How Will We (Most Likely) Discover Alien Life?
Переглядів 584,748
6 місяців томуPBS Member Stations rely on viewers like you. To support your local station, go to:to.pbs.org/DonateSPACE
Sign Up on Patreon to get access to the Space Time Discord!
/ pbsspacetime
The first discovery of extraterrestrial life will almost certainly NOT be when it visits us, nor when we visit it. It won’t be when we see it’s stray TV signals. It’ll be in the excruciatingly faint changes in the color of alien sunsets glimpsed hundreds of light years away. Today we’re going to talk about the first such hint, why it's probably not aliens, and why there’s a tiny chance that it still might not not be aliens.
Check out the Space Time Merch Store
www.pbsspacetime.com/shop
Sign up for the mailing list to get episode notifications and hear special announcements!
mailchi.mp/1a6eb8f2717d/space...
Search the Entire Space Time Library Here: search.pbsspacetime.com/
Hosted by Matt O'Dowd
Written by Matt Caplan & Matt O'Dowd
Post Production by Leonardo Scholzer, Yago Ballarini & Stephanie Faria
Directed by Andrew Kornhaber
Associate Producer: Bahar Gholipour
Executive Producers: Eric Brown & Andrew Kornhaber
Executive in Charge for PBS: Maribel Lopez
Director of Programming for PBS: Gabrielle Ewing
Assistant Director of Programming for PBS: John Campbell
Spacetime is produced by Kornhaber Brown for PBS Digital Studios.
This program is produced by Kornhaber Brown, which is solely responsible for its content.
© 2023 PBS. All rights reserved.
End Credits Music by J.R.S. Schattenberg: / multidroideka
Space Time Was Made Possible In Part By:
Big Bang Sponsors
Bryce Fort
Peter Barrett
David Neumann
Sean Maddox
Alexander Tamas
Morgan Hough
Juan Benet
Vinnie Falco
Fabrice Eap
Mark Rosenthal
Quasar Sponsors
Glenn Sugden
Alex Kern
Ethan Cohen
Stephen Wilcox
Mark Heising
Hypernova Sponsors
Stephen Spidle
Chris Webb
Ivari Tölp
Zachary Wilson
Kenneth See
Gregory Forfa
Bradley Voorhees
Scott Gorlick
Paul Stehr-Green
Ben Delo
Scott Gray
Антон Кочков
Robert Ilardi
John R. Slavik
Donal Botkin
Edmund Fokschaner
Chuck Zegar
Jordan Young
Daniel Muzquiz
Gamma Ray Burst
Billy Holland
Leonardo Schulthais Senna
Lori Ferris
James Sadler
Dennis Van Hoof
Koen Wilde
Nicolas Katsantonis
Piotr Sarnicki
Massimiliano Pala
Thomas Nielson
Joe Pavlovic
Justin Lloyd
Chuck Lukaszewski
Cole B Combs
Andrea Galvagni
Jerry Thomas
Nikhil Sharma
Ryan Moser
John Anderson
David Giltinan
Scott Hannum
Bradley Ulis
Craig Falls
Kane Holbrook
Ross Story
teng guo
Mason Dillon
Matt Langford
Harsh Khandhadia
Susan Albee
Matt Quinn
Michael Lev
Terje Vold
James Trimmier
comboy
Jeremy Soller
Paul Wood
Joe Moreira
Kent Durham
Jim Bartosh
Ramon Nogueira
John H. Austin, Jr.
Diana S Poljar
Faraz Khan
Almog Cohen
Daniel Jennings
Russ Creech
Jeremy Reed
David Johnston
Michael Barton
Isaac Suttell
Oliver Flanagan
Bleys Goodson
Mark Delagasse
Mark Daniel Cohen
Shane Calimlim
Tybie Fitzhugh
Eric Kiebler
Craig Stonaha
Frederic Simon
John Robinson
Jim Hudson
Alex Gan
David Barnholdt
John Funai
Bradley Jenkins
Vlad Shipulin
Cody Brumfield
Thomas Dougherty
King Zeckendorff
Dan Warren
Joseph Salomone
Patrick Sutton
Dean Faulk
@gregspecht481 6 місяців тому
everybody gangsta until its actually aliens
@k7crusader 6 місяців тому
Dude your comment LITERALLY made me fart rapidly at my girlfriend's face
@JK7H 6 місяців тому
@@k7crusader bullshit, you ain't got no girlfriend
@k7crusader 6 місяців тому
@@JK7H yeah yeah okay dude how about YOU let one loose in my face? I'll pay you
@energetic479 6 місяців тому
@@JK7Hyeah not with that pfp
@RFDN0 6 місяців тому
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.
