I find it so fascinating that we can now just measure spectra of planets' atmospheres. I remember discussing that possibility as a teenager with my dad, more than 25 years ago after reading about the idea. He told me I was crazy and this would never happen in my lifetime. Sadly, it didn't happen in his.
I’ve been talking about using our sun as a gravitational lens and getting a free billion times magnification letting telescopes less powerful than ones currently in space take photos like they were an iPhone in orbit with my son because I read about it. It would be so cool to get up close photos of exoplanets in my or his lifetime.
@@toosas it was closer than you vould expect. When I was home for christmas that year, I told him about JWST which was launching. He was glue to various screens the next few days reading anything he could find. We followed every detail of the launch and the initial deployment. Was a huge experience together. That was the last time I saw him alive. But I still consider it a happy memory!
It still amazes me how fast we've progressed in the last 150 years. Also going from the first powered flight to landing on the moon in 66 years is absolutely insane.
@@erik-ic3tp No, because hard work is seen as a good thing. Yes, they had less time for leisure, but they still enjoyed pleasure and leisure. I would think that they enjoyed it more, since they got less of it.
@@FLPhotoCatcher I wonder about that. If one was to gather a list of famous scientists, engineers, whatever you like, and then compare their religion to the baseline population, would you find any outliers? And then how much of that can be explained by socioeconomic status Far as I know, no one's done that, but it'd be an interesting survey
We honestly shouldn't care about aliens unless they come here. That is because it is more likely that if they come here, then they want resources like we will if we get space travel down and find other habitable planets.
Long time watcher. I just to say thank you for always being truthful about the tentativeness of discoveries. So many UA-cam channels would have made a video about the same information saying we discovered life on other planets. You guys always stay true to the science and the healthy skeptical approach. It’s appreciated.
I always love it when you say, "It's never aliens, until it is." I wish more people would come to that conclusion. Too many people, say things like, "I can't explain it so it must be aliens."
I agree with both of you. The present explanation for the existence of intelligent aliens (microscopic life would probably exist in plenty of places), is very similar to the explanation given traditionally for God. "There are trillions of stars and trillions of planets, so intelligent life should exist somewhere." Right? Wrong!!!! There is a whole lot of difference between the existence of microscopic life, and sentient, technological life. The biggest barrier I think is the existence of 'continuous habitability'. It took ~4 billion years for humans to evolve on earth. The chances that a planet will remain habitable for such a long time is incredibly low. The planets that we have discovered in habitable zone (by Kepler mostly), are most likely there temporarily. Most of them are gas giants, which migrated there after formation. All our solar system models show that planetary migration is the norm rather than exception. Our solar system is actually rare type. And stable orbit is not the only requirement. Our planet has undergone profound changes in these 4 billion years. We started with CO2 and methane rich atmosphere (both potent greenhouse gases), and had an oxygenation event 2.3 billion years ago. Sudden loss of greenhouse gases could have easily frozen our planet. But we got lucky. Our sun also increased in luminosity, from 70% to present 100% brightness. And will further increase leaving earth inhabitable in another 1 billion years. (That's normal evolution for all stars).. Our Goldilocks zone also has shifted outwards. It's a phenomenal coincidence that earth remained habitable for 4 billion years. Any of the above factors could have easily frozen or boiled our planet. We have two examples in our own neighbourhood as proof of shifting habitability of planets. Then there is question of oxygenation. It may or may not happen on other planets. Even with a lush cover of blue green algae, it took almost 2 billion years on earth. Will it be possible on all planets? What about tidally locked planets? They have only one hemisphere facing the sun. And even that is partially habitable due to eyeball effect. It will definitely take much longer, if at all oxygenation happens. And even if complex animals evolve, they may not reach sentience. Only one genus on earth managed it. And we are the only species that survived. (Other 4 including Neanderthals went extinct). And lastly, humans evolved almost 0.3-0.5 million years ago, and we didn't discover technology until the last 500 or so years. Before that, we lived perfectly well as tribes. And the rapid technolgical advancement is largely owed to fossil fuels, almost all of which got deposited during a specific era ~350 million years ago. There are too many coincidences here, for aliens just to evolve by sheer numbers. They might be there, but intelligent, technolgical forms are not so straight forward as it may seem by numbers alone.
Science is just freaking amazing. The things we can suss out given a good scientific framework and decent data... I'm forever amazed. On a different topic, I think we need to take steps to ensure Dr. Matt remains the host of PBS Space Time for the remainder of spacetime. Hopefully this involves interesting incentives and the like, but if not... well, the ends justify the means. Also, there's the mortality thing, but I'm sure that can be worked out as well.
One of the problems with finding life seems to be that the places that are easiest to look, planets close in to stars where a lot of transits can happen in a short time, are nothing like the one planet we know has life. Not that this is useless, there's a lot of science that can be done besides searching for life and if we did find life in such a different world that would be VERY eye opening about what life actually needs. But it does mean that our threshold for believing a signal is life will be higher in a system/planet that's so different from our only confirmed life. All reminds me of this joke: You're walking down the street at night when you see a person looking on the ground under a lamp post. You ask them what's happening and they say they're looking for an earring that they just lost. So you offer to help and after looking with them a while you ask "are you sure you dropped the earring here?" The person you're with looks up surprised at the question and says "oh heavens no, I lost it over there" pointing down the street into the dark. So you respond confused "but if you dropped it over there why are we looking here?" The searcher replies "well this is where the light is."
Exoplanet hunters are well aware of this bias. Remember when all the exoplanets we were finding seemed to be "hot Jupiters?" That was because Jupiter-size planets orbiting close to their star was the only type of planet we were capable of detecting back then, leading many so-called skeptics (i.e. science deniers) to claim we would never find anything remotely like another Earth. Thing is, innovation in technology and method will continue to improve, so what holds true now is likely just a temporary state of affairs. Scientists know the goal is to find Earth-twins around Sun-like stars and study their atmospheres, which is why they are already hard at work on JWST's more capable successor. The only confusion here is among the casual observer who jump to the wrong conclusion based on the current state of a fast moving field of study.
Thank you for coincidentally releasing a video on my 50th birthday, Matt and crew. I couldn't ask for a better gift. Got the day all to myself, going to see family tomorrow. I'm excited to watch this video and then dive into the Black Hole playlist for the 100th time and counting. Cheers from an old fan (holy cow I'm 50, how did this happen?) and thank you for everything you do for science.
Thanks for going through the explanation of why its thought K2-18b is thought to be a Hycean planet rather than a mini-Neptune. I haven't seen much discussion of that elsewhere and I think it's an important point. I also think calling the presence of DMS a 1 sigma detection is fair but the paper did find a higher level of confidence for DMS detection at 0 offsets, to about a 99 percent. The authors presented the data with 0, 1 and 2 offsets to account for potential error due to the gap between the two detectors that were primarily used for gathering the data. But the paper did say the 1 offset detection, which was 1 sigma, was probably the most realistic, so calling it 1 sigma, or about 68 percent probable, is probably the most fair interpretation.
