The early start life got on Earth, and the presence of extremophiles both suggest that simple life will emerge whenever possible and may be rather plentiful in space. The criteria for the emergence of complex life, however, are much tighter. That's why it took complex life another 3.5 billion years to appear after the bacteria evolved. Complex life is what is most fascinating about alien life because it is a prerequisite for intelligence and technology.
In fact, some more recent studies may or may not suggest that complex life appeared around 2 billion years ago. But it never evolved hard shells or anything more complex than jellyfish or worm like creatures, and it eventually went extinct. If this is true, (hard emphasis on IF) This would mean that even if complex life evolves, it is not guaranteed to suceed immediately.
I've read the proposal that hydrothermal seawater eutrophication may have triggered local macrobiological experimentation 2.1 BYA in the Francevillian sub-basin. The speculation is that the limited range of this congenial environment prevented life from getting a larger foothold, making it more vulnerable to extinction. But even after succeeding on a global scale, the five mass extinctions since the Cambrian and the sixth mass extinction now underway show that there is nothing guaranteed at all about complex life.
Or the early start life had on Earth was extraordinarily improbable and the chances of life beginning quickly enough to allow the time needed to develop complex life, let alone spacefaring life, is slim to none. With a sample size of one, we just don’t know.
Abiogenesis occurred within a few hundred years of the Earth's formation, probably in hydrothermal vents. This suggests that, given the right conditions, it is not an improbable event. Since chemosynthesis does not depend on light, the right conditions may occur in many non-Earth-like settings - for example, in the subsurface oceans of Europa and Enceladus.
@@fr57ujfinterestingly all these extinction events also potentially demonstrate that once life is "refined" by enough natural selection it's almost impossible to completely get rid of it.
Scientists: There used to be purple life on Earth! Laymen: So what happened to it? Scientists: Cyanobacteria killed it by producing toxic oxygen. But don't worry, there may be purple life on other planets! Cyanobacteria: “I sense something, a presence I’ve not felt since…”
The fact that most light from red dwarves (obviously) comes in the form of red and infrared oddly supports the idea of entire ecosystems with animals equipped with predator vision
And if there are species advanced enough they would have to wear protective suits or armor just to be able to stand in our sun's light if they decide to visit or invade, great idea!
There won't be any animals on a planet orbiting a red dwarf. There's more to make it worse, but can start and end with the habitable zone for a red dwarf star means a planet orbiting the red dwarf closer than Mercury orbits our sun. Ends up with no atmosphere, tidally locked aka the one side blazing hot while the other is staggeringly cold, also, red dwarfs are rather more active that G class stars like our sun so cue more of the ionizing radiation that is lethal to DNA/RNA (if it helps, recall those movies/shows with, that was equivalent to 30 chest x-rays). Lastly, let us assume animal life and a change in allele frequency over time aka evolution and so animals there would evolve to not radiate heat in the same fashion as animals on earth do. Or maybe animal life there would be limited to cold-blooded animals like our snakes, lizards, gators, crocs, etc. Oh, speaking of snakes, and infrared vision, have fun on your red dwarf planet chock full of pit vipers. In other words, what you are imagining, we already have now on earth.
@@mosquitobight Nice, do you know perhaps the species or nickname? TBH I'm most intrigued about the black blossoms. Overall there are a few "goth flowers" out there (including wild ones), but not too many. 🤭
we keep searching for life that is like us, but if life can exist in places on earth that humans could not tolerate, then why couldn't there be developed life that don't require the same conditions?
A good question, but the extremophiles are limited in how complex they can become. Because carbon is so capable of linking up with so many other elements in stable, useful forms, in so many different ways, it makes sense for any complex life to be carbon based. Silicon based life would almost certainly be more basic.
@@CaritasGothKaraoke When I read your comment, without the context, I thought of a planet where Cheesepuffs roamed wild, and, perhaps, were the dominant predator, rather than the prey they are here?
I have seen what looks like trilobites or isopods about an inch or inch and a half wide swimming happily in blood red sulphuric acid ponds and lakes on top of a Cu Zn mine tailings deposit. Could never find anybody else in the world who knows of this life form or variety..... Which is weird. If you work more than few days on a drill on this site, your clothes fall into pieces due to the acidic air on top of the pond.
That's interesting. 😮😎👍 It's indeed not guaranteed that scientists researching extremophile lifeforms already know about these. Have you considered catching a few with a net, together with a water sample (big jar, for longer chemical stability)? Hard to refute their existence with the jar in hand, and the species/family could be identified... or named after you, if new... 😁👍 I'd assume the isopods or whatever you saw, might be hardy enough to venture briefly into the toxic water for food like biofilms of extremophile bacteria, while not living in it constantly. So if you really decide to collect some, to increase the likelyhood for them to reach the scientist/university/lab alive, I'd recommend to put some of them in a dry jar. (Isopods are weird and primeval. There are isopod species that live on land as well as aquatic ones, the land-dwelling ones basically are breathing with modified gills. They are closer related to lobsters and crabs, than to insects.) I'd compare their implied lifestyle with that of eels diving into brine pools at the bottom of the oceans. If they stay even seconds too long, they get a toxic shock... saw that in a video filmed by a science probe.
You should really try to get this information to individuals who research Extremophiles. There is still so much more that can be learned and discovered in this unique category of biology and science as a whole. Just a guess but those isopods probably developed a symbiotic relationship with specific bacteria that allows them to pull nutrients from these extreme environments. Then overtime they keep adapting to better endure such extreme environments such as the one you described..
@@tesseract_1982 unfortunately... I had nothing like a glass jar to put them into when I was watching them... Would have been easy to catch them too.... When I returned a year or so later to catch a few.... The damn environmentalists had covered the place in earth and grown grass over the site.... I have seen plenty of identical sulfuric acid tailings pond before then.... But never with any life forms visible.... I wrote to many biologists afterward about these" trilobites". Even researched how acidic the first oceans may been.... Wondered if first trilobites might have lived in similar acid conditions... Maybe first species never got preserved??? Not many sedimentary rocks of that age in the world.... I have seen a lot of weird things as a field geologist exploring older formations.... But the living "trilobites" were very puzzling... I could never find any species of Isopods who looked as squat and chitinous as these ones.... And they all seemed to be fresh water species.... I'm not a biologist though nor any kind of isopods expert. It was very unlikely that freshwater tough isopods wandered into these toxic waters from any nearby fresh waters though.... The ponds were at higher elevations than any freshwater sources.... And drained downward... Rain would have been only source of dilution.... Also there are many beautiful clear ponds and lakes that are located ober rock formations than contain enough sulfides in the rock to create mildly acidic waters that harbour zero aquatic life.... Still great tasting drinking water though! (hope it never hurt my health) and not even bugs or mosquitoes hang around these areas for some reason... No fish... But I never studied or looked too hard at the biology here... There is a big difference between ruby red sulfuric acid liquids (mixed with H20) and clear limpid acidic waters that taste great.
@@benmcreynolds8581 that makes a lot of sense.... These creatures had to be anaerobic and also very complex and evolved. Maybe people need to start exploring more non-rehabilitated tailings sites... But the mines are not more than a century old..... So where did the isopods or whatever come from or evolve from so quickly... Maybe you are right.... Extraterrestrial colonies??
Thank you for providing a link to an open-access paper. The public must demand that all publicly funded research is published open access. If this means that authors and their institutions must pay thousands of dollars for each publication, then so be it. This will encourage more interdisciplinary collaboration and more research participation from undergraduate students. More coauthors implies more cost sharing for risky theoretical projects that are unlikely to receive funding.