@rlosable 6 місяців тому
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.
@toosas 6 місяців тому
sorry to hear that he did not make it to see it but great that you have!
@MicahTischler 6 місяців тому
Sorry for your loss, but I hope you're managing to enjoy a non-vengeful posthumous told-you-so. :)
@hugegamer5988 6 місяців тому
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.
@rlosable 6 місяців тому
@@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!
@KeithCooper-Albuquerque 6 місяців тому
@@rlosable Yours was a wonderful reminisce that I'm sure you'll treasure always. Thanks for sharing this bittersweet moment! Peace.
@Kahnabys 6 місяців тому
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.
@FLPhotoCatcher 6 місяців тому
That was partly due to the Protestant work ethic.
@erik-ic3tp 5 місяців тому
@@FLPhotoCatcher, how? Because pleasure/leisure is frowned upon by Protestantism/Calvinism?
@FLPhotoCatcher 5 місяців тому
@@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.
@tomc.5704 5 місяців тому
@@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
@Xorphial 5 місяців тому
@@FLPhotoCatcher absolute bullshit.
@ariesmars29 6 місяців тому
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."
@alexpotts6520 6 місяців тому
This is just the old God-of-the-gaps fallacy updated for the 21st century.
@mahadevparmekar2565 6 місяців тому
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.
@tym6245 6 місяців тому
Things are unprecedented, until there not .
@LuisSierra42 6 місяців тому
I have to confess that I am an extraterrestrial
@tamarinds 6 місяців тому
its aliens
@TheScourge007 6 місяців тому
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."
@EnglishMike 6 місяців тому
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.
@WilliamFord972 6 місяців тому
Oh, that’s good.
@jamesrivera4535 6 місяців тому
Long time watcher. I just to say thank you for always being truthful about the tentativeness of discoveries. So many UKposts 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.
@thomascaldwell184 6 місяців тому
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.
@LuisSierra42 6 місяців тому
Is Matt retiring?
@thomascaldwell184 6 місяців тому
@@LuisSierra42 No-- or at least, not that I know of. I just want to make sure that always remains the case. ;-)
@R.T.and.J 5 місяців тому
>inb4 Futurama heads in a jar
@MagesIncorporated 5 місяців тому
>inb4 GenAI replication
@ericmatthews8497 6 місяців тому
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.
@dembro27 6 місяців тому
Agreed. We'll have to move to... DOUBLE letters...
@EnglishMike 6 місяців тому
They're already using full names to describe planetary types, so I don't think that will be an issue!
@geno4526 6 місяців тому
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.
@ObjectsInMotion 6 місяців тому
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
@der.Schtefan 6 місяців тому
26 main classes for the most important, or safe to visit, ones, and as many subclasses as you want
@sharky582 6 місяців тому
What scifi movies will Matt watch this week? I'm not sure, all I know is - it's never Aliens...
@punkiller666 6 місяців тому
Alien: Resurrection, maybe!
@thangs 6 місяців тому
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.
@johnmorrell3187 6 місяців тому
Happy birthday!
@ashtyler8 6 місяців тому
Happy Birthday. Just remember, 50 is like 20, but just 30 more.
@thangs 6 місяців тому
@@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. :)
@walterfristoe4643 6 місяців тому
Every time I use the word "coincidental" I get accused of being an anti-dentite! 🤣🦷
@manuelhernandez2017 6 місяців тому
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!!!!
@donald-parker 6 місяців тому
I wonder how detectable life on earth would be from such a distance.
@EnglishMike 6 місяців тому
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.
@themice42 6 місяців тому
with the amount of pollution we produce, using these techniques, probably along the lines - POO I don't want to go there!
@567secret 6 місяців тому
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.
@KeithCooper-Albuquerque 6 місяців тому
I'm sure the aliens can smell us from there ...
@mrsensei8878 6 місяців тому
@@567secret They wouldnt see that, they will see the earth 124 years ago.
@peters616 6 місяців тому
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.
@Jobobn1998 6 місяців тому
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 5 місяців тому
What if we launch only 1 more and ALSO add universal healthcare? Or is that scenario as likely as life on any individual exoplanet? 😉
@Jobobn1998 5 місяців тому
@@Rebel7284Nah, the universal healthcare can be payed by taxing billionaires. :P
@slimee8841 6 місяців тому
Now sci-fi writers can write "cabbage aliens" into their words and claim some scientific accuracy, amazing
@dembro27 6 місяців тому
It's the Invasion of the Brassicans! 😱
@moosemaimer 6 місяців тому
"What, you think I'm not detectable, just because I have a CABBAGE FOR A HEAD?"