In Star Trek, Spock would always announce the type of planet the Enterprise was approaching, using a single letter to indicate its classification. After watching this episode, we probably need a far more robust classification system than our 26 letter alphabet can accommodate.
Make it so. In tng there was also an episode where Q showed the sludge in which life on earth originated from. Hopefully in the future we'll have Data to help.
If you look at the actual classification, it’s all over the place and clearly meant to be used from a story perspective first and foremost. As a classification system the Star Trek one doesn’t actually make sense
Big blue ball of oxygen and water? Very, I'd wager. Not to mention all the traces of various pollutants in the atmosphere, and the rapid change in the planet's albedo as our civilization spread around the world -- e.g. wholesale deforestation. Any advanced alien civilization would quickly realize that by far the easiest way to explore the galaxy is to build the biggest most capable telescopes possible -- likely whole clusters of them in space eventually. If we're not hidden from view by intervening stars, dust, or gases, then anyone in range will eventually spot us.
Due to molecules produced via industrial processes we actually have even more significant signatures that can be sought after. But SETI's goal is not for these, as we expect diminishingly few civilisations to have anything like that.
1) Having a planet with a supercritical ocean would make for some pretty interesting chemistry and physics. For instance, if there's areas of the oceans near the critical point, tiny fluctuations in temperature would cause massive changes in density, which would create a massively turbulent zone. Additionally, the osmotic pressures would, if I'm not mistaken, equilibrate EXTREMELY rapidly, which could make cellular life extremely difficult. 2) I'm probably preaching to the choir here, but now that we've got a proof positive of the JWST's design, building another one should be radically cheaper than the original and its associated R&D. How about we cut 1% off our defense funding in the US for a single year, take that 18 billion dollars, and build+launch roughly 9 more of the things?
@@Rebel7284 your leaders go through allot of trouble to convince the public that universal health care is a bad idea they love to say its. communist and they also love to say that the richest country on the planet cant afford universal health care when many western nations have been providing health care to their people for a long time now. so conclusion as long as the democrats nd republicans are the only parties getting into power you will never have it
Not if they did the logical thing and killed most of us, then domesticated and/or experimented on the rest of us. Why would an alien give AF? They probably wouldn't have survived long enough to discover us if they were stupid, and cared about stuff that didn't matter, like some inconsequential and inferior life form, which is precisely what we would be to any alien which discovered us.
The other alternative is, that the aliens have terrible beer. DMS is a common bad taste in beer, if the mash didn't cook long enough. In beer it's usually described as the taste of green peas.
I still remember when Matt took over for Gabe. This guy, these people, work 49 or 50 weeks a year. Sagan can't hold a candle to him or to the PBS ST staff as science educators. Ok fine, let's call them peers of Sagan. Matt and his writing staff and production staff deserve to be on the same level as Feynman; peers of Feynman and nothing less.
I've only seen two vidoes with Gabe. The first had him answering questions like he was an auctioneer lol. The 2nd had him answering questions about how fast he answered questions
@@olafsigursons Any aliens out there don't have any choice in the matter. You can't hide the effects of a planet filled with life, technological or otherwise.
"...let me add a note of extreme caution. The detection...is at the 1 sigma level." As a biologist, I'm always amused by how high the standard for physics evidence is. It's good, but you almost never find 5-sigma evidence for anything biological...
Working on something adjecent for my thesis, looking for signs of life in the atmosphere. People really get caught up in the idea that there's so many planets in the universe, so there's bound to be life. This assumes that every planet has an equal probability for life to occur. People leave out and forget how many filters there are, just by utilizing laws of thermodynamics, chemistry, and nucleosynthesis thst deter life ubiquitously.
I think _life_ might not be super-rare, but _intelligent_ life very well could be unique to this galaxy. Because some of the filters that might not be insurmountable for simple, unicellular life like bacteria, may well be insurmountable for more complex, multicellular life.
Why shouldn't we be caught up by the idea? The odds of Earth being the only planet with life on it in a Universe with trillions of planets are incredibly low, even after you filter out everything planetary type other than Earth-twins. From what I can see, far more people are forgetting that "alien life" doesn't just mean little green men in spacecraft, but every form of life down to the simplest form of single-celled organisms, which didn't take very long to arise here on the primeval Earth, relatively speaking. There's a vast ocean out there left to be explored, and we have yet to do more than dip our big toe in the water. No scientist is under the illusion that life exists under every rock, but the idea that there's no life of any kind anywhere else in the Universe is borderline nonsensical. The more we have discovered about the Universe, the less unique our own position in it becomes.
@@EnglishMike -- _"The more we have discovered about the Universe, the less unique our own position in it becomes."_ That's not true. Although we've discovered that solar systems with planets are much more common than previously thought, Earth appears increasingly unique among those planets as we learn about the contingencies required for life to arise--especially complex life. For example, red dwarfs, which are several times more common than G2 stars like the Sun, have a liquid-water habitable zone that's close enough to the star to tidally lock the planets within the zone. This makes the front too warm for liquid water, the back too cold for liquid water, and a ring in the middle with perpetually extreme weather. Additionally, the formation of the Moon was an incredibly unique event, with the impact that produced it involving the right combination of mass, velocity, and angle of impact to scrape or boil away almost all (but not actually all) of the Earth's water. (Otherwise, the planet would either by dry or locked beneath an ice layer like Matt explains at 15:30.)
This is why the Dark Forest hypothesis falls apart. The aliens already know where we are, and soon, we will know where they are. In space, staying hidden is impossible.
In the 1993 point-and-click adventure game Star Trek: Judgement Rites, the final missions involved the crew of the Enterprise being tested by an alien species who identified themselves as the Brassica. Brassica is Latin for cabbage. The cabbage aliens have been foretold through computer games of old!
Oops -- someone didn't do their research. I once wrote a book where one of the main characters was a little alien girl called Pyria. I eventually looked up the word online only to find out it's another name for periodontitis, or gum disease. However, I liked the name too much to want to change it by then.
Brilliant as usual. I think a lot of lay people crave to understand more about how we're 'seeing' characteristics with JWST and this does a nice job of briefly explaining how indirect measurements are used to calculate features.
Thank you so much for all these interesting explanations! It might have been useful to also explain why a molecule emits or absorbs IR light. To do so, the light changes the dipole moment of the molecule- causing it to wiggle in specific ways (its normal modes).
I love it when spacetime veers into chemistry and biochemistry. Also, Hycean Planets is a great term. Also also this detection "madness" reminds me of the Venus Hype a few years back; have there been any episode-worthy updates on that front (other than, "its not aliens", of course)?
its hard to fathom how just how incredibly tiny that sample of light must be to come from a small, dim star which then passes through the sliver of atmosphere of an even smaller planet 100something lightyears away
I had not considered until he mentioned it, that it's only that relatively thin layer of atmosphere that is detectable regardless of the size of the planet.
Saving this video. Greatm explanation on how we can tell such extraordinary things about planets so far away. Way better than me muddling my way through the basic concepts.
So what would aliens see if they looked at Earth's atmosphere from 100 light years away? Would they see DMS? Would they see all the molecules that would give them a 5 sigma that life exists here?