Or we just ban JSTOR and make whatever insignificant costs to run it, a public database the public can access. We need to do this with all Case Law as well. Its criminal to require a defendent to hand over money in order to access case law. This only makes sense. And it IS NOT expensive to maintain a website with access. Now if there's proprietary research then thats different. But JSTOR doesn't ever pay Accademic Paper Authors lol.
Thinking aloud: if they allow AI companies to train on copyrighted material, surely they should also be training on 'all of science'. AKA every published paper. otherwise, what's the point, this data mining is how they will train it to first principles, and then make discoveries. In other words, that info is already out there and ready to be shared. Selfish AI companies need to be regulated and made to share.
Our version of life has its sweet spot using a specific chemistry within a narrow range of temperature and pressure. But we don't know very much about how permutations of those parameters ultimately favor or hinder the development of other kinds of life. Are there other collections of chemical that will undergo abiogenesis in different environments? Could there be cold life on ice moons, metabolizing and reproducing super slowly over thousands and millions of years? Or as one scifi author put forth decades ago, could there be super fast life existing on the surface of neutron stars?
In many ways water is a surprising solvent for life. Liquid Methane, Ethane, or other organic liquids feel more promising. In the ocean mid-points where volcanoes supply sulfur, bacteria using sulfur supply complex life such as crabs, worms, and other complex life.
@@rocksnot952 Triton is a candidate for methane/ethane based life. Bacteria using Arsenic, viable due to the low temperatures, have a projected signature which is consistent with values found from some Triton lakes. Until a sample, kept cold for analysis, is needed to determine whether the suspected life is real.
@@rocksnot952 At the moment the spectral evidence from the moons of Jupiter and Saturn strongly suggests life, both water based, from volcano steam emissions, and methane/ethane based from Triton lakes. Until sampling missions have been made, no definitive statement can be made. If an Exoplanet had such light emission lines, it would be assumed to be caused by a life form.
The reasons for Chlorophyll's light absorbtion spectrum are rather interesting There are other forms of primitive life on earth that absorb green (blue/green "algae") and early earth oceans were likely to have been full of them - meaning chorophyll probably evolved to absorb what was available at depths sufficient to block UV penetration On a more terrestrial note, there are some experiemnts to try and tweak chlorophyll into absorbing a wider spectrum of light - which would result in BLACK plants
Modern Humans: about 300,000yrs on earth Photography: 2k yrs max... MAX... 🤷 if there's life in our own solar system, we lack the ability to detect it atm, much less lightyears away!
Great content but, (and it's probably just me) being spoken to like I'm a kindergarten child grates on my nerves after a while. Some museum tours do this too. I think this is the first time on this channel I couldn't watch till the end. I'll probably get flamed but I thought Ben should have the feedback just in case it's not just me.
Yup. I have also noticed a lot of popular content about science in English talks to people like they never learned anything after mid school. Including books. More intellectually challenging content is more rare. P.S.: And most thing explaining photosynthesis simplify it so much that information becomes inaccurate. Like equating type of photosynthesis to colour of cells. There are greeen sulfur and non-sulfur anoxygenic photosynthetic bacteria, there are also many cyanobacteria which look purple due to lots of phycoerythrin, same with red algae. Also, colour depends on the exact proportions of numerous pigments they have, and that depends on lighting conditions, so the same culture changes colour under different conditions! So that is the topic I know. Over-simplifying it can give people false ideas. Maybe the same is true with other topics as well.
That was pretty painful. I understand the need to simplify information for the layperson but I don't think describing things like you're talking to a toddler is necessary. They took 5 minutes to describe what you said in 30 seconds. I also don't think "We've been looking for green ALL THIS TIME." is fully accurate. We've only been observing reflected light from exoplanets since the mid-2000s and I find it hard to believe everyone was only looking for green. This looked like a political ad for these two ladies. Full of spin. I wouldn't have said anything if it wasn't so grating... to just me of course. But maybe others.
Would you design a car with 5 wheels, would you design a plane without wings. Why do things keep evolving into crabs. Fact is, aliens would probably look vaguely similar to life on earth, there's certain evolutionary maximums that just work
But aren't red dwarfs a lot more active, and therefore more more dangerous? Or could there be some mechanism that can protect a planet from the extra flares they put out? And what can prevent a planet from being tidally locked since the habitability zone around red dwarfs needs to be so close?
I remember a astrophysicist saying we dont think certain stars (forgot which one) are capable of creating a goldi lox zone for an earth like planet. but in reality it is possible if the planet had a thicker atmosphere with something like sulphur to trap in cold/heat. ironically, many alien encounter stories mention they smell like sulphur. but if we're ignoring those certain stars, theres potentially a massive amount of potential worlds that we've been ignoring the whole time. i wish i could find where i originally heard that statement...
This is the exact thing I've been thinking. I was always wondering why are scientist always assuming life will need water to survive while it can have totally different structure.
Short answer: because you need a solvent for life’s chemistry and water is a very good one. Longer answer: Because water is such an effective solvent for a wide range of compounds and because you need a liquid solvent to do chemistry at low temperatures. Water has an unusually wide range of temperatures and pressures it is liquid. This is promoted by solid water being less dense than liquid, allowing insulating cover of solid (ice) over liquid (water) keeping bodies of water from rapidly freezing solid. It has a high capacity to hold heat, so it smooths out extreme environmental temperature shifts. And it has strong surface tension which is important in the transition to life on land, among other things. And it is critical to the one example of life that we know about.
Once you solve immortality, whether we are immortal or the alien extraterrestrials are in mortal than time travel distance that light your speed isn’t such a problem. There are some projection videos that say by the year 2100 we may have the ability to bioengineer ourselves to become immortal. So then Traveling 30,000 light years isn’t that big of a problem to go on vacation
As per Jack Cohen and Ian Stewart's "Evolving the Alien: The Science of Extraterrestrial Life" [2002]? - the book originating with a lecture that Cohen had revised over many years, which he called POLOOP, for "Possibility of Life on Other Planets".
0:37 What about the other reason we haven’t found alien life? This being that it is extremely rare in the universe, but this does not mean that earth is unique. The cosmos looks rather hostile out from under earths warm but perilously thin atmosphere.
On the other hand, the opposite is true for red dwarf stars. So they have a lot more time than Earth to evolve complex life. So even if complex life needs much more time to evolve under those conditions - it has that time.
@@KaiHenningsenyeah but all of our energy comes from the sun, so if the star isnt giving the planet enough energy then complex life wouldnt have enough energy to evolve
@@Scotty-vs4lf - In a simple way life does not need energy to evolve. All that life needs is energy to survive and multiply. The ones that do this better will be around for the longer term and evolution is the passive (no extra energy needed) result. What isn't discussed is how to determine the minimum energy needed for complicated life forms. Specifically is there an energy saving in being a multicellular wolf on Wall Street life form versus just remaining the best possible microbe under the red dwarf.
@@pendarischneider yeah evolution doesnt require energy (well any more than is needed for survival to begin with) the problem i was thinking about was that complex life forms inherently need more energy for larger brains, and bodies that are useful to actually do something complex. if a worm had 10000 iq i still wouldnt consider it complex cuz all it can do is slither around
A terrific video, Dr. Ben! Lots of great interpretation by you to explain some otherwise complex principles, with lots of relevant "b-roll" and the occasional cute clip. I recently read Dr. Kaltenegger's enjoyable book, so it's very nice to see her and her colleague talking about the challenges and what we should actually be looking for. Personally, I suspect the universe is full of planets hosting bacteria, and maybe a few with complex life, but highly doubtful we'll find technologically advanced life -- even here on earth, advanced life (radio waves, etc) only accounts for 3*10[-6] % of our planet's existence! Don't blink, ETs, you might miss us!
