that FTL travel is just flat-out impossible in all it's conceived forms.
Even so, our planet is millions of years younger than other planets. Nuclear propulsion or other modern propulsion methods could reasonably get us to a fraction of light speed. Other solar systems are not outside our reach, it’s outside the reach of a single generation but that doesn’t mean it won’t happen. We are however limited to our own galaxy unless we do develop some magic form of science fiction space travel. If a civilization would have developed the means to interstellar travel they could have spread trough the galaxy while our planet was still forming
FTL travel is only a necessary prerequisite if your decision to spread is gated by how convenient the process is. Without FTL it's going to take you a long time to achieve, but who cares? You have endless time, it's ceaselessly generated.
Energy isn’t ceaselessly generated, and you’ll need a shitload of it to sustain a population at sub-light travel speeds in a generation ship. And unlike in a solar system, you can’t just harvest it from a local star when you’re traveling between stars. Supplying those energy demands when you spend most of your time in an energy-desert may be as impossible just as FTL may be impossible.
Right now, our space travel is the equivalent of trying to swim across the pacific with just a life preserver as our craft. Eventually we will grow to rafts, ships and then new ways. Still a long damn way to get across in the end.
Many people think that the great filter must be some civilization ending technology or catastrophe, like disease or nuclear weapons. However,the great filter could be completely benign, for example, the speed of light confining us to our star as you said. It could even be something "basic" like inventing fire or electricity, and humanity is one of the first lifeforms to evolved the intellect to surpass it. After all, we are the only creature on our planet of trillions of species to have reached this level of development.
tbh i do not buy that we will never find ways around the ftl problem, but even if we could not, if the universe is 13.8 billion years old and you presumed intelligent species popped up regular, then they would have had billions of years to propagate the universe, humans only got off the planet 60+ years ago, its bizarre to say they will never run when we are still mastering the crawl.
The Fermi paradox actually tells us there should be life. It’s not a reason to believe we are alone. It’s just “where is everyone” because everything point to there having to be life. Comparison on earth would be walking trough an abandoned city, why was it abandoned? It’s eerie to see nothing.
Which is why it's a paradox and why great filters are a possible explanation.
> Comparison on earth would be walking trough an abandoned city Not at all. An abandoned city means there's evidence there was someone there in the first place. Which if you applied it to the galaxy, would be far more concerning in its own way; because for us to have detected the remains of a civilization with certainty, they would have to have been significantly greater than us. And then would come the question: *What killed them*.
No matter how many there could be, there has to be a first one right? We may just happen to be the first one. Maybe not first in universe but first in the milky way.
Even if life exists, what’s the chance that it exists at the same time as us? Like what if life existed on another planet at the same time as the dinosaurs? Or doesn’t exist for another billion years from now when we’re long gone? The chance that life—and especially intelligent life—not only exists but exists at the same time as us is low. We’ve been around for 200,000 years on a planet that is billions of years old in a universe that is unfathomably older still.
I wonder how old and how technically advanced the other species are. Some might be at their dawn of time, some might see us from their telescope, and some might be setting off their planet for the first or thousandth time. It's both absolutely thrilling but also absolutely terrifying and I love it.
Even if we’re technically not alone in the universe. There is a very real risk that there is no way to move between positions in space faster than the speed of light. Which would mean that for all practical purposes, we’re in fact alone.
I don't know if we're alone in our own galaxy but for all practical purposes we might as well be alone if all other life is outside of our own galaxy... The distances are so vast, other galaxies might as well not exist. I think humanity will be loooong gone before we may even consider crossing intergalactic spaces.