No expert, but I think if they picked up the traces of CFCs in our atmosphere that might be a fairly good hint. Idk of any natural sources of such molecules, they are very definitely products of the laboratory. (Of course, following the Montreal protocol CFCs have rapidly been depleted from the atmosphere. But from the perspective of an alien 50 lightyears away, that hasn't happened yet!)
Depending on their tech level, yes. The most important would be oxygen, a gas that's rather tricky to produce in large amount abiotically. That and methane would be hard to ignore by themselves. DMS would be harder, our atmosphere's small and oxidizing, and probably wouldn't actually be necessary. Interestingly things like CFCs present might even tip them off that we have industry.
@@garethdean6382 Agreed. High concentrations of oxygen should be the easiest indicator of photosynthesis and would be detectable out to at least 2 billion light years. Industrial indicators would only be visible out to 100-200 light years but that's an indicator of advanced life.
10:30 this gives a somewhat prophetic meaning to the 1981 French film starring Louis de Funès _"La Soupe aux Choux "_ ( _"The Cabbage Soup"_ ) 😉😳 An alien being attracted by Earthings eating (an metabolising 😜) cabbage soup.
Sometimes I wonder if intelligent life evolves on a planet with a high surface gravity, like 15g+, will ever be able to get into space. It would be terrible to be stuck at the bottom of a gravity well only being able to see space but never travel to it.
@@donbruce8234 the planet in question is only 1.3g and super earths go up to about 3g but a surface gravity as above isn’t uncommon for larger planets, the highest surface gravity of an exoplanet we discovered is about 600g.
The planet here is only like 1.3g, but to answer your question more generally getting to space becomes exponentially harder with higher surface gravity. For example escaping 2g with standard hydrogen rockets would require them to be ~4 times more massive than the saturn V just to get into orbit (keep in mind the saturn V was built with mars in mind). Using nuclear rockets would help but you'd run into the same exponential barrier of impracticality eventually.
Here’s the thing though. The first detection of life may well be even within our solar system. If there’s in fact a giant ocean that massively exceeds Earth’s, under a sheet of ice in Titan, and Saturn’s tog on Titan, as well as its residual core heat, is enough to sustain chemistry, it could well be home to life, but a very different type of life from one that lives on a planet’s surface, relying on energy from a nearby star.
Sometimes I feel like exobiology is like being a Skyrim guard. An alien slaps you in the face: "Who's walking there?!" You explain away your own observation: "Must have been the wind..."
On the other hand, no dragons have popped up recently to set fire to our houses. With something so big you really do want to be sure. We've embarrassed ourselves too many times before, jumping the gun.
@@ratking1330 I didn’t say it didn’t warrant study. I wouldn’t know. My question is because I’m confused by 32% resulting in “most” sigma 1 results being false positives. I was hoping someone could explain further so I could understand at least a bit more.
IF everyone was honest and unbiased and logical, then 1 in 3 sigma-1 results would be wrong. HOWEVER, scientists are motivated to report unusual results, to HAVE a result to write a paper on. They want to succeed and often have multiple ways to analyze data to ensure that they can claim a result. As such many sigma-1 results are, if not fraudulent, then biased. And as such many fail when scrutinized. But sigma-1 isn't an average success over time, it's a mathematical definition. It MUST have a failure rate of 33%. The higher rate comes from people using it incorrectly. Extra-virgin olive oil is still a thing, even though most of it is faked. So the 'true' failure rate of anything is higher than what might be expected from pure honest math.it's unfortunate but true, a sort of 'nobody talks about it' thing in the sciences.
That "32% chance" has nothing to do with the true chance (this is one of the common misconceptions of statistical hypothesis testing, due to the weird way "significance" is defined.) What it means is that assuming there really is no DMS, we'd only expect the observed results 32% or more of the time. Meaning that the results could be caused by noise 32% of the time. Note that it isn't saying anything about the true probability of an event, rather just how unlikely it was to happen by chance *this one time* (with enough trials, you can still run into rare chance events.) And when the underlying event is super rare (like DMS occurrence probably is), then most DMS detections will be false positives. To demonstrate the above: An analogy I like to make is with rare diseases. You can use Bayes' Theorem to calculate the probability of having a rare disease given that you tested positive. If the false positive rate (AKA the probability you receive a positive given that you didn't have the disease) is low but the frequency of the disease in the population is much lower, then the probability of having the disease after receiving a positive is also low. That's because there will be way more false positives than actual disease patients, since the probability of a false positive-while low-is still much higher than the general population occurrence rate of the rare disease.
Edit: apparently, I know nothing. Yeah, a hydrogen atmosphere should be fine. ------ I'm just a dude with a B.S. in atmospheric / oceanic science and an interest in astronomy. That being said, I'm pretty sure a hydrogen atmosphere would diffuse into a liquid water ocean and cause it to become _extremely_ acidic, meaning just about all you'd see would be extremophile bacteria. A hydrogen atmosphere seems bad for life, but what do I know.
While acidity itself doesn't influence density, it can influence external factors that can change the density of a fluid. There's would likely be pockets of less acidic and more acidic water. It's not quite as much as a deal breaker as it seems
@@ratking1330 on a planetary scale, sure, differing pockets could form due to rising or sinking action in the atmosphere or due to sequestration into rocks, but... with an atmosphere that is so highly composed of hydrogen, over the course of millions of years, even assuming little to no mixing, the hydrogen would diffuse even into the deep ocean.
I'm not sure I get you; hydrogen is pretty neutral, is it not? it doesn't dissociate much in solution so where would the acidity come from? I know H- isn't stable in water, it produces OH- and hydrogen, so I"m not sure where you'd get a source of unbalanced H+ from. I think the bigger issue would be if the rock was cut off from the water, leaving you with a very nutrient-poor ocean.
So we need a new equation for the probability of life becoming intelligent, discovering a branch of science that leads to interstellar travel, and also factir in evolving to recognize the value of maintaining diversity. Then, add in its range of influence and ability to constrain less advanced life that would try to colonize everything and destroy us. So that would give the probability of discovering other life that's already here. But one has to also take account of the probability that small groups of oligarchs have propagated disinformation and maintained a cover up, then this becomes revealed. Oh, wait a minute, isn't this just what's happening?
A premise of "2001" and many other sci-fis was that there would be widespread alarm if the discovery of the extraterrestrial life was announced publicly. And yet for nearly 200 years, going back to the New York Sun "Moon Hoax" in 1835, the reaction to numerous pronouncements of life detected elsewhere has generally been only mild and fleeting interest.
We like to think that we're poetic.That we'd appreciate life off Earth for its deep philosophical meaning, for the perspective it would give us on our place in the universe. Or that,in tragic irony, we would recoil in horror and scour the knowledge from our world with fire. But we're dull. Looking for the newest shiny thing. A war headlines for a week, a nuclear catastrophe is soon buried beneath celebrity gossip. Our banality is perhaps the truth we fear to face.