I learned this was just a bunch of theories without any evidence to back even one of the suppositions. Also, I doubt that is the worlds leading expert in that field.
I am sceptical... There are many well-studied indications that Life as we know it, really is as niche and special as we find it to be. For instance, there's at least one study that shows that red dwarf M-class stars could be detrimental to the evolution of complex life. These stars generate too little ultraviolet for photolysis of carbon monoxide, making atmospheres toxic to oxygen-breathers. And oxygen of sufficient levels is what made the Cambrian Explosion possible. Also, there are good reasons to deduce that green plants have an edge over other photosynthesizers in our Sun's light. Microbial life may be everywhere, but complex life with potential sapience may limited to Earth analogues around a yellow dwarf star with a moon and plate tectonics.
I see two problems to be solved in the search for Life: 1. Life is based on Physics and Biochemistry. Any life still has to conform to basic natural laws, and thus is limited to be physically possible. Hence Life does not differ in principle to non-life places. 2. Life evolves and thus with time will use all available resources. It also means that with time, it will use all possible energy gaps, making its detection more complicated. On Earth for instance, the current oxygen levels are not the highest anymore. It's possible that Earth in the future will have even lower oxygen levels, because later iterations of complex Life will be even more efficient breathing oxygen and thus can cope with increasingly lower oxygen levels.
Thank you, great episode. I bought a couple of Nick Lane books, and Alien Earths will make a great counterpoint! Edit: folks if you don't know Nick Lane, professor of evolutionary biochemistry at UCL, look up his lectures right here on YT. You'll get a lot more out of it if you have some college level biochemistry to start with, but not crucial.
We haven't even seen the actual surface of any exoplanet and yet we are asking "Why is alien life so hard to find?" How about we wait until we actually start looking. We've barely begun to look. It's like Columbus taking a little boat a few hundred metres off the shore and saying "Sheesh, what does someone have to do to find India?"
Isn’t the main issue with planets in the habitable zone of red dwarf stars is that they would have to be too close to the star and be exposed to too much of its radiation? And also too close to its gravity well and possibly be tidally locked to the star? And that solar flares from the star would happen too frequently to allow life to gain a foothold there?
The main problem is space weather. Star wind, outbursts of plasma from Red Dwarfs. A Neptune planet in the Goldilocks zone with just sufficient atmosphere would be a potential life source. Sufficient atmosphere for the Star wind to blast away enough atmosphere to leave a thin trace, similar to the Earth's atmosphere in density after the Star's youth. Red Dwarfs initially have very active space weather which reduces as the star ages. If the active phase leaves a planet with a thin atmosphere, and a star stable enough for a stable atmosphere, there is no reason life wouldn't develop. (A thin atmosphere is needed for photosynthesis, light has to be able to penetrate. ) Tidal locking while awkward, does not preclude life. A Neptune type planet, with a radius bigger than earth, would have a lit area as great, or greater than, as earth's land area. Tidal locking has the advantage, the lit area would be lit continuously
Transit method of detection tends to find large gas giants and super earths around red dwarfs where chance of life like ours is already low. We need more sensitive methods to detect rockier earth like planets around G type stars to find life that may look more similar to what we have on earth. So current sample size is going to favor infrared life because we were not good enough yet at detecting planets that would harbor life in the visible spectrum
The color may be different but those microbial ecosystems are biofilms, aka slime. And that’s the way life on earth existed for most of the time life has been here. For all the speculation on what form alien life might take, we already know what most alien life will look like, at least to our eyes: slime on rocks.
Stars and planets made from the dust of larger supernovae would potentially have stable isotopes of heavier elements than we do. I wonder how that might factor in.
0:33 only place we found life... Umm how many other places we been? When did we make interstellar travel? Or even just a camera capable of capturing any information about the inner atmosphere...
Did you not watch the video? He explains very clearly how we currently hunt for life on planets, moons and exoplanets. We haven't found the spectrum signatures yet that match the signatures here on Earth. So yes, Earth is the only place we have found life. And yes, we have also travelled to other planets and moons and taken and analyzed samples. Only a handful, but you don't seem to understand how the hunt is done. It's primitive, but we have looked at over 5000 planets.
@@High-Tech-Geek No 33 secs in and at that point idiotic obvious but not helpful statements were made. Phrasing was also intentionally done in opposition to life existing. Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space. - Douglas Adams. It's like closing your eyes and saying you can't find single celled organisms. First of all you probably won't see most single cell organisms with your eyes open... Much less with them closed. The rest of the video just goes on to say the same. We don't have the technology yet. Got a few general ideas.... And sure we are looking but we don't have the tools yet. Saying we haven't found life is like saying the chicken is cooked as you watch it lay an egg. It ain't even prepped to cook...
@@limsalalafells I understand what you're saying, but spectroscopy analysis is pretty cool. It can tell us the composition of the atmospheres around these 5000+ planets. Imagine if we find oxygen and methane gases in the same proportions as here on Earth? That would be a good indicator of life. It wouldn't confirm it, but it would be a great sign. But the lack of seeing these elements so far in the right proportions and on the right type of planet speaks volumes. We haven't found these proportions yet. But the whole point of this video is to say that maybe life on another planet doesn't emit the same gases that life on Earth does. So they are looking for other combinations of gases. Very cool stuff.
@@High-Tech-Geek all great, bad intro. If I start a conversation by saying your worthless and will never do as well as your great grandfather. Explain his achievements loses some of it's meaning to you. If instead I start by saying you've got a lot to strive for, or you got potential.... It puts the story about your great grampa in a whole different light. While you still may not live up to the same standards you at least aren't being knocked down before you have a shot.
As a child I was always annoyed as to why they always thought that alien life would resemble our form of biology...thankfully they are shifting their thoughts process
Based on the countless Star Trek and other space movies I have seen; most aliens look amazingly like humans. Also, outside of our immediate solar system, most planets / moons not only have a climate suitable for humans to be on without a protective suit, but also have breathable air. We are unfortunate enough to only have one planet, Earth, that meets those criteria. Even more amazing, the majority of these planets also speak very passable English.
why isn't anyone talking about K class stars? why are they always forgotten. they are better than M-class stars. and there are more than sun-sized stars.
The most likely way intelligent life will be surprising is an equivalent to an elephant. Human life nearly disappeared 900,000 years ago due to a deep ice age period. If the earth was slighter colder, elephants would be the dominant life form. Elephants have been shown to use names for individuals, and they are capable of communicating via the ground using infra sound frequencies, allowing them to talk to each other when they are seemly apart.
It might be that life manages to evolve on a planet around a bright star where the planet was slowly spiralling in, but, somehow, perhaps due to the gravity of gas giants in the system, gains a more stable orbit. It's an unlikely scenario, but with an estimated 10 to the power of 24 planets in our observable Universe, not quite as unlikely as it first seems.
No lie I thought scientist or biologist looking for life already took this into account, I didn't know this was a revolutionary idea, like even a video game like No man sky predicted this
700 nm is NOT the Far-Infrared! 700nm is barely into the Near-Infrared. That’s why it’s called the Red Edge and not the Far-Infrared Edge! FIR is more like 100,000 nm! Sigh…
If the oxygen crisis didn’t happen and kill the purple bacteria, then the purple bacteria would have evolved into purple trees and purple people, and even purple chickens. Our world would look a lot more like the majority of other planets hosting life right now
It never ceases to amaze me the arrogance of commentors who use the blanket term "scientists" without being able to name a single one who thinks they understand all the parameters constraining the formation of life.
FWIW I suspect that simple life will be very common in the universe but intelligent life will be very rare as the hurdles to evolving higher organisms are very high. The only alternative to that is that life on Earth was a completely statistical freak and we are unique in the universe. Somehow that feels unlikely to me but your guess is as good as mine.