@jamesrussell7760 6 місяців тому
Move over "cone heads". We need some room for "cabbage heads"!
@M4xFr4gg 6 місяців тому
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.
@nishgriff1 6 місяців тому
thank you for continuing to do this series.
@MatthewTheWanderer 6 місяців тому
Actually discovering alien life would be easily one of the coolest things to ever happen!
@trailingupwards 4 місяці тому
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.
@The1stDukeDroklar 4 місяці тому
And potentially the most scary thing to ever happen.
@Ofinfinitejest 6 місяців тому
"It's Usually Human Delusions" - Would be the most truthful T-shirt.
@jacobkrebs7248 6 місяців тому
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.
@robbirose7032 6 місяців тому
Nah bro there is aliens.
@MarsJenkar 6 місяців тому
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.
@EnglishMike 6 місяців тому
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.
@WilliamFord972 6 місяців тому
We’re either alone in the universe or not, and both possibilities are equally terrifying.
@mvmlego1212 6 місяців тому
@@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.)
@Zahlenteufel1 6 місяців тому
If I learned one thing on this channel it's that ✨it's never aliens until it's aliens ✨
@olafsigursons 6 місяців тому
It will never be alien. They don't want to find it.
@Wopple 6 місяців тому
Never aliens!
@onedeadsaint 6 місяців тому
@@olafsigursons lol
@EnglishMike 6 місяців тому
@@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.
@hugegamer5988 6 місяців тому
Let’s hope it’s not, they will eventually get our TV broadcasts of salad commercials.
@mk1st 6 місяців тому
As a certain Vulcan would say: Fascinating
@marklee1462 6 місяців тому
Honestly this is exactly and solely what just should be focused on investigating planets in Goldilocks zone. This was a fantastic episode
@GettheFouttahere74 5 місяців тому
I would say that we already have… it’s just very well covered up and kept from us.. has been for more than 80years
@PratiwiSr-sv6qp 4 місяці тому
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?
@crowlsyong 4 місяці тому
Matt and the PBS Spacetime team have brought joy and wonder to my life. Thank you.
@seantlewis376 5 місяців тому
This is the best explanation of spectrography (absorption lines) I have seen for the layperson with an interest in science. Thanks again, Space Time.
@1990erre 6 місяців тому
The talk of ocean worlds makes me excited to play Stellaris again. I can highly recommend it if you like Civilization games.
@thegreatbigmulp 6 місяців тому
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!
@EnglishMike 6 місяців тому
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.
@aceofdatabase 5 місяців тому
Excellent video as always! Needed this today.
@dashvash5440 3 місяці тому
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.
@meinbherpieg4723 6 місяців тому
Your educational brilliance is a blessing to the world. Thank you for everything you have done all these years. I will never stop watching.
@michaelmargreiter2964 6 місяців тому
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).
@agargamer6759 6 місяців тому
Thanks for telling me about Hycean planets!
@rogermeyersjr 6 місяців тому
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.
@LuisSierra42 6 місяців тому
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
@skycloud4802 6 місяців тому
I didn't like Gabe's style, without disrespect. I think Matt is a much better fit for space-time.
@jatzi1526 6 місяців тому
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
@FatherDragonKal 4 місяці тому
Gabe had a lot of passion for the science and without him SpaceTime wouldn’t be where it is today
@dianagibbs3550 6 місяців тому
"...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...
@housellama 6 місяців тому
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.
@garethdean6382 6 місяців тому
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.
@allanburns1190 6 місяців тому
I wake up every morning and check my phone to see if pbs space time has posted
@SirAlanClive 6 місяців тому
Nice episode. Had me riveted.
@KeithCooper-Albuquerque 6 місяців тому
Thanks Matt and team for another great video! These are indeed exciting times!
@jajssblue 6 місяців тому
You should have a pre-order for that "Ok, it's aliens" T-shirt! 😂
@R.T.and.J 5 місяців тому
Or maybe a cabbage aliens shirt :P
@The1stDukeDroklar 4 місяці тому
Below that it could read "IN YO FACE" 🤣
@Jagzeplin 6 місяців тому
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
@The1stDukeDroklar 4 місяці тому
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.
@zakariferguson2155 6 місяців тому
Always eager to see how you fit in 'Space Time' into the outro XD
@sabotagesabotage7927 6 місяців тому
I’ve been writing about similar topic cool to see others flipping through similar pages
@matthewguski5942 6 місяців тому
3500 Kelvin is my favorite lightbulb temp. I would love to live in a solar system with that kind of star.
@ashtyler8 6 місяців тому
Haha! Then you'd love that K2-18a. You'd feel right at home.