Alien scout vessel: "Sir we have located a class M planet. Sentient life forms and structures detected, but they don't pass the intelligence test I'm afraid. They are destroying their own ecosystem willingly due to something called "money" Alien Captain: "That's a shame.... Well lets move on to another system and leave these doomed fools alone."
I have notifications for this channel set to all but I am not receiving notifications. This episode just appeared randomly in my feed after refreshing a few times.
What I have specifically not heard concerning alien life is that it is possible that *we* are the advanced alien civilization that we always assume some other entity would be. We may simply be that alien life before it has advanced enough to jump around the galaxy. We may be the most advanced life in the galaxy or even the universe and the truth is that our greatest grandchildren may be the aliens other future life dreams of like we are doing now. Who knows?
0:45 - Well, we don't have a solid explanation for "Wow!" signal. Doesn't mean it was an alien tight beam communication signal strafing us accidentally, but it is not anything equivalent to the signal that marked the discovery of pulsars. We will probably never know.
Rather than "Grey humanoid with big eyes 👽 " i bet the first extraterrestrial we encounter just a single cell organism like a bacteria but from other planet like Mars or from Moon like Titan.
i have to imagine that once we find the first planet with life, we will go, "OH, we needed to reconfigure the thingamabob to capture the sub spectra, etc, etc....." and then we will be finding life all over (though still a very small % of all planets).
Actually, oumuamua isn't technically explained yet by the scientific community at large. So the hypothesis that oumuamua is a probe of some kind sent by aliens is still valid
Humanity should build its ideas and life that there are indeed living beings like him in some way in the depths of the universe, even if he will not reach them and will not see them, this is the right logic to touch the facts with.
If I could time travel, I’d go find Johannesburg Kepler, and show him this video, along with a short explained about what atoms and molecules are, and what the electromagnetic spectrum is, etc. I’d give him those explainers first, then show this video, and then say thanks for your contributions.
We live in a relatively young universe and there is a greater possibility that we are the first inter galactic or could be the first inter galactic species in this universe. If there was any advance civilisation millions of years ahead of us , they would have definitely contacted us or atleast there would have been some kind of evidence related to them . I am sure that life and an advanced life like multicellular organisms or some intellectual species is not that easy to originate.
I'm in that camp. If we do find alien life, it's most likely to be bacterial or something microscopic that can survive harsh conditions. I remember years ago there was a major report about scientists possibly finding fossils or remnants of microbes in a meteor or something. I was super excited but then I heard nothing for many years. The next time I heard anything about it, it was on PBS SpaceTime and Dr. O'Dowd explained what happened. I was glad I finally found out what happened, but also a little sad because...it wasn't aliens. It was still good to know though.
I find it so fascinating that we can now just measure spectra of planets' atmospheres. I remember discussing that possibility as a teenager with my dad, more than 25 years ago after reading about the idea.
He told me I was crazy and this would never happen in my lifetime. Sadly, it didn't happen in his.
sorry to hear that he did not make it to see it but great that you have!
Sorry for your loss, but I hope you're managing to enjoy a non-vengeful posthumous told-you-so. :)
I’ve been talking about using our sun as a gravitational lens and getting a free billion times magnification letting telescopes less powerful than ones currently in space take photos like they were an iPhone in orbit with my son because I read about it. It would be so cool to get up close photos of exoplanets in my or his lifetime.
@@toosas it was closer than you vould expect. When I was home for christmas that year, I told him about JWST which was launching. He was glue to various screens the next few days reading anything he could find. We followed every detail of the launch and the initial deployment. Was a huge experience together. That was the last time I saw him alive. But I still consider it a happy memory!
@@rlosable Yours was a wonderful reminisce that I'm sure you'll treasure always. Thanks for sharing this bittersweet moment! Peace.
It still amazes me how fast we've progressed in the last 150 years. Also going from the first powered flight to landing on the moon in 66 years is absolutely insane.
That was partly due to the Protestant work ethic.
@@FLPhotoCatcher, how? Because pleasure/leisure is frowned upon by Protestantism/Calvinism?
@@erik-ic3tp No, because hard work is seen as a good thing. Yes, they had less time for leisure, but they still enjoyed pleasure and leisure. I would think that they enjoyed it more, since they got less of it.
@@FLPhotoCatcher I wonder about that. If one was to gather a list of famous scientists, engineers, whatever you like, and then compare their religion to the baseline population, would you find any outliers? And then how much of that can be explained by socioeconomic status
Far as I know, no one's done that, but it'd be an interesting survey
@@FLPhotoCatcher absolute bullshit.
everybody gangsta until its actually aliens
@@YargGlug bullshit, you ain't got no girlfriend
@@JK7Hyeah not with that pfp
We honestly shouldn't care about aliens unless they come here. That is because it is more likely that if they come here, then they want resources like we will if we get space travel down and find other habitable planets.
They will be intimidated by our salad commercials.
But what if the aliens are gangsta? Role reversal?!
Long time watcher. I just to say thank you for always being truthful about the tentativeness of discoveries. So many UA-cam channels would have made a video about the same information saying we discovered life on other planets. You guys always stay true to the science and the healthy skeptical approach. It’s appreciated.
I always love it when you say, "It's never aliens, until it is." I wish more people would come to that conclusion. Too many people, say things like, "I can't explain it so it must be aliens."
This is just the old God-of-the-gaps fallacy updated for the 21st century.
I agree with both of you. The present explanation for the existence of intelligent aliens (microscopic life would probably exist in plenty of places), is very similar to the explanation given traditionally for God.
"There are trillions of stars and trillions of planets, so intelligent life should exist somewhere." Right?
Wrong!!!!
There is a whole lot of difference between the existence of microscopic life, and sentient, technological life.
The biggest barrier I think is the existence of 'continuous habitability'. It took ~4 billion years for humans to evolve on earth.
The chances that a planet will remain habitable for such a long time is incredibly low.
The planets that we have discovered in habitable zone (by Kepler mostly), are most likely there temporarily.
Most of them are gas giants, which migrated there after formation.
All our solar system models show that planetary migration is the norm rather than exception. Our solar system is actually rare type.
And stable orbit is not the only requirement. Our planet has undergone profound changes in these 4 billion years. We started with CO2 and methane rich atmosphere (both potent greenhouse gases), and had an oxygenation event 2.3 billion years ago. Sudden loss of greenhouse gases could have easily frozen our planet. But we got lucky.
Our sun also increased in luminosity, from 70% to present 100% brightness. And will further increase leaving earth inhabitable in another 1 billion years. (That's normal evolution for all stars)..
Our Goldilocks zone also has shifted outwards.
It's a phenomenal coincidence that earth remained habitable for 4 billion years.
Any of the above factors could have easily frozen or boiled our planet. We have two examples in our own neighbourhood as proof of shifting habitability of planets.
Then there is question of oxygenation. It may or may not happen on other planets. Even with a lush cover of blue green algae, it took almost 2 billion years on earth.
Will it be possible on all planets?
What about tidally locked planets? They have only one hemisphere facing the sun. And even that is partially habitable due to eyeball effect. It will definitely take much longer, if at all oxygenation happens.