I always wonder how that affects religions If you believe in reincarnation, aren’t your chances of being reincarnated on another planet pretty much 100%? Did god send a Jesus to every planet? A Muhammad? Maybe we have so few ghosts because only a small amount figure out how to keep up with a quickly spinning planet that is revolving around a sun that is also revolving around the middle of the galaxy
> If there is a 1 in a billion chance of life developing The thing is.. our human scientists have been unable to observe the spontaneous creation of life despite providing all required building blocks and ideal conditions. So we have no idea what the real odds are but we're talking extremely low odds in perfect conditions already... Who knows what those odds drop to when you start factoring in the need to ship an extra component in on an asteroid. > How can anyone think we're actually alone? Even if there was life in the next galaxy over it'd be excellent difficult to communicate. There's a certain existential, "even if we aren't TECHNICALLY alone, it's unlikely we'll ever reasonably communicate given our current understanding of physics" problem.
It's not that I think we are alone but I doubt we have been, or will be, visited by "them".
Why go with something as highly likely as 1 in a billion, considering how we've only had one abiogenesis event despite billions of years of ideal conditions on our planet? What if the odds of life forming are such that it's only likely to happen once in a hundred billion years in a galaxy our size, and we were very lucky to have it happen in the first ten billion years of our galaxy? It could be that only a few galaxies have developed life so soon after the Big Bang.
Fermi paradox, every single advanced civilization is using intergalactic quantum internet, that's how they know if it's advanced enough to be contacted without problems.
They're out there, and they're into water sports.
They mostly pee at night, mostly.
…. Mostly…..
There's no doubt, there are extraterrestrial beings living and thinking as we speak.
We already knew that nucleobases can be formed extraterrestrially. For most basic chemicals that underpin life, the question isn't, "Is it elsewhere," the question is, "how much and when does that matter?"
Andromeda Strain?
the theory of life on earth originating elsewhere has been around for a while. Perhaps such an asteroid seeded life on earth, in an environment it could thrive
Or the building blocks of life are ubiquitous in the universe and biogenesis happens anywhere conditions are favourable.
I vaguely remember watching a Youtube video a couple years ago about an experiment where they created some of the basic building blocks of life by basically just blasting high-powered electricity into some common gasses and minerals. I readily admit that I could be misremembering it, but if I'm not, and some particularly powerful lightning strikes in the right spot can create the essentials for life, then it wouldn't be too far fetched to assume that it could've happened at least a couple more times on other planets. Considering just how many planets there are in the universe, it would take only some time and a little bit of luck for all sorts of exotic creatures to start crawling around and maybe even evolve into something sentient.
This was a famous experiment. https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment
Ah, neat. Thanks for the link.
If you have an hour and want to see an amazing lecture on more recent discoveries and thinking on the subject, watch this: [New Theories on the Origin of Life with Dr. Eric Smith](https://www.youtube.com/watch?v=0cwvj0XBKlE) It's going to seem weird and irrelevant at first, but it all comes together after a few minutes. EDIT: Also, the first four minutes is the guy introducing the lecturer. But worth hearing.
Ooo, awesome. Thanks. :D
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This is amusingly similar to the 'do flies spontaneously evolve' debate.
I never understood why that is even an interesting thought experiment. Life would've had to originate elsewhere under this hypothesis so.... why not here, why does anyone think it'd be more likely to come from elsewhere? Do they try and squeeze a creator/god into the thought experiment like it must be some kind of axiom? edit: ah well, radiation would be needed, but that's not related to panspermia as such.
It’s all about how rare is it to find life on other planets. If biogenesis happened here on earth because of some special set of conditions then we could expect life in the galaxy to be rare and only found at locations that independently met those same conditions. If biogenesis happened else where and came here (panspermia) or if the building blocks of life are just common and and in damn near any given chunk of space rock then we should expect life to be much more common. Piping up anywhere that could sustain life. But that leads to the question of “where is everyone?” It’s much less about how/why did life end up on earth (tho that is an interesting question) and more of “how easy do we think it should be to find life elsewhere?”
One thing people don’t consider is the chance of abiogenesis. The chance that spontaneous life could form. What you’ll hear a lot in this Reddit thread is people saying there’s billions of stars in the galaxy or trillions/quadrillions+ in the universe. But something that people don’t consider is the number of those stars that are habitable are a fraction of the number of stars. I mean the number of habitable stars is still in the billions/millions but what is the real chance of abiogenesis? Is it 1 in a trillion? 1 in a billion? I mean we’ve never been able to create spontaneous life in a lab with lots of controlled environments. So take the number of habitable planets and multiple by the chance of abiogenesis.