@vast634 5 місяців тому
But not in a working room, there you need higher Kelvin.
@Biomirth 6 місяців тому
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.
@robcat2075 6 місяців тому
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.
@garethdean6382 6 місяців тому
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.
@obamtl 5 місяців тому
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.
@TaylorFalk21 6 місяців тому
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?
@rockw300i 6 місяців тому
I hope someone knows the answer to this
@alexpotts6520 6 місяців тому
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!)
@user-ey2xp2ge9y 6 місяців тому
yes
@garethdean6382 6 місяців тому
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.
@The1stDukeDroklar 4 місяці тому
@@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.
@hugegamer5988 6 місяців тому
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.
@unvergebeneid 6 місяців тому
Hey, story of my life, too!
@EnglishMike 6 місяців тому
If they manage to split the atom, they would have enough energy available to do it.
@donbruce8234 6 місяців тому
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.
@hugegamer5988 6 місяців тому
@@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.
@Morgan-rh3rc 6 місяців тому
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.
@MrRoboticBrain 6 місяців тому
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..."
@garethdean6382 6 місяців тому
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.
@ScruffR70 6 місяців тому
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.
@iainmackley 6 місяців тому
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)?
@n0madfernan257 6 місяців тому
ancient astronaut theorist, says yes. keep up the good work Dr. Matt and team..
@GS-el8ll 4 місяці тому
exploring and classifying exoplanets is so interesting
@user-eo3bm9sg7n 6 місяців тому
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.
@DennisBratland 6 місяців тому
If most sigma 1 detections are false positives, shouldn't the rate of errors be more than 50% rather than 30 something?
@ratking1330 6 місяців тому
Statistics is weird, but Astronomy and physics in particular is really stringent. Regardless, a 1 Sigma detection is enough to warrant further study.
@DennisBratland 6 місяців тому
@@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.
@garethdean6382 6 місяців тому
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.
@theduckster01 6 місяців тому
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.
@DennisBratland 6 місяців тому
@@theduckster01 Thank you!
@yourma2000 5 місяців тому
Who's to say aliens won't discover us first, if not already.
@onedeadsaint 6 місяців тому
can't wait to wear that shirt! just ordered my own!
@patrickhoward3892 Місяць тому
One - HOW do we measure the 'dopler-shift' in a spectrum of light? - And two - wouldn't that make it possible to see how far light has travelled, and we can get an accurate 'shape' of the observable universe?
@sunnyscaper8560 6 місяців тому
I’m still fascinated that we can even detect lights that passed through the atmosphere of a plant at such distance…
@arthurmartin4616 6 місяців тому
If we do end up finding aliens, I hope they are the friendly sort. Otherwise we could very easily be doomed.
@helloyes2288 6 місяців тому
@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.
@edin2934 6 місяців тому
Finally, an episode that I can follow 😊
@philipmurphy2 6 місяців тому
Being one of the first to PBS Space Time is a honour.
@genghisgalahad8465 6 місяців тому
An* honour, indeed.
@bifflowman2948 6 місяців тому
I, for one, welcome our new cabbage overlords
@WindsorMason 6 місяців тому
John Oliver is way ahead of us on this; he married one.
@mvsmvs8428 6 місяців тому
i don't think we ever will, i think we are all to far apart by space and time
@ihsansalh3622 6 місяців тому
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.
@Sushiman118 6 місяців тому
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.
@ratking1330 6 місяців тому
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
@Sushiman118 6 місяців тому
@@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.
@naamadossantossilva4736 6 місяців тому
And such an ocean probably would produce some molecules we don't see here...like DMS.Hycean worlds may be false positive factories.
@garethdean6382 6 місяців тому
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.
@Simp_Zone 6 місяців тому
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."
@abysmalasabysmal 6 місяців тому
I took a class called Super Earths and Life on Harvard EDX and learned all about this cool stuff. Fantastic science really.
@Oberon4278 6 місяців тому
And now you can honestly say that you are Harvard educated!
@Jean-jk4zv 6 місяців тому
great video as usual and I like the outro music 😍
@frankharr9466 6 місяців тому
Wonderfully detailed. Thank you.
@gavinjones 5 місяців тому
I like how near the end, the significance of finding aliens was turned into just another thing to sell merch about
@bahamuttg 6 місяців тому
Love the 80’s transitions!!!😊
@grokeffer6226 6 місяців тому
Fascinating and logical, too. 👽🖖
@Numba003 6 місяців тому
Thank you guys for another excellent exoplanet video! I remember reading about some of this info a few weeks ago. This is such an exciting time to be alive in terms of astronomy! Deciphering planetary atmospheres from light years away is miraculously beautiful, and I greatly look forward to all the discoveries ahead. God be with you out there everybody. ✝️ :)
@Nick77ab2 6 місяців тому
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!