No mention of alternate forms beyond carbon based life. Maybe a follow-up that goes back a stage to chemistry and discusses which elements could be built into chains (e.g. silanes) would be good.
Nitrogen compounds under huge huge pressures can have interesting chemistry. Also, other liquid apart from water can be used. Some bacteria even on Earth live in liquid CO2 lakes on the ocean floor.
@@KateeAngel I assume you're talking about Qian et al., 2016 Nature paper ("Diverse Chemistry of Stable Hydronitrogens, and Implications for Planetary and Materials Sciences"). I wasn't aware of this paper. It demonstrates nitrogen can form very long chains under pressures over 36GPa (about 5.22 million psi). This conditions do exist deep inside gas giants. But one problem jumped out at me and did not escape the author's notice either. As they say "Nitrogen-based life could be possible, but the likelihood of this is highly limited due to high temperatures in these planets’ interiors, which could make lifetimes of metastable compounds too short." Use of a liquid other than water seems far more likely than silicon or nitrogen based life. Water just has a combination of many chemical and physical properties useful for life, but those are not unique to it. Even so, living in a liquid is not the same as having biochemistry based in that liquid. The bacteria living in or at the edge of undersea lakes of CO2 still use water as their intracellular biochemical solvent, not liquid CO2.
Hey, I'm signed up for notifications, but I see notification for all the other youtube channel stuff but no video. How do I fix this so I don't visit for shorts or other stuff
It’s a big universe. Odds are there is a species that looks like Greys out there. Or maybe it’s an infinite universe, which means there are an infinite number of species that look like Greys.
Getting away from Chlorophyll is one step. Getting away from water is another. Getting away from STP is another ("standard temperature & pressure") Life doesn't even need to be molecular....or even atomic. There could be sentient plasma ("elementals") based life forms on the sun and we'd have no idea what we were looking at.
the way she talks is super-annoying and offensive: as if she thought that she is speaking to toddlers. which probably is true: she probably does perceive any laypeople as dumb toddlers. I appreciate her scientific knowledge, but it can’t justify such an astonishing level if arrogance.
I'm glad you adressed the fact that life might look entirely different on an alien world. Whenever there is a show saying that we're looking for oxygen and water I immediately discard the study because they are too narrow minded to ever find life.
If any one of those purple planets is in some early stage of life, by the times their light reaches us, they could have already evolved complex green life and the stuff that goes with it, like intelligent life. That life might have already invented faster than light travel, and be headed toward us, looking for a Planet B of their own
0:36 We're minuscule, while the Universe is incomprehensibly ginormous and unfathomably old. _THAT_ could be why we've not found extraterrestrial life. And if I wanted to watch a music video, I'd watch a music video.
I noticed two things that conflicted with what I thought I knew about sunlight. If I'm wrong, I'd be grateful for some details to correct me. First, if green plants are reflecting infrared, wouldn't that imply that they don't absorb heat? My understanding is that infrared isn't just the wavelength of a color our eyes don't register, it's the wavelength of heat itself. Either I'm wrong (totally likely) or I just never noticed that green plants don't get warm. Second, I'd heard that our Sun is actually a white color, tinted imperceptibly green, and that the yellow is due to the effect of the Earth's atmosphere. I can understand if chlorophyl based life adapted to the color of the light that gets through the atmosphere, and it seemed weird to me that chlorophyl would reflect the most abundant color of light, so are we sure what color the sun is? The rest of it is fascinating. Looking for the color of the gases that might have been metabolized by living organisms when the planet occludes its sun, then looking for the color of the reflection of those organisms' actual surfaces based on what their environment might encourage them to have. It's amazing what you can at least guess at from a distance you couldn't possibly travel with current technology.
We know that dark matter exists, we infer its existence as we can see its effects on the universe, we just don't know what it is. For example, people knew things fell to earth before Newton described gravity.
@@fractalwalrus5409 Exactly. Straw-man. Granted, you started with "we infer", in the subsequent argument you baked the conclusion into the premise. The observation is true, the cause however is speculative.... and Scientists conclude "dark matter" cause they dont want to entertain maybe they just dont have the full picture on physics. It's equally valid to conclude there's more physics out there we havent discovered yet. The idea there exists some weird form of un-observable/un-detectable matter is the science version of Jesus.
The early start life got on Earth, and the presence of extremophiles both suggest that simple life will emerge whenever possible and may be rather plentiful in space. The criteria for the emergence of complex life, however, are much tighter. That's why it took complex life another 3.5 billion years to appear after the bacteria evolved. Complex life is what is most fascinating about alien life because it is a prerequisite for intelligence and technology.
In fact, some more recent studies may or may not suggest that complex life appeared around 2 billion years ago. But it never evolved hard shells or anything more complex than jellyfish or worm like creatures, and it eventually went extinct.
If this is true, (hard emphasis on IF)
This would mean that even if complex life evolves, it is not guaranteed to suceed immediately.
I've read the proposal that hydrothermal seawater eutrophication may have triggered local macrobiological experimentation 2.1 BYA in the Francevillian sub-basin. The speculation is that the limited range of this congenial environment prevented life from getting a larger foothold, making it more vulnerable to extinction. But even after succeeding on a global scale, the five mass extinctions since the Cambrian and the sixth mass extinction now underway show that there is nothing guaranteed at all about complex life.
Or the early start life had on Earth was extraordinarily improbable and the chances of life beginning quickly enough to allow the time needed to develop complex life, let alone spacefaring life, is slim to none. With a sample size of one, we just don’t know.
Abiogenesis occurred within a few hundred years of the Earth's formation, probably in hydrothermal vents. This suggests that, given the right conditions, it is not an improbable event. Since chemosynthesis does not depend on light, the right conditions may occur in many non-Earth-like settings - for example, in the subsurface oceans of Europa and Enceladus.
@@fr57ujfinterestingly all these extinction events also potentially demonstrate that once life is "refined" by enough natural selection it's almost impossible to completely get rid of it.
It's life, Jim, but not as we know it
WouterVerbruggen
Yes, but who will teach them about love?
🖖
I'm a DOCTOR, not a bricklayer!
@@kellyrobinson1780 devil in the dark
In a pig's eye it is!!!
Scientists: There used to be purple life on Earth!
Laymen: So what happened to it?
Scientists: Cyanobacteria killed it by producing toxic oxygen. But don't worry, there may be purple life on other planets!
Cyanobacteria: “I sense something, a presence I’ve not felt since…”
The fact that most light from red dwarves (obviously) comes in the form of red and infrared oddly supports the idea of entire ecosystems with animals equipped with predator vision
They may have Predator vision, but they're skin may not be adapted to handle the UV rays. They may get third degree sunburns within minutes!
And if there are species advanced enough they would have to wear protective suits or armor just to be able to stand in our sun's light if they decide to visit or invade, great idea!
There won't be any animals on a planet orbiting a red dwarf. There's more to make it worse, but can start and end with the habitable zone for a red dwarf star means a planet orbiting the red dwarf closer than Mercury orbits our sun. Ends up with no atmosphere, tidally locked aka the one side blazing hot while the other is staggeringly cold, also, red dwarfs are rather more active that G class stars like our sun so cue more of the ionizing radiation that is lethal to DNA/RNA (if it helps, recall those movies/shows with, that was equivalent to 30 chest x-rays).
Lastly, let us assume animal life and a change in allele frequency over time aka evolution and so animals there would evolve to not radiate heat in the same fashion as animals on earth do. Or maybe animal life there would be limited to cold-blooded animals like our snakes, lizards, gators, crocs, etc.