And even if complex animals evolve, they may not reach sentience. Only one genus on earth managed it. And we are the only species that survived. (Other 4 including Neanderthals went extinct).
And lastly, humans evolved almost 0.3-0.5 million years ago, and we didn't discover technology until the last 500 or so years. Before that, we lived perfectly well as tribes.
And the rapid technolgical advancement is largely owed to fossil fuels, almost all of which got deposited during a specific era ~350 million years ago.
There are too many coincidences here, for aliens just to evolve by sheer numbers. They might be there, but intelligent, technolgical forms are not so straight forward as it may seem by numbers alone.
Things are unprecedented, until there not .
I have to confess that I am an extraterrestrial
its aliens
Science is just freaking amazing. The things we can suss out given a good scientific framework and decent data... I'm forever amazed. On a different topic, I think we need to take steps to ensure Dr. Matt remains the host of PBS Space Time for the remainder of spacetime. Hopefully this involves interesting incentives and the like, but if not... well, the ends justify the means. Also, there's the mortality thing, but I'm sure that can be worked out as well.
Is Matt retiring?
@@LuisSierra42 No-- or at least, not that I know of. I just want to make sure that always remains the case. ;-)
>inb4 Futurama heads in a jar
>inb4 GenAI replication
sussy
One of the problems with finding life seems to be that the places that are easiest to look, planets close in to stars where a lot of transits can happen in a short time, are nothing like the one planet we know has life. Not that this is useless, there's a lot of science that can be done besides searching for life and if we did find life in such a different world that would be VERY eye opening about what life actually needs. But it does mean that our threshold for believing a signal is life will be higher in a system/planet that's so different from our only confirmed life.
All reminds me of this joke: You're walking down the street at night when you see a person looking on the ground under a lamp post. You ask them what's happening and they say they're looking for an earring that they just lost. So you offer to help and after looking with them a while you ask "are you sure you dropped the earring here?" The person you're with looks up surprised at the question and says "oh heavens no, I lost it over there" pointing down the street into the dark. So you respond confused "but if you dropped it over there why are we looking here?"
The searcher replies "well this is where the light is."
Exoplanet hunters are well aware of this bias. Remember when all the exoplanets we were finding seemed to be "hot Jupiters?" That was because Jupiter-size planets orbiting close to their star was the only type of planet we were capable of detecting back then, leading many so-called skeptics (i.e. science deniers) to claim we would never find anything remotely like another Earth.
Thing is, innovation in technology and method will continue to improve, so what holds true now is likely just a temporary state of affairs. Scientists know the goal is to find Earth-twins around Sun-like stars and study their atmospheres, which is why they are already hard at work on JWST's more capable successor. The only confusion here is among the casual observer who jump to the wrong conclusion based on the current state of a fast moving field of study.
Oh, that’s good.
Thank you for coincidentally releasing a video on my 50th birthday, Matt and crew. I couldn't ask for a better gift. Got the day all to myself, going to see family tomorrow. I'm excited to watch this video and then dive into the Black Hole playlist for the 100th time and counting. Cheers from an old fan (holy cow I'm 50, how did this happen?) and thank you for everything you do for science.
Happy birthday!
Happy Birthday. Just remember, 50 is like 20, but just 30 more.
@@ashtyler8 Thank you! I'm going to run with that and tell everyone I'm really a 20 y/o and 30 y/o stacked up in an old man costume. :)
Every time I use the word "coincidental" I get accused of being an anti-dentite! 🤣🦷
Happy Birthday brother!!!! I may not know you, but I wish you and your loved ones the very best in all regards and hope you enjoy many more years!!!!
What scifi movies will Matt watch this week?
I'm not sure, all I know is - it's never Aliens...
Alien: Resurrection, maybe!
Thanks for going through the explanation of why its thought K2-18b is thought to be a Hycean planet rather than a mini-Neptune. I haven't seen much discussion of that elsewhere and I think it's an important point. I also think calling the presence of DMS a 1 sigma detection is fair but the paper did find a higher level of confidence for DMS detection at 0 offsets, to about a 99 percent. The authors presented the data with 0, 1 and 2 offsets to account for potential error due to the gap between the two detectors that were primarily used for gathering the data. But the paper did say the 1 offset detection, which was 1 sigma, was probably the most realistic, so calling it 1 sigma, or about 68 percent probable, is probably the most fair interpretation.
In Star Trek, Spock would always announce the type of planet the Enterprise was approaching, using a single letter to indicate its classification. After watching this episode, we probably need a far more robust classification system than our 26 letter alphabet can accommodate.
Agreed. We'll have to move to... DOUBLE letters...
They're already using full names to describe planetary types, so I don't think that will be an issue!
Make it so. In tng there was also an episode where Q showed the sludge in which life on earth originated from. Hopefully in the future we'll have Data to help.
If you look at the actual classification, it’s all over the place and clearly meant to be used from a story perspective first and foremost. As a classification system the Star Trek one doesn’t actually make sense
26 main classes for the most important, or safe to visit, ones, and as many subclasses as you want
I wonder how detectable life on earth would be from such a distance.
Big blue ball of oxygen and water? Very, I'd wager. Not to mention all the traces of various pollutants in the atmosphere, and the rapid change in the planet's albedo as our civilization spread around the world -- e.g. wholesale deforestation.
Any advanced alien civilization would quickly realize that by far the easiest way to explore the galaxy is to build the biggest most capable telescopes possible -- likely whole clusters of them in space eventually. If we're not hidden from view by intervening stars, dust, or gases, then anyone in range will eventually spot us.
with the amount of pollution we produce, using these techniques, probably along the lines - POO I don't want to go there!
Due to molecules produced via industrial processes we actually have even more significant signatures that can be sought after. But SETI's goal is not for these, as we expect diminishingly few civilisations to have anything like that.
I'm sure the aliens can smell us from there ...
@@567secret
They wouldnt see that, they will see the earth 124 years ago.
"It's Usually Human Delusions" - Would be the most truthful T-shirt.
Honestly this is exactly and solely what just should be focused on investigating planets in Goldilocks zone. This was a fantastic episode
1) Having a planet with a supercritical ocean would make for some pretty interesting chemistry and physics. For instance, if there's areas of the oceans near the critical point, tiny fluctuations in temperature would cause massive changes in density, which would create a massively turbulent zone. Additionally, the osmotic pressures would, if I'm not mistaken, equilibrate EXTREMELY rapidly, which could make cellular life extremely difficult.
2) I'm probably preaching to the choir here, but now that we've got a proof positive of the JWST's design, building another one should be radically cheaper than the original and its associated R&D. How about we cut 1% off our defense funding in the US for a single year, take that 18 billion dollars, and build+launch roughly 9 more of the things?
What if we launch only 1 more and ALSO add universal healthcare? Or is that scenario as likely as life on any individual exoplanet? 😉
@@Rebel7284Nah, the universal healthcare can be payed by taxing billionaires. :P
@@Rebel7284 your leaders go through allot of trouble to convince the public that universal health care is a bad idea they love to say its. communist and they also love to say that the richest country on the planet cant afford universal health care when many western nations have been providing health care to their people for a long time now. so conclusion as long as the democrats nd republicans are the only parties getting into power you will never have it
Actually discovering alien life would be easily one of the coolest things to ever happen!