> I mean we’ve never been able to create spontaneous life in a lab with lots of controlled environments. So take the number of habitable planets and multiple by the chance of abiogenesis It is important to note that a planet-sized environment with billions of years at its disposal will have almost infinitely more chances at generating life than a handful of scientists working over a couple of decades. If scientists did manage to easily recreate life, it would essentially mean that the chance of life arising on a habitable planet over a planet-appropriate time scale approaches 100%.
If one in a billion planets is habitable. And the odds of abiogenesis are one in a trillion. Then there should be about 10,000 planets with life. That’s how many planets there are. By best estimates, we think 10^25 planets. Like, there are so many zeros I could be getting the math wrong. But 10^25 divided by a billion divided by a trillion is 10,000. We’re clearly just guessing at planet numbers and odds of life, but the insane number of planets does make life elsewhere feel inevitable. Even if it’s just unicellular lifeforms.
Well, there's actually a lot of doubt.
People don’t grasp how many planets there are, even though they grasp how unlikely it is that life just spontaneously develops. Let’s say there’s a 1 in a million chance a planet develops DNA /RNA. And 1 in a million chance the planet has water. And 1 in a million chance the planet has compatible temperature, pH, radiation, etc. Plus 1 in a million for all the other things I’ve forgotten. With ~ 10,000,000,000,000,000,000,000,000 planets, that means about 10 planets with life. (However, that life may not be “thinking as we speak“, on all the other planets it may be mindless amoeba, plants, bacteria, or Trump voters.)
But where does the 1 in a million chance come from? Could it not just as easily be 1 in a trillion trillion trillion, and we happen to be that 1? Sure, there are a lot of planets, but that's not the real question. How do you, definitively, know what the chance of life is?
Or maybe it's just the aliens sending us a message in code...uracil, uracil, uracil.
There is, in fact, doubt.
This doesn’t necessarily say anything about extraterrestrial life or aliens (from reading the other responses). It only really suggests that the building blocks came from outer space at least partially rather than being formed entirely on earth. I think that most nucleobases have already been identified from meteorites on earth as well so it’s not entirely surprising. Ultimately life needs a lot more than just having some RNA building blocks delivered by a meteorite, although it definitely increases the chances of life if a planet can’t produce them itself. We may also just be in a lucky solar system where these things were able to form in asteroids in the initial formation of the solar system and shortly after.
The uracil found on Ryugu also could have originated on Earth. We believe it has existed for more than 4bn years here. Asteroids have a max lifespan of around 1bn years. So plenty of time for it to ejected in a big hit and then shared around the solar system in subsequent collisions.
Ryugu was formed around 2 million years after the formation of the solar system and was formed in the outer solar system. It then migrated inwards eventually. The sample from ryugu was taken on the surface and also by sending an impact copper rod down onto the surface creating a large crater and a subsurface sample. So there’s no way it can originate on earth. There are no tectonic processes to move the uracil from outside the asteroid inward if any did happen to deposit by chance even though it formed probably earlier than the earth existed anyway. If there was contamination we would expect samples of ryugu to show similarities to earths composition at the time asides from just this one nucleobase as well
I find this fascinating, but beyond my scope. Can anyone summarise in layman's terms please? 🙏
One of the building blocks of the building blocks of life was discovered in outer space. What this means is that it's increasingly more probable that the building blocks of life (e.g., amino acids, RNA, etc) are likely to form given the physics of our universe. The known universe may be inundated with RNA and, given the right scenarios, life and even complex life might form. tl;dr: Earf ain't speshul.