Oh, speaking of snakes, and infrared vision, have fun on your red dwarf planet chock full of pit vipers. In other words, what you are imagining, we already have now on earth.
Predator world would be scary
I'm rooting for black plants and purple oceans, because that'd be hella goth. 😅 💜🖤💜🖤
Agreed
trying to see anything would be so ass without infrared binoculars
I watched a science video a few years ago that said a planet rained diamonds. Idk the legitimacy
There are pitch black bushes with black leaves, stems, flowers and berries growing right in the English garden of my city park.
@@mosquitobight Nice, do you know perhaps the species or nickname? TBH I'm most intrigued about the black blossoms. Overall there are a few "goth flowers" out there (including wild ones), but not too many. 🤭
Lisa speaks about this subject with such joy and passion. It's enchanting.
Both of the interviewees did such a great job communicating their excitement.
She speaks like everyone is in the third grade, though.
You mispelled annoying
@@ohsweetmystery i couldn't handle more than 10 minutes of this video because of it
I could listen to her all night 😚
we keep searching for life that is like us, but if life can exist in places on earth that humans could not tolerate, then why couldn't there be developed life that don't require the same conditions?
A good question, but the extremophiles are limited in how complex they can become.
Because carbon is so capable of linking up with so many other elements in stable, useful forms, in so many different ways, it makes sense for any complex life to be carbon based. Silicon based life would almost certainly be more basic.
I think when we say “like us” that often includes animals that can exist in places humans cant
Why just animals, Cheesepuff?
@@CaritasGothKaraoke When I read your comment, without the context, I thought of a planet where Cheesepuffs roamed wild, and, perhaps, were the dominant predator, rather than the prey they are here?
I've been wondering this too
I have seen what looks like trilobites or isopods about an inch or inch and a half wide swimming happily in blood red sulphuric acid ponds and lakes on top of a Cu Zn mine tailings deposit. Could never find anybody else in the world who knows of this life form or variety..... Which is weird. If you work more than few days on a drill on this site, your clothes fall into pieces due to the acidic air on top of the pond.
That's interesting. 😮😎👍 It's indeed not guaranteed that scientists researching extremophile lifeforms already know about these. Have you considered catching a few with a net, together with a water sample (big jar, for longer chemical stability)? Hard to refute their existence with the jar in hand, and the species/family could be identified... or named after you, if new... 😁👍
I'd assume the isopods or whatever you saw, might be hardy enough to venture briefly into the toxic water for food like biofilms of extremophile bacteria, while not living in it constantly. So if you really decide to collect some, to increase the likelyhood for them to reach the scientist/university/lab alive, I'd recommend to put some of them in a dry jar. (Isopods are weird and primeval. There are isopod species that live on land as well as aquatic ones, the land-dwelling ones basically are breathing with modified gills. They are closer related to lobsters and crabs, than to insects.)
I'd compare their implied lifestyle with that of eels diving into brine pools at the bottom of the oceans. If they stay even seconds too long, they get a toxic shock... saw that in a video filmed by a science probe.
You should really try to get this information to individuals who research Extremophiles. There is still so much more that can be learned and discovered in this unique category of biology and science as a whole. Just a guess but those isopods probably developed a symbiotic relationship with specific bacteria that allows them to pull nutrients from these extreme environments. Then overtime they keep adapting to better endure such extreme environments such as the one you described..
@@tesseract_1982 unfortunately... I had nothing like a glass jar to put them into when I was watching them... Would have been easy to catch them too.... When I returned a year or so later to catch a few.... The damn environmentalists had covered the place in earth and grown grass over the site.... I have seen plenty of identical sulfuric acid tailings pond before then.... But never with any life forms visible.... I wrote to many biologists afterward about these" trilobites". Even researched how acidic the first oceans may been.... Wondered if first trilobites might have lived in similar acid conditions... Maybe first species never got preserved??? Not many sedimentary rocks of that age in the world.... I have seen a lot of weird things as a field geologist exploring older formations.... But the living "trilobites" were very puzzling... I could never find any species of Isopods who looked as squat and chitinous as these ones.... And they all seemed to be fresh water species.... I'm not a biologist though nor any kind of isopods expert. It was very unlikely that freshwater tough isopods wandered into these toxic waters from any nearby fresh waters though.... The ponds were at higher elevations than any freshwater sources.... And drained downward... Rain would have been only source of dilution.... Also there are many beautiful clear ponds and lakes that are located ober rock formations than contain enough sulfides in the rock to create mildly acidic waters that harbour zero aquatic life.... Still great tasting drinking water though! (hope it never hurt my health) and not even bugs or mosquitoes hang around these areas for some reason... No fish... But I never studied or looked too hard at the biology here... There is a big difference between ruby red sulfuric acid liquids (mixed with H20) and clear limpid acidic waters that taste great.
@@benmcreynolds8581 that makes a lot of sense.... These creatures had to be anaerobic and also very complex and evolved. Maybe people need to start exploring more non-rehabilitated tailings sites... But the mines are not more than a century old..... So where did the isopods or whatever come from or evolve from so quickly...
Maybe you are right.... Extraterrestrial colonies??
@@sstorm1328 where was this? What country/ state/ city/ street/ coordinates/ etc?
If you are searching for alien life look no further than the back of my refrigerator..
This reminds me of one specific episode from Cowboy Bebop where the crew struggles with exactly this problem 🙂
"O God, I could be bounded in a nutshell, and count myself a king of infinite space-were it not that I have bad dreams". (Hamlet)
Thank you for providing a link to an open-access paper. The public must demand that all publicly funded research is published open access.
If this means that authors and their institutions must pay thousands of dollars for each publication, then so be it. This will encourage more interdisciplinary collaboration and more research participation from undergraduate students.
More coauthors implies more cost sharing for risky theoretical projects that are unlikely to receive funding.
Multiple authors don't pitch in to cover papers costs.
Hear, hear.
Or we just ban JSTOR and make whatever insignificant costs to run it, a public database the public can access.
We need to do this with all Case Law as well. Its criminal to require a defendent to hand over money in order to access case law.
This only makes sense.
And it IS NOT expensive to maintain a website with access. Now if there's proprietary research then thats different. But JSTOR doesn't ever pay Accademic Paper Authors lol.
@@SarunasZukauskas If it's unfunded research, not contributing to publication costs will weigh on their conscience.
Thinking aloud: if they allow AI companies to train on copyrighted material, surely they should also be training on 'all of science'. AKA every published paper. otherwise, what's the point, this data mining is how they will train it to first principles, and then make discoveries. In other words, that info is already out there and ready to be shared. Selfish AI companies need to be regulated and made to share.
Our version of life has its sweet spot using a specific chemistry within a narrow range of temperature and pressure. But we don't know very much about how permutations of those parameters ultimately favor or hinder the development of other kinds of life. Are there other collections of chemical that will undergo abiogenesis in different environments? Could there be cold life on ice moons, metabolizing and reproducing super slowly over thousands and millions of years? Or as one scifi author put forth decades ago, could there be super fast life existing on the surface of neutron stars?
Jupiter has immense pressures : the atmosphere components could act as solvents at temperatures similar to earth.
I'd be really surprised to find life that doesn't use water. It's the closest thing to a universal solvent that exists.
In many ways water is a surprising solvent for life. Liquid Methane, Ethane, or other organic liquids feel more promising. In the ocean mid-points where volcanoes supply sulfur, bacteria using sulfur supply complex life such as crabs, worms, and other complex life.
@@michaeledwards2251 Yes, but we haven't yet found life that doesn't require water in some way.