Not if they did the logical thing and killed most of us, then domesticated and/or experimented on the rest of us.
Why would an alien give AF? They probably wouldn't have survived long enough to discover us if they were stupid, and cared about stuff that didn't matter, like some inconsequential and inferior life form, which is precisely what we would be to any alien which discovered us.
And potentially the most scary thing to ever happen.
As a certain Vulcan would say: Fascinating
Matt and the PBS Spacetime team have brought joy and wonder to my life. Thank you.
The talk of ocean worlds makes me excited to play Stellaris again. I can highly recommend it if you like Civilization games.
Now sci-fi writers can write "cabbage aliens" into their words and claim some scientific accuracy, amazing
It's the Invasion of the Brassicans! 😱
"What, you think I'm not detectable, just because I have a CABBAGE FOR A HEAD?"
Move over "cone heads". We need some room for "cabbage heads"!
The other alternative is, that the aliens have terrible beer.
DMS is a common bad taste in beer, if the mash didn't cook long enough. In beer it's usually described as the taste of green peas.
I still remember when Matt took over for Gabe. This guy, these people, work 49 or 50 weeks a year. Sagan can't hold a candle to him or to the PBS ST staff as science educators. Ok fine, let's call them peers of Sagan. Matt and his writing staff and production staff deserve to be on the same level as Feynman; peers of Feynman and nothing less.
I remember that a lot of people complained about Matt at first. Gabe was good but Matt is the face of PBS Spacetime for me
I didn't like Gabe's style, without disrespect. I think Matt is a much better fit for space-time.
I've only seen two vidoes with Gabe. The first had him answering questions like he was an auctioneer lol. The 2nd had him answering questions about how fast he answered questions
Gabe had a lot of passion for the science and without him SpaceTime wouldn’t be where it is today
I wake up every morning and check my phone to see if pbs space time has posted
Your educational brilliance is a blessing to the world. Thank you for everything you have done all these years. I will never stop watching.
I like how near the end, the significance of finding aliens was turned into just another thing to sell merch about
Thanks Matt and team for another great video! These are indeed exciting times!
@PBS Space Time your graph @6:00 shows wavelengths in nm but it should be μm - light past the first infrared window is definitely not 1nm wavelength.
If I learned one thing on this channel it's that
✨it's never aliens until it's aliens ✨
It will never be alien. They don't want to find it.
Never aliens!
@@olafsigursons lol
@@olafsigursons Any aliens out there don't have any choice in the matter. You can't hide the effects of a planet filled with life, technological or otherwise.
Let’s hope it’s not, they will eventually get our TV broadcasts of salad commercials.
"...let me add a note of extreme caution. The detection...is at the 1 sigma level." As a biologist, I'm always amused by how high the standard for physics evidence is. It's good, but you almost never find 5-sigma evidence for anything biological...
You should try psychology. It's as close to voodoo as you can get while still being an actual science because people are weird and complicated.
And that, my friend, is why we've 'cured cancer' so many times in mice and so few times in humans. Still, at least it's better than psychology.
Working on something adjecent for my thesis, looking for signs of life in the atmosphere.
People really get caught up in the idea that there's so many planets in the universe, so there's bound to be life. This assumes that every planet has an equal probability for life to occur.
People leave out and forget how many filters there are, just by utilizing laws of thermodynamics, chemistry, and nucleosynthesis thst deter life ubiquitously.
Nah bro there is aliens.
I think _life_ might not be super-rare, but _intelligent_ life very well could be unique to this galaxy. Because some of the filters that might not be insurmountable for simple, unicellular life like bacteria, may well be insurmountable for more complex, multicellular life.
Why shouldn't we be caught up by the idea? The odds of Earth being the only planet with life on it in a Universe with trillions of planets are incredibly low, even after you filter out everything planetary type other than Earth-twins.
From what I can see, far more people are forgetting that "alien life" doesn't just mean little green men in spacecraft, but every form of life down to the simplest form of single-celled organisms, which didn't take very long to arise here on the primeval Earth, relatively speaking.
There's a vast ocean out there left to be explored, and we have yet to do more than dip our big toe in the water. No scientist is under the illusion that life exists under every rock, but the idea that there's no life of any kind anywhere else in the Universe is borderline nonsensical. The more we have discovered about the Universe, the less unique our own position in it becomes.
We’re either alone in the universe or not, and both possibilities are equally terrifying.
@@EnglishMike -- _"The more we have discovered about the Universe, the less unique our own position in it becomes."_
That's not true. Although we've discovered that solar systems with planets are much more common than previously thought, Earth appears increasingly unique among those planets as we learn about the contingencies required for life to arise--especially complex life.
For example, red dwarfs, which are several times more common than G2 stars like the Sun, have a liquid-water habitable zone that's close enough to the star to tidally lock the planets within the zone. This makes the front too warm for liquid water, the back too cold for liquid water, and a ring in the middle with perpetually extreme weather.
Additionally, the formation of the Moon was an incredibly unique event, with the impact that produced it involving the right combination of mass, velocity, and angle of impact to scrape or boil away almost all (but not actually all) of the Earth's water. (Otherwise, the planet would either by dry or locked beneath an ice layer like Matt explains at 15:30.)
thank you for continuing to do this series.
Being one of the first to PBS Space Time is a honour.
An* honour, indeed.
This is why the Dark Forest hypothesis falls apart. The aliens already know where we are, and soon, we will know where they are. In space, staying hidden is impossible.
In the 1993 point-and-click adventure game Star Trek: Judgement Rites, the final missions involved the crew of the Enterprise being tested by an alien species who identified themselves as the Brassica. Brassica is Latin for cabbage. The cabbage aliens have been foretold through computer games of old!
Oops -- someone didn't do their research. I once wrote a book where one of the main characters was a little alien girl called Pyria. I eventually looked up the word online only to find out it's another name for periodontitis, or gum disease. However, I liked the name too much to want to change it by then.
This is the best explanation of spectrography (absorption lines) I have seen for the layperson with an interest in science. Thanks again, Space Time.
Brilliant as usual. I think a lot of lay people crave to understand more about how we're 'seeing' characteristics with JWST and this does a nice job of briefly explaining how indirect measurements are used to calculate features.
I can watch this videos and still be amazed by science. love this series! there is still so much to learn! greetings from argentina! : )
Thank you so much for all these interesting explanations! It might have been useful to also explain why a molecule emits or absorbs IR light. To do so, the light changes the dipole moment of the molecule- causing it to wiggle in specific ways (its normal modes).
exploring and classifying exoplanets is so interesting
3500 Kelvin is my favorite lightbulb temp. I would love to live in a solar system with that kind of star.
Haha! Then you'd love that K2-18a. You'd feel right at home.
But not in a working room, there you need higher Kelvin.
Excellent video as always! Needed this today.