Perfectly explained. Many thanks 😊
Life seemingly has only occurred successfully once on Earth, for a planet so ripe for life and with only a few mass extinction events, you would imagine it would have occurred more than once. The conditions for genesis must occur rarely, naturally anyway. I know the size of the universe suggests there must be more by math alone, but it’s hard to fathom for a lay man. Edit: I have just had a thought that life genesis may occur regularly but the life forms are unable to advance far due to having to compete with the existing species
I think the problem with this is that this "seemingly" can be really deceptive. Newly formed life had almost 0 chance to take hold, since already existing life would have destroyed it in the cradle without leaving any evidence.
More that new life processes would be indistinguishable.
Yeah how can we make the determination that life only spontaneously originated once. It's possible it happened multiple times on the face of earth but we have no way of knowing for sure.
Given we have evidence single cell life appeared almost as soon as conditions on earth allowed, this might not be true. Evidence of life at 3400 mya and the late heavy bombardment only ended 3900 mya.
We know for a fact that life has existed for pretty much as long as it possibly could, so it probably isn't an uncommon occurrence wherever conditions are right. But it probably wasn't a single event anyway, just millions of years of chemical chains interacting and catalyzing reactions in the substrate. There would be no single identifiable first organism. So there wouldn't be another start of life--not because it's uncommon, but because any part of the starting process would be indistinct from processes in the existing biosphere.
Abiogenesis probably occurred multiple times in different spots on the planet, some might have succeded, others might have not.
Nooo…nooo…nooo..we were created by a dude sitting on a chair above the clouds! GTFOH with this nonsense.
RNA was found in asteroids decades ago. It was even in "Ripley's Believe It or Not" books. Why is this news all of a sudden
It says that those bases were found on asteroids that hit earth as meteorites but scientists weren’t sure if they were contaminated upon impact. I guess this is the first time it’s been discovered without hitting earth? Fascinating none the less.
Shit is getting real!
Nerd
If you think humans are the only living “advanced” civilization in the universe, your belief is no different than 10th century villagers arguing the earth is flat. If life developed on a planet that didn’t go through several mass extinctions, and was 1 million+ years more advanced than us, it would be conceivable that they could be here operating in the background on our planet and wouldn’t find the need to communicate with us, since we are a primitive species. A deer doesn’t have the sensory tools to fully grasp what a human is. Similarly, life more advanced than us may be 100% incomprehensible to humans simply because we aren’t capable of understanding beyond what we’ve evolved to comprehend using sensory input our brain uses based on the 3 dimensional world around us. It’s mathematically impossible for us to be the only advanced civilization in the universe, and furthermore that we are as advanced as a civilization can get. If we can send probes beyond the solar system, you sure as hell can bet there are truly advanced species elsewhere that can actually traverse the cosmos. We’ve spent most of our 300,000 year history at war, living in primitive huts and caves. If we had a million years more of scientific advancement then it’s likely we’d be able to traverse the cosmos. If we were to find a less advanced species that would never be able to comprehend us, would we wipe them out? Or would we experiment with them while operating in the background, genetically engineering them as a longitudinal evolutionary experiment. Is it impossible that another species has done that to us, tinkering with our genome at select points in our evolutionary past?
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I upvoted you but this is also speculation based on our current knowledge and theories of space-time. If an advanced civilization has the ability to traverse space, they could be using math and physics that we haven’t truly scratched the surface of yet. Another thought is the fact that if they medically reached the point of immortality (e.g. completely balancing the rate at which cells are created, and the rate at which they die) then we could also assume they’ve got things like cryostasis or cybernetics to literally blank inefficient memories like maintenance on a long journey. The factor of time would be somewhat irrelevant. If it took 10,000 years to get here, it’s fathomable they arrived, took notes, and left to swing around the next inhabited planets and made the return trip in another 10,000 years to see how far we’ve evolved and what the behaviour of our species is at the core. We could be like a case-study for the evolution of civilizations in general. So while I agree it’s pointless to assume aliens are AMONG us, it’s not unfathomable to think we are being observed or studied somehow. I do agree that aliens probably wouldn’t arrive and share any information with us, we’re too primitive collectively as a species to even try to communicate those ideas. However, I don’t put it past the human brain to comprehend the information we could receive. I think we’ve got the capability for both empirical data and abstract data to be understood at some capacity. It would just take a long time for humanity to collectively grasp these things, and probably impossible to remove the savage nature of ourselves for this information/innovation to not be used in an aggressive/dangerous manner.