@ripvanwando 6 місяців тому
"atmosphere" at 5:31 has a weird stretch like it's a separate cut.
@ErikBongers 6 місяців тому
What I like about this channel is that it only uses academically correct and precise language like fluffy stuff.
@m_sedziwoj 6 місяців тому
And we must remember about weather. Water volcano and Hubble's data are good, so so more observation would be great.
@Phlegethon 6 місяців тому
Great thumbnail art those always look so cool
@OslerWannabe 5 місяців тому
From my 1971 chemistry B.S., I have a vague recollection that Mee-thane degrades to Meth-ane. On Earth, this generally happens to Mee-thane during transport from Commonwealth countries to the western hemisphere, if it is transported in Aluminium tanks. The catalysis occurs at the inner surface of the tank, producing Aluminum. Through the loss of one Iodine atom, I, as I seem to recall. Something like that. My recollection is a bit fuzzy, since the TA of my senior organometallics class was a really cute young woman, and I was done working hard, having already been accepted into medical school. As had she, it turns out, same school, same class -- we ended up classmates. Chemistry can be incomprehensible like that.
@bazoo513 6 місяців тому
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.
@SmogandBlack 6 місяців тому
Very good, as always... 😊
@fraliexb 6 місяців тому
Why does every scientist only mention "Goldilocks zone" when it comes to liquid water, but geothermic energy can create liquid water outside the "Goldilocks zone." Also how close to the Roche Limit is K2-18a's planets?
@garethdean6382 6 місяців тому
Because it's a useful approximation; without it, almost any planet COULD have liquid water on it, somewhere, somehow. Those are planets that need a special reason to have water. A Goldilocks planet is one where there needs to be a special reason there ISN'T water. We focus on them because we believe them to have the highest chance of life. We can't look everywhere all at once, w need some criteria to start. K2-18A's planets are between 20 and 80x the Roche limit from their star, they're in no danger of being torn apart.
@pixartist8190 6 місяців тому
Hey this is very interesting but I wish we would get a bit more content in the direction of physics and developments in quantum gravity
@gorkemvids4839 6 місяців тому
Question: When universe was cooling, temprature dropped to 100-0 centigrates for a time lenght. Kurzgesagt claimed life might started in this era. Please explain this posibility. Thanks.
@artificercreator 6 місяців тому
Nice presentation!
@rgarbacz 6 місяців тому
"A reason not to be not excited..." - gold 🙂
@michaelteegarden4116 4 місяці тому
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!
@Molatov_Cockatiel 6 місяців тому
@5:30 “atmospherrrrrrrre” Leaning into that one for the viewers from North America, or various counties in rural England,
@seraeirian2 6 місяців тому
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).
@_chipin 6 місяців тому
*flux capacitor 🤣⛳
@ChristianKetterer6776 6 місяців тому
Excellent video. Vert clear.
@uruuruis 6 місяців тому
Lern to whrite, you dunb!
@gerakore8948 6 місяців тому
wavelet transform would be great for this
@juanisimocr3813 6 місяців тому
brb, going to rush to buy an expensive bottle of champagne for when JWST actually does indeed find aliens
@Gabriele1979 6 місяців тому
fascinating
@benlltt 6 місяців тому
The ok it was aliens tshirt is gonna go so hard, can’t wait
@BronzeRivet 6 місяців тому
5:31 atmospherrrrrrrrrrrr decrescendo.
@JoeVanGogh 6 місяців тому
I would LOVE an "okay its aliens" t-shirt😂
@NewMessage 6 місяців тому
10:38 The promoter of the Miss Stardust pageant begs to differ.
@remiesmith7027 6 місяців тому
I'd love to hear your thoughts on Kurzgesagt's recent video which posits that life itself is as nearly old as the universe. In that case the origin of life on K2-18b would be out of the picture. I also wonder, in the case of a more even mix between atmosphere and ocean, would there still necessarily be an ice layer around the rocky interior?
@MarcdeSaint 6 місяців тому
Beautiful
@stevesmith4600 6 місяців тому
The scene from Dumb and Dumber pops in my head ... "So you're saying I have a chance!"
@maddyfighter7881 4 місяці тому
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.
Filmegator
Переглядів 815 тис.
Осторожно: Собчак
Переглядів 6 млн
Scott Manley
Переглядів 137 тис.
PBS Space Time
Переглядів 1,5 млн
StarTalk
Переглядів 436 тис.
Filmegator
Переглядів 815 тис.