@@rocksnot952
Triton is a candidate for methane/ethane based life. Bacteria using Arsenic, viable due to the low temperatures, have a projected signature which is consistent with values found from some Triton lakes. Until a sample, kept cold for analysis, is needed to determine whether the suspected life is real.
@@michaeledwards2251 Well, have to go with the science. I hope they do find something like that. I just doubt it.
@@rocksnot952
At the moment the spectral evidence from the moons of Jupiter and Saturn strongly suggests life, both water based, from volcano steam emissions, and methane/ethane based from Triton lakes.
Until sampling missions have been made, no definitive statement can be made. If an Exoplanet had such light emission lines, it would be assumed to be caused by a life form.
The reasons for Chlorophyll's light absorbtion spectrum are rather interesting
There are other forms of primitive life on earth that absorb green (blue/green "algae") and early earth oceans were likely to have been full of them - meaning chorophyll probably evolved to absorb what was available at depths sufficient to block UV penetration
On a more terrestrial note, there are some experiemnts to try and tweak chlorophyll into absorbing a wider spectrum of light - which would result in BLACK plants
Modern Humans: about 300,000yrs on earth
Photography: 2k yrs max... MAX... 🤷 if there's life in our own solar system, we lack the ability to detect it atm, much less lightyears away!
Why do scientists speak to the camera like we're about to have our ankles broken for moving a model penguin...
Great content but, (and it's probably just me) being spoken to like I'm a kindergarten child grates on my nerves after a while. Some museum tours do this too. I think this is the first time on this channel I couldn't watch till the end.
I'll probably get flamed but I thought Ben should have the feedback just in case it's not just me.
It's not just you
Yup. I have also noticed a lot of popular content about science in English talks to people like they never learned anything after mid school. Including books. More intellectually challenging content is more rare.
P.S.: And most thing explaining photosynthesis simplify it so much that information becomes inaccurate. Like equating type of photosynthesis to colour of cells. There are greeen sulfur and non-sulfur anoxygenic photosynthetic bacteria, there are also many cyanobacteria which look purple due to lots of phycoerythrin, same with red algae. Also, colour depends on the exact proportions of numerous pigments they have, and that depends on lighting conditions, so the same culture changes colour under different conditions!
So that is the topic I know. Over-simplifying it can give people false ideas. Maybe the same is true with other topics as well.
You are not alone, brother
This was super interesting! Thanks for posting it.
I love how excited the young woman is about her work. Nerds nerding out is awesome.
Just discovered this channel... Amazing content! Congrats 👏🏽
Make a 1 hour compilation for us to fall asleep to!!
I love your channel
I love women speaking to me like I'm an idiot.
7:41 that angle makes me feel like a baby in the cradle listening to sci fi stuff instead of a lullaby
A Decade in Blue (Da Ba Dee) - eiffel65
"I'm Blue If I Was Green I Would Die, I'm Indeed I Will Die, If I Was Green I Would Die.."
That was pretty painful. I understand the need to simplify information for the layperson but I don't think describing things like you're talking to a toddler is necessary. They took 5 minutes to describe what you said in 30 seconds. I also don't think "We've been looking for green ALL THIS TIME." is fully accurate. We've only been observing reflected light from exoplanets since the mid-2000s and I find it hard to believe everyone was only looking for green. This looked like a political ad for these two ladies. Full of spin. I wouldn't have said anything if it wasn't so grating... to just me of course. But maybe others.
@6:35 it's not FAR infrared. It's NEAR INFRARED (NIR). Anyways good video!
Would you design a car with 5 wheels, would you design a plane without wings. Why do things keep evolving into crabs. Fact is, aliens would probably look vaguely similar to life on earth, there's certain evolutionary maximums that just work
Furthermore, the universe is a fractal so patterns are repeated.
@Private-wj4nd absolutely 💯
But aren't red dwarfs a lot more active, and therefore more more dangerous? Or could there be some mechanism that can protect a planet from the extra flares they put out? And what can prevent a planet from being tidally locked since the habitability zone around red dwarfs needs to be so close?
I remember a astrophysicist saying we dont think certain stars (forgot which one) are capable of creating a goldi lox zone for an earth like planet. but in reality it is possible if the planet had a thicker atmosphere with something like sulphur to trap in cold/heat. ironically, many alien encounter stories mention they smell like sulphur. but if we're ignoring those certain stars, theres potentially a massive amount of potential worlds that we've been ignoring the whole time. i wish i could find where i originally heard that statement...
Thank you so much for the mind blowing content!
This is one of the most interesting video i have seen ! Thanks 👌🏻
what i like to think about when it comes to this topic is "im sure humans once thought our ocean was empty at one point aswell"
This is the exact thing I've been thinking. I was always wondering why are scientist always assuming life will need water to survive while it can have totally different structure.
Short answer: because you need a solvent for life’s chemistry and water is a very good one. Longer answer: Because water is such an effective solvent for a wide range of compounds and because you need a liquid solvent to do chemistry at low temperatures. Water has an unusually wide range of temperatures and pressures it is liquid. This is promoted by solid water being less dense than liquid, allowing insulating cover of solid (ice) over liquid (water) keeping bodies of water from rapidly freezing solid. It has a high capacity to hold heat, so it smooths out extreme environmental temperature shifts. And it has strong surface tension which is important in the transition to life on land, among other things. And it is critical to the one example of life that we know about.
All biochemistry occurs in water
Once you solve immortality, whether we are immortal or the alien extraterrestrials are in mortal than time travel distance that light your speed isn’t such a problem. There are some projection videos that say by the year 2100 we may have the ability to bioengineer ourselves to become immortal. So then Traveling 30,000 light years isn’t that big of a problem to go on vacation
As per Jack Cohen and Ian Stewart's "Evolving the Alien: The Science of Extraterrestrial Life" [2002]? - the book originating with a lecture that Cohen had revised over many years, which he called POLOOP, for "Possibility of Life on Other Planets".
That’s the sound my toilet makes.
This comment section is now under control of the Plup Club
0:37 What about the other reason we haven’t found alien life? This being that it is extremely rare in the universe, but this does not mean that earth is unique. The cosmos looks rather hostile out from under earths warm but perilously thin atmosphere.
Blue stars are big and hot, but burn so fast they have short lifespans. So short, it is unlikely life would have time to evolve there.
On the other hand, the opposite is true for red dwarf stars. So they have a lot more time than Earth to evolve complex life. So even if complex life needs much more time to evolve under those conditions - it has that time.
@@KaiHenningsenyeah but all of our energy comes from the sun, so if the star isnt giving the planet enough energy then complex life wouldnt have enough energy to evolve
@@Scotty-vs4lf - In a simple way life does not need energy to evolve. All that life needs is energy to survive and multiply. The ones that do this better will be around for the longer term and evolution is the passive (no extra energy needed) result. What isn't discussed is how to determine the minimum energy needed for complicated life forms. Specifically is there an energy saving in being a multicellular wolf on Wall Street life form versus just remaining the best possible microbe under the red dwarf.
Assuming their concept of time would be similar to ours.
@@pendarischneider yeah evolution doesnt require energy (well any more than is needed for survival to begin with)
the problem i was thinking about was that complex life forms inherently need more energy for larger brains, and bodies that are useful to actually do something complex. if a worm had 10000 iq i still wouldnt consider it complex cuz all it can do is slither around
Cool! And I definitely opt for more David Bowie samples.
That lady makes me feel like I'm in 1st grade, and she's a college professor?
Very informative and interesting video. Amazing examples of thinking outside of the box.