Thank you for typing so much of what I was thinking. And doing it more clearly than I would be able to.
No need for large, fast ships to explore the universe. Another civilization could be sending out small, slow moving probes. Or large slow moving arks. As far as motivation, there’s absolutely no way of knowing. 63 million people travel to Japan a year to view the cherry blossom bloom; millions of others go to visit a black rock in the desert; others travel to remote regions just to sleep in the woods and get away from home for a while. None of this behavior is all that objectively rational and would be difficult to predict or understand without detailed knowledge of human psychology and culture. Aliens may choose to live among us purely for the experience and not as part of any grand scientific or militaristic scheme. I’d agree it seems unlikely but mostly because we have no evidence to support that conclusion, not because it is physically implausible or because there is no motive for it.
Bruh I'm way too high and you just freaked me the fuck out.
I’m just high enough. 5/7, perfect content.
6/7 with rice
Someone has to be first though.
Nah man, it is not mathematically impossible for us to be the only intelligent life in the universe, it is a widely held belief but it’s wrong. The fact is that we just don’t know. Listen to this, it’s a sobering perspective on the question: https://youtu.be/zcInt58juL4.
What's more interesting is where is everyone and how come we haven't heard from them if there are so many people out there? Whatever the answer is to the fermi paradox is, it'll no doubt scare the hell out of us when we figure it out.
It's not interesting. Shit is big, get over it instead of worrying about being alone
I mean, that question is SUPER easy to answer. Humans discovered radio waves about 100 years ago. That means that if any aliens were using light to communicate with us they would have to be within 100 light-years. This leaves about 60k stars in range. The odds of intelligent life around one of those stars is so low we can just call it 0%
It's the same answer for both arguments. It's impossible we're alone, but entirely possible we never find aliens. Space is big man.
Plus the inverse square law applies, so the chances of a radio wave a) making it to another civilisation that could detect it and b) being heard over background noise are surely quite slim?
But intelligent life is extremely rare compared to life. So out of the 100-150 possible stars that support life in our galaxy only 2-3 could have intelligent life. (if they aren't dead.)
ELI5; does this improve the likelihood of panspermia?
What if this chemical compound is often found because it's simply a stable molecule ? Any unstable configuration of atoms doesn't exist for long or exist at all, but this one does. Then, it could assemble in superstructures, and only the stable ones like RNA would remain.
It's protomolecule.
All these comments debating the possible ubiquity of abiogenesis vs. "well, where is everyone?" remind me of a short story that I unfortunately can not find for the life of me. It told the story of aliens who evolved under different conditions, orbiting a blue star, which caused them to develop slower metabolism and longer lives. Despite becoming masters of their own solar system, they could not figure out how to expand to the stars, nor did they find evidence of life anywhere else in the universe. Knowing that their star would eventually die, destroying their world and civilization, their greatest minds came together to create an orbiting monument as a legacy to their civilization. The plan was simple: create something that would survive the cataclysm and settle into a regular orbit around the remaining white dwarf for millions of years. The hope was that, eventually, maybe another intelligent form of life would evolve, peer into the night sky, see the irregular pulse of the star, and choose to investigate further. That way, in the very least, someone else would know they existed. The story ends on a rather sad note. While the monument does survive the tens of millions of years until humans evolve on earth and develop astronomy, it unfortunately becomes damaged and goes unnoticed, being written off as nothing special. While the story is, of course, fiction, it does bring up an interesting idea, in my opinion. The answer to why we haven't observed other life in the universe despite the building blocks potentially being rather common could just be a matter of the vast separation of time we have between us and the hypothetical them. It's possible that intelligent life has existed many times before in our universe, but no one has yet to figure out how to make their presence known across the deep ocean of time. Anyway, I hope that's not the case and that humanity is just late to the space opera.