I love it when spacetime veers into chemistry and biochemistry.
Also, Hycean Planets is a great term.
Also also this detection "madness" reminds me of the Venus Hype a few years back; have there been any episode-worthy updates on that front (other than, "its not aliens", of course)?
What I like about this channel is that it only uses academically correct and precise language like fluffy stuff.
its hard to fathom how just how incredibly tiny that sample of light must be to come from a small, dim star which then passes through the sliver of atmosphere of an even smaller planet 100something lightyears away
I had not considered until he mentioned it, that it's only that relatively thin layer of atmosphere that is detectable regardless of the size of the planet.
Always eager to see how you fit in 'Space Time' into the outro XD
You should have a pre-order for that "Ok, it's aliens" T-shirt! 😂
Or maybe a cabbage aliens shirt :P
Below that it could read "IN YO FACE" 🤣
i don't think we ever will, i think we are all to far apart by space and time
ancient astronaut theorist, says yes.
keep up the good work Dr. Matt and team..
Saving this video. Greatm explanation on how we can tell such extraordinary things about planets so far away. Way better than me muddling my way through the basic concepts.
So what would aliens see if they looked at Earth's atmosphere from 100 light years away? Would they see DMS? Would they see all the molecules that would give them a 5 sigma that life exists here?
I hope someone knows the answer to this
No expert, but I think if they picked up the traces of CFCs in our atmosphere that might be a fairly good hint. Idk of any natural sources of such molecules, they are very definitely products of the laboratory.
(Of course, following the Montreal protocol CFCs have rapidly been depleted from the atmosphere. But from the perspective of an alien 50 lightyears away, that hasn't happened yet!)
yes
Depending on their tech level, yes. The most important would be oxygen, a gas that's rather tricky to produce in large amount abiotically. That and methane would be hard to ignore by themselves. DMS would be harder, our atmosphere's small and oxidizing, and probably wouldn't actually be necessary.
Interestingly things like CFCs present might even tip them off that we have industry.
@@garethdean6382 Agreed. High concentrations of oxygen should be the easiest indicator of photosynthesis and would be detectable out to at least 2 billion light years. Industrial indicators would only be visible out to 100-200 light years but that's an indicator of advanced life.
10:30 this gives a somewhat prophetic meaning to the 1981 French film starring Louis de Funès _"La Soupe aux Choux "_ ( _"The Cabbage Soup"_ ) 😉😳
An alien being attracted by Earthings eating (an metabolising 😜) cabbage soup.
Sometimes I wonder if intelligent life evolves on a planet with a high surface gravity, like 15g+, will ever be able to get into space. It would be terrible to be stuck at the bottom of a gravity well only being able to see space but never travel to it.
Hey, story of my life, too!
If they manage to split the atom, they would have enough energy available to do it.
Who knows, maybe the intelligent life form (the only life that would care about space) can find a way. Besides, that sounds like a 2D world.
@@donbruce8234 the planet in question is only 1.3g and super earths go up to about 3g but a surface gravity as above isn’t uncommon for larger planets, the highest surface gravity of an exoplanet we discovered is about 600g.
The planet here is only like 1.3g, but to answer your question more generally getting to space becomes exponentially harder with higher surface gravity. For example escaping 2g with standard hydrogen rockets would require them to be ~4 times more massive than the saturn V just to get into orbit (keep in mind the saturn V was built with mars in mind). Using nuclear rockets would help but you'd run into the same exponential barrier of impracticality eventually.
We're not looking for aliens we're looking for us on a different planet which makes finding other life forms even more difficult than it already is
Who's to say aliens won't discover us first, if not already.
Here’s the thing though. The first detection of life may well be even within our solar system. If there’s in fact a giant ocean that massively exceeds Earth’s, under a sheet of ice in Titan, and Saturn’s tog on Titan, as well as its residual core heat, is enough to sustain chemistry, it could well be home to life, but a very different type of life from one that lives on a planet’s surface, relying on energy from a nearby star.
I’m still fascinated that we can even detect lights that passed through the atmosphere of a plant at such distance…
I took a class called Super Earths and Life on Harvard EDX and learned all about this cool stuff. Fantastic science really.
And now you can honestly say that you are Harvard educated!
If we do end up finding aliens, I hope they are the friendly sort. Otherwise we could very easily be doomed.
Sometimes I feel like exobiology is like being a Skyrim guard.
An alien slaps you in the face: "Who's walking there?!"
You explain away your own observation: "Must have been the wind..."
On the other hand, no dragons have popped up recently to set fire to our houses. With something so big you really do want to be sure. We've embarrassed ourselves too many times before, jumping the gun.
If most sigma 1 detections are false positives, shouldn't the rate of errors be more than 50% rather than 30 something?
Statistics is weird, but Astronomy and physics in particular is really stringent. Regardless, a 1 Sigma detection is enough to warrant further study.
@@ratking1330 I didn’t say it didn’t warrant study. I wouldn’t know. My question is because I’m confused by 32% resulting in “most” sigma 1 results being false positives. I was hoping someone could explain further so I could understand at least a bit more.
IF everyone was honest and unbiased and logical, then 1 in 3 sigma-1 results would be wrong.
HOWEVER, scientists are motivated to report unusual results, to HAVE a result to write a paper on. They want to succeed and often have multiple ways to analyze data to ensure that they can claim a result. As such many sigma-1 results are, if not fraudulent, then biased. And as such many fail when scrutinized.
But sigma-1 isn't an average success over time, it's a mathematical definition. It MUST have a failure rate of 33%. The higher rate comes from people using it incorrectly. Extra-virgin olive oil is still a thing, even though most of it is faked. So the 'true' failure rate of anything is higher than what might be expected from pure honest math.it's unfortunate but true, a sort of 'nobody talks about it' thing in the sciences.
That "32% chance" has nothing to do with the true chance (this is one of the common misconceptions of statistical hypothesis testing, due to the weird way "significance" is defined.)
What it means is that assuming there really is no DMS, we'd only expect the observed results 32% or more of the time. Meaning that the results could be caused by noise 32% of the time. Note that it isn't saying anything about the true probability of an event, rather just how unlikely it was to happen by chance *this one time* (with enough trials, you can still run into rare chance events.) And when the underlying event is super rare (like DMS occurrence probably is), then most DMS detections will be false positives.
To demonstrate the above: An analogy I like to make is with rare diseases. You can use Bayes' Theorem to calculate the probability of having a rare disease given that you tested positive. If the false positive rate (AKA the probability you receive a positive given that you didn't have the disease) is low but the frequency of the disease in the population is much lower, then the probability of having the disease after receiving a positive is also low. That's because there will be way more false positives than actual disease patients, since the probability of a false positive-while low-is still much higher than the general population occurrence rate of the rare disease.
@@theduckster01 Thank you!
The ok it was aliens tshirt is gonna go so hard, can’t wait
I, for one, welcome our new cabbage overlords
John Oliver is way ahead of us on this; he married one.
David Grusch, David Fravor, Ryan Graves
Edit: apparently, I know nothing. Yeah, a hydrogen atmosphere should be fine.