A terrific video, Dr. Ben! Lots of great interpretation by you to explain some otherwise complex principles, with lots of relevant "b-roll" and the occasional cute clip. I recently read Dr. Kaltenegger's enjoyable book, so it's very nice to see her and her colleague talking about the challenges and what we should actually be looking for. Personally, I suspect the universe is full of planets hosting bacteria, and maybe a few with complex life, but highly doubtful we'll find technologically advanced life -- even here on earth, advanced life (radio waves, etc) only accounts for 3*10[-6] % of our planet's existence! Don't blink, ETs, you might miss us!
I am now convinced the Artist Formerly known as Prince was an Alien.
plants are green because they don't use green light, they reflect it and they use a couple of other wavelengths of light...*
thanks to this, they can better regulate their energy production.
Thanx, I learned something today
I learned this was just a bunch of theories without any evidence to back even one of the suppositions. Also, I doubt that is the worlds leading expert in that field.
I am sceptical... There are many well-studied indications that Life as we know it, really is as niche and special as we find it to be. For instance, there's at least one study that shows that red dwarf M-class stars could be detrimental to the evolution of complex life. These stars generate too little ultraviolet for photolysis of carbon monoxide, making atmospheres toxic to oxygen-breathers. And oxygen of sufficient levels is what made the Cambrian Explosion possible. Also, there are good reasons to deduce that green plants have an edge over other photosynthesizers in our Sun's light. Microbial life may be everywhere, but complex life with potential sapience may limited to Earth analogues around a yellow dwarf star with a moon and plate tectonics.
I see two problems to be solved in the search for Life:
1. Life is based on Physics and Biochemistry. Any life still has to conform to basic natural laws, and thus is limited to be physically possible. Hence Life does not differ in principle to non-life places.
2. Life evolves and thus with time will use all available resources. It also means that with time, it will use all possible energy gaps, making its detection more complicated. On Earth for instance, the current oxygen levels are not the highest anymore. It's possible that Earth in the future will have even lower oxygen levels, because later iterations of complex Life will be even more efficient breathing oxygen and thus can cope with increasingly lower oxygen levels.
Thank you, great episode. I bought a couple of Nick Lane books, and Alien Earths will make a great counterpoint!
Edit: folks if you don't know Nick Lane, professor of evolutionary biochemistry at UCL, look up his lectures right here on YT. You'll get a lot more out of it if you have some college level biochemistry to start with, but not crucial.
We haven't even seen the actual surface of any exoplanet and yet we are asking "Why is alien life so hard to find?"
How about we wait until we actually start looking. We've barely begun to look. It's like Columbus taking a little boat a few hundred metres off the shore and saying "Sheesh, what does someone have to do to find India?"
wonderful visuals, what a well produced video! great for kids to learn something :)
No one mentioned life around the deep sea vents. I understand that it is a very different way/place to live.
wow, great video 😊
Isn’t the main issue with planets in the habitable zone of red dwarf stars is that they would have to be too close to the star and be exposed to too much of its radiation? And also too close to its gravity well and possibly be tidally locked to the star? And that solar flares from the star would happen too frequently to allow life to gain a foothold there?
The main problem is space weather. Star wind, outbursts of plasma from Red Dwarfs. A Neptune planet in the Goldilocks zone with just sufficient atmosphere would be a potential life source. Sufficient atmosphere for the Star wind to blast away enough atmosphere to leave a thin trace, similar to the Earth's atmosphere in density after the Star's youth.
Red Dwarfs initially have very active space weather which reduces as the star ages. If the active phase leaves a planet with a thin atmosphere, and a star stable enough for a stable atmosphere, there is no reason life wouldn't develop.
(A thin atmosphere is needed for photosynthesis, light has to be able to penetrate. )
Tidal locking while awkward, does not preclude life. A Neptune type planet, with a radius bigger than earth, would have a lit area as great, or greater than, as earth's land area. Tidal locking has the advantage, the lit area would be lit continuously
Transit method of detection tends to find large gas giants and super earths around red dwarfs where chance of life like ours is already low. We need more sensitive methods to detect rockier earth like planets around G type stars to find life that may look more similar to what we have on earth. So current sample size is going to favor infrared life because we were not good enough yet at detecting planets that would harbor life in the visible spectrum
👏 Great video 👍
Her voice is soo calming
You mispelled annoying
'It's life, Jim. But not as we know it.'
Excellent video. Thank you.
The color may be different but those microbial ecosystems are biofilms, aka slime. And that’s the way life on earth existed for most of the time life has been here. For all the speculation on what form alien life might take, we already know what most alien life will look like, at least to our eyes: slime on rocks.
We haven't found life because the universe is really big, and most of it is unbelievably far away from us.
Stars and planets made from the dust of larger supernovae would potentially have stable isotopes of heavier elements than we do. I wonder how that might factor in.
I think that alien life will have the form of a bunch of electric marbles being pushed around by 10 legged ant like things.
0:33 only place we found life... Umm how many other places we been? When did we make interstellar travel? Or even just a camera capable of capturing any information about the inner atmosphere...
Did you not watch the video? He explains very clearly how we currently hunt for life on planets, moons and exoplanets. We haven't found the spectrum signatures yet that match the signatures here on Earth. So yes, Earth is the only place we have found life. And yes, we have also travelled to other planets and moons and taken and analyzed samples. Only a handful, but you don't seem to understand how the hunt is done. It's primitive, but we have looked at over 5000 planets.
@@High-Tech-Geek No 33 secs in and at that point idiotic obvious but not helpful statements were made. Phrasing was also intentionally done in opposition to life existing.
Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space. - Douglas Adams.
It's like closing your eyes and saying you can't find single celled organisms. First of all you probably won't see most single cell organisms with your eyes open... Much less with them closed. The rest of the video just goes on to say the same. We don't have the technology yet. Got a few general ideas.... And sure we are looking but we don't have the tools yet.
Saying we haven't found life is like saying the chicken is cooked as you watch it lay an egg. It ain't even prepped to cook...
@@limsalalafells I understand what you're saying, but spectroscopy analysis is pretty cool. It can tell us the composition of the atmospheres around these 5000+ planets. Imagine if we find oxygen and methane gases in the same proportions as here on Earth? That would be a good indicator of life. It wouldn't confirm it, but it would be a great sign. But the lack of seeing these elements so far in the right proportions and on the right type of planet speaks volumes. We haven't found these proportions yet.
But the whole point of this video is to say that maybe life on another planet doesn't emit the same gases that life on Earth does. So they are looking for other combinations of gases. Very cool stuff.
@@High-Tech-Geek all great, bad intro.
If I start a conversation by saying your worthless and will never do as well as your great grandfather. Explain his achievements loses some of it's meaning to you.
If instead I start by saying you've got a lot to strive for, or you got potential.... It puts the story about your great grampa in a whole different light. While you still may not live up to the same standards you at least aren't being knocked down before you have a shot.
Another thing I keep thinking is if a civilisation 1 billion lightyears away looked directly at earth, they wouldn't see life either.
OR we stuck our hand in a glass of water and declared "I now know everything there is to know about the ocean. nothing to see here."
As a child I was always annoyed as to why they always thought that alien life would resemble our form of biology...thankfully they are shifting their thoughts process
Based on the countless Star Trek and other space movies I have seen; most aliens look amazingly like humans. Also, outside of our immediate solar system, most planets / moons not only have a climate suitable for humans to be on without a protective suit, but also have breathable air. We are unfortunate enough to only have one planet, Earth, that meets those criteria. Even more amazing, the majority of these planets also speak very passable English.
why isn't anyone talking about K class stars? why are they always forgotten. they are better than M-class stars. and there are more than sun-sized stars.
If my grandmother had wheels she'd have been a bicycle
12:31 I didnt know that scientist had only kept looking for "green life". Im sceptical of that statement.