------
I'm just a dude with a B.S. in atmospheric / oceanic science and an interest in astronomy.
That being said, I'm pretty sure a hydrogen atmosphere would diffuse into a liquid water ocean and cause it to become _extremely_ acidic, meaning just about all you'd see would be extremophile bacteria. A hydrogen atmosphere seems bad for life, but what do I know.
While acidity itself doesn't influence density, it can influence external factors that can change the density of a fluid. There's would likely be pockets of less acidic and more acidic water. It's not quite as much as a deal breaker as it seems
@@ratking1330 on a planetary scale, sure, differing pockets could form due to rising or sinking action in the atmosphere or due to sequestration into rocks, but... with an atmosphere that is so highly composed of hydrogen, over the course of millions of years, even assuming little to no mixing, the hydrogen would diffuse even into the deep ocean.
And such an ocean probably would produce some molecules we don't see here...like DMS.Hycean worlds may be false positive factories.
I'm not sure I get you; hydrogen is pretty neutral, is it not? it doesn't dissociate much in solution so where would the acidity come from? I know H- isn't stable in water, it produces OH- and hydrogen, so I"m not sure where you'd get a source of unbalanced H+ from.
I think the bigger issue would be if the rock was cut off from the water, leaving you with a very nutrient-poor ocean.
So interesting that intelligent life ended up developing on land and not water
I would say that we already have… it’s just very well covered up and kept from us.. has been for more than 80years
So we need a new equation for the probability of life becoming intelligent, discovering a branch of science that leads to interstellar travel, and also factir in evolving to recognize the value of maintaining diversity.
Then, add in its range of influence and ability to constrain less advanced life that would try to colonize everything and destroy us.
So that would give the probability of discovering other life that's already here.
But one has to also take account of the probability that small groups of oligarchs have propagated disinformation and maintained a cover up, then this becomes revealed.
Oh, wait a minute, isn't this just what's happening?
A premise of "2001" and many other sci-fis was that there would be widespread alarm if the discovery of the extraterrestrial life was announced publicly.
And yet for nearly 200 years, going back to the New York Sun "Moon Hoax" in 1835, the reaction to numerous pronouncements of life detected elsewhere has generally been only mild and fleeting interest.
We like to think that we're poetic.That we'd appreciate life off Earth for its deep philosophical meaning, for the perspective it would give us on our place in the universe. Or that,in tragic irony, we would recoil in horror and scour the knowledge from our world with fire.
But we're dull. Looking for the newest shiny thing. A war headlines for a week, a nuclear catastrophe is soon buried beneath celebrity gossip. Our banality is perhaps the truth we fear to face.
Alien scout vessel: "Sir we have located a class M planet. Sentient life forms and structures detected, but they don't pass the intelligence test I'm afraid. They are destroying their own ecosystem willingly due to something called "money"
Alien Captain: "That's a shame.... Well lets move on to another system and leave these doomed fools alone."
Hmm it cut out the -or on water vapor. Dunno if it's an error during editing or a noise-gate issue. Otherwise, lovely video and I can't wait for more!
"atmosphere" at 5:31 has a weird stretch like it's a separate cut.
Thanks for telling me about Hycean planets!
I love this channel
I have notifications for this channel set to all but I am not receiving notifications. This episode just appeared randomly in my feed after refreshing a few times.
@5:30 “atmospherrrrrrrre” Leaning into that one for the viewers from North America, or various counties in rural England,
I’ve been writing about similar topic cool to see others flipping through similar pages
What I have specifically not heard concerning alien life is that it is possible that *we* are the advanced alien civilization that we always assume some other entity would be. We may simply be that alien life before it has advanced enough to jump around the galaxy. We may be the most advanced life in the galaxy or even the universe and the truth is that our greatest grandchildren may be the aliens other future life dreams of like we are doing now. Who knows?
0:45 - Well, we don't have a solid explanation for "Wow!" signal. Doesn't mean it was an alien tight beam communication signal strafing us accidentally, but it is not anything equivalent to the signal that marked the discovery of pulsars. We will probably never know.
When we do discover 5-sigma evidence of alien life (hopefully in my lifetime!), I expect that PBS SpaceTime merch will have that t-shirt!
Rather than "Grey humanoid with big eyes 👽 " i bet the first extraterrestrial we encounter just a single cell organism like a bacteria but from other planet like Mars or from Moon like Titan.
08:03 unless he told "water-vape", the audio still over complessed, and hurting the product!
they need to pay money for an audio director, the audio editing is still waaaay worse than it was year ago
brb, going to rush to buy an expensive bottle of champagne for when JWST actually does indeed find aliens
Can we at least get the “it might not not be aliens T-shirt?”
K218B is not fluffy, it’s just big cored.
I would LOVE an "okay its aliens" t-shirt😂
Nice presentation!
i have to imagine that once we find the first planet with life, we will go, "OH, we needed to reconfigure the thingamabob to capture the sub spectra, etc, etc....." and then we will be finding life all over (though still a very small % of all planets).
*flux capacitor 🤣⛳
Now my wife keeps calling me a little Neptune.
Actually, oumuamua isn't technically explained yet by the scientific community at large. So the hypothesis that oumuamua is a probe of some kind sent by aliens is still valid
"A reason not to be not excited..." - gold 🙂
Humanity should build its ideas and life that there are indeed living beings like him in some way in the depths of the universe, even if he will not reach them and will not see them, this is the right logic to touch the facts with.
great video as usual and I like the outro music 😍
The scene from Dumb and Dumber pops in my head ... "So you're saying I have a chance!"
Love the 80’s transitions!!!😊
can't wait to wear that shirt! just ordered my own!
Spacetime curved around my mouse forcing me to refresh UA-cam at the exact picosecond this video was uploaded!
If I could time travel, I’d go find Johannesburg Kepler, and show him this video, along with a short explained about what atoms and molecules are, and what the electromagnetic spectrum is, etc. I’d give him those explainers first, then show this video, and then say thanks for your contributions.
And just as I was rolling my eyes and ready to click to the next video..😂
Finally, an episode that I can follow 😊
We live in a relatively young universe and there is a greater possibility that we are the first inter galactic or could be the first inter galactic species in this universe. If there was any advance civilisation millions of years ahead of us , they would have definitely contacted us or atleast there would have been some kind of evidence related to them . I am sure that life and an advanced life like multicellular organisms or some intellectual species is not that easy to originate.
Really fascinating observation, but not likely aliens
10:38
The promoter of the Miss Stardust pageant begs to differ.
Imagine probing the universe for aliens and it's like "yay we found them" but then it's just like a bunch of bacteria
I'm in that camp. If we do find alien life, it's most likely to be bacterial or something microscopic that can survive harsh conditions.
I remember years ago there was a major report about scientists possibly finding fossils or remnants of microbes in a meteor or something. I was super excited but then I heard nothing for many years. The next time I heard anything about it, it was on PBS SpaceTime and Dr. O'Dowd explained what happened. I was glad I finally found out what happened, but also a little sad because...it wasn't aliens. It was still good to know though.