The most likely way intelligent life will be surprising is an equivalent to an elephant. Human life nearly disappeared 900,000 years ago due to a deep ice age period. If the earth was slighter colder, elephants would be the dominant life form.
Elephants have been shown to use names for individuals, and they are capable of communicating via the ground using infra sound frequencies, allowing them to talk to each other when they are seemly apart.
It might be that life manages to evolve on a planet around a bright star where the planet was slowly spiralling in, but, somehow, perhaps due to the gravity of gas giants in the system, gains a more stable orbit.
It's an unlikely scenario, but with an estimated 10 to the power of 24 planets in our observable Universe, not quite as unlikely as it first seems.
No lie I thought scientist or biologist looking for life already took this into account, I didn't know this was a revolutionary idea, like even a video game like No man sky predicted this
I have seen (and smelled) sulfurous life in a bright sunny shallow brine pool that was pink. Not sure if it was a type of algae or bacteria.
Wish you all the best man. You are a true bikers treasure.
700 nm is NOT the Far-Infrared! 700nm is barely into the Near-Infrared. That’s why it’s called the Red Edge and not the Far-Infrared Edge! FIR is more like 100,000 nm! Sigh…
Good catch. I'm not sure what happened in my brain here.
@@DrBenMiles Alien mind controlling parasite. Don't worry, it happens to the best of us. 😄
No need to be condescending, he simply misspoke
Edging the infrared spectrum
True. I study cyanobacteria which use far-red light 700-750 nm. So it is "far-red" not "far infrared".
If the oxygen crisis didn’t happen and kill the purple bacteria, then the purple bacteria would have evolved into purple trees and purple people, and even purple chickens. Our world would look a lot more like the majority of other planets hosting life right now
It never ceases to amaze me the arrogance of scientists who think that they understand all the parameters constraining the formation of life.
It never ceases to amaze me the arrogance of commentors who use the blanket term "scientists" without being able to name a single one who thinks they understand all the parameters constraining the formation of life.
I like to think aliens are species that don’t survive off of meat or eating, and looking at earths life got morbidly horrified and never came back
FWIW I suspect that simple life will be very common in the universe but intelligent life will be very rare as the hurdles to evolving higher organisms are very high.
The only alternative to that is that life on Earth was a completely statistical freak and we are unique in the universe.
Somehow that feels unlikely to me but your guess is as good as mine.
No mention of alternate forms beyond carbon based life. Maybe a follow-up that goes back a stage to chemistry and discusses which elements could be built into chains (e.g. silanes) would be good.
It's pretty much carbon or very unlikely silicon, everything else can't form life in any way that we can imagine.
To elaborate, carbons ability to form long chains is leaps and bounds ahead of silicon which is in turns many leaps and bounds above anything else.
Nitrogen compounds under huge huge pressures can have interesting chemistry. Also, other liquid apart from water can be used. Some bacteria even on Earth live in liquid CO2 lakes on the ocean floor.
@@KateeAngel I assume you're talking about Qian et al., 2016 Nature paper ("Diverse Chemistry of Stable Hydronitrogens, and Implications for Planetary and Materials Sciences"). I wasn't aware of this paper. It demonstrates nitrogen can form very long chains under pressures over 36GPa (about 5.22 million psi). This conditions do exist deep inside gas giants. But one problem jumped out at me and did not escape the author's notice either. As they say "Nitrogen-based life could be possible, but the likelihood of this is highly limited due to high temperatures in these planets’ interiors, which could make lifetimes of metastable compounds too short."
Use of a liquid other than water seems far more likely than silicon or nitrogen based life. Water just has a combination of many chemical and physical properties useful for life, but those are not unique to it. Even so, living in a liquid is not the same as having biochemistry based in that liquid. The bacteria living in or at the edge of undersea lakes of CO2 still use water as their intracellular biochemical solvent, not liquid CO2.
Hey, I'm signed up for notifications, but I see notification for all the other youtube channel stuff but no video. How do I fix this so I don't visit for shorts or other stuff
It’s a big universe. Odds are there is a species that looks like Greys out there.
Or maybe it’s an infinite universe, which means there are an infinite number of species that look like Greys.
5:17 Fortran… woohoo! 😍
I was waiting for a mention of high levels of anthocyanins in the early plant chlorophyll .
Very easy reason: space is huge. Huger then you can imagine.
I thought that even regular plants were once purple, even to the point that many dinosaurs ate purple plants.
Getting away from Chlorophyll is one step. Getting away from water is another.
Getting away from STP is another ("standard temperature & pressure")
Life doesn't even need to be molecular....or even atomic.
There could be sentient plasma ("elementals") based life forms on the sun and we'd have no idea what we were looking at.
the way she talks is super-annoying and offensive: as if she thought that she is speaking to toddlers. which probably is true: she probably does perceive any laypeople as dumb toddlers.
I appreciate her scientific knowledge, but it can’t justify such an astonishing level if arrogance.
I'm glad you adressed the fact that life might look entirely different on an alien world. Whenever there is a show saying that we're looking for oxygen and water I immediately discard the study because they are too narrow minded to ever find life.
They do that because it’s easier, it narrows down our options
When I was a kid the science text was certain that our star was the only one in the universe with exoplanets. Just saying
If any one of those purple planets is in some early stage of life, by the times their light reaches us, they could have already evolved complex green life and the stuff that goes with it, like intelligent life. That life might have already invented faster than light travel, and be headed toward us, looking for a Planet B of their own
Many bacteria which use infrared are still green to our eye. Like green sulfur bacteria. Yet everyone talks only about purple bacteria...
Hang on, isn’t alien life ‘grey’?
Always, unless it isn’t.
Might have to redefine 'life'.
Maybe we have more 'life' on Earth than we currently know of
It should start with "hi, 42 here"
0:36 We're minuscule, while the Universe is incomprehensibly ginormous and unfathomably old. _THAT_ could be why we've not found extraterrestrial life.
And if I wanted to watch a music video, I'd watch a music video.
I noticed two things that conflicted with what I thought I knew about sunlight. If I'm wrong, I'd be grateful for some details to correct me.
First, if green plants are reflecting infrared, wouldn't that imply that they don't absorb heat? My understanding is that infrared isn't just the wavelength of a color our eyes don't register, it's the wavelength of heat itself. Either I'm wrong (totally likely) or I just never noticed that green plants don't get warm.
Second, I'd heard that our Sun is actually a white color, tinted imperceptibly green, and that the yellow is due to the effect of the Earth's atmosphere. I can understand if chlorophyl based life adapted to the color of the light that gets through the atmosphere, and it seemed weird to me that chlorophyl would reflect the most abundant color of light, so are we sure what color the sun is?
The rest of it is fascinating. Looking for the color of the gases that might have been metabolized by living organisms when the planet occludes its sun, then looking for the color of the reflection of those organisms' actual surfaces based on what their environment might encourage them to have. It's amazing what you can at least guess at from a distance you couldn't possibly travel with current technology.
14:55 Oceans in the past were saltier? I thought that it was incremental and water was less salty.
Even if this were so, it wouldn't help solve the Fermi paradox whatsoever
Wait, how could be wrong about something we have no idea exists? Dark matter.
We know that dark matter exists, we infer its existence as we can see its effects on the universe, we just don't know what it is. For example, people knew things fell to earth before Newton described gravity.
@@fractalwalrus5409 Exactly. Straw-man. Granted, you started with "we infer", in the subsequent argument you baked the conclusion into the premise. The observation is true, the cause however is speculative.... and Scientists conclude "dark matter" cause they dont want to entertain maybe they just dont have the full picture on physics. It's equally valid to conclude there's more physics out there we havent discovered yet. The idea there exists some weird form of un-observable/un-detectable matter is the science version of Jesus.