A two-fabulous figure, our best figure of the night. Oh, wow, big claims. You can decide at the end of the night. Please welcome Dr. James Davenport, research scientist at the University of Washington. Woo! Woo! He's a strong man on tap. Seattle's premier tent-based science outreach activity. Astronomers hate this one weird trick. Seven tips to reduce your gray matter fat. Insert other clickbait titles. You've seen them. I've seen them. We're going to talk about them. And because I feel like I'm here with 100 of my closest friends, I want to give this talk on a personal note. This is something that I haven't really talked about before. So come along with me on this journey. Be a little forgiving as I kind of explore this thing that's been sort of bothering me. And I want to get it off my chest. And I want to talk to you about this. But before we dive in, I want to set some ground rules for what I'm going to say and what I'm not going to say. And the first thing I want to say is, thank you for coming out. Thank you for supporting science, local scientists, local business, local beer, local vegan hot dogs. And thank you for supporting knowledge and truth in a time when we really need more of that. Thank you. Give yourself a round of applause for that. Woo! OK, good cheesy audience interaction check. Next. OK, the first thing I want to say is, am I open this way? OK, there we go. The first thing I want to say is, I am a huge fan of science. I love, yes, I love science. There's a reason that I do this for a living. And it's not the pay. And it's not the glamorous office. Though UW is a lovely campus, you should all visit.  It's awesome. I love, every time I see in the news, cool headlines, amazing graphs. I love that graphs become part of our narrative and part of our news media. It's an exciting time to be a fan of science, to be part of the sort of cultural movement that appreciates knowledge and certain truth. Thumbs up science. OK, so first, I love science just like you. I'm a fan of science. The second thing, which I think is actually just restating the first thing, is that when you're a scientist or when you're a fan of science, you love failure. You love being wrong. Being wrong is just nature telling you that don't try again. Come up with a better idea, a better explanation for how the universe is working. So if you love science, you have to love the struggle. And you have to love truth. OK, truth. And that's what this talk is about. It's about rooting out the BS and discovering the truth and appreciating and celebrating the truth. Being wrong is OK. I'm going to talk about clickbait articles and headlines that didn't turn out to be true or were overexaggerated and more pictures that were like, oh, that was photoshopped.  So we're not here to dunk on people who are just enthusiastic. We're here to help get everybody on team truth, team root out the BS. So being wrong is OK. Let's move forward from there. So with those ground rules in place, come with me as we talk about clickbait, misunderstandings, and maybe even some outright lies. The first example I want to talk about is one that started many years ago, something like almost 20 years ago, which is this so-called the Mars hoax. I'm sure people have seen this in their inbox with forward, forward, read, forward. Go outside and see Mars. It's going to be the size of a ham sandwich in the sky. I've seen this email repeatedly over the years. This is called the Mars hoax. He even has his own Wikipedia page called Mars underscore hoax. And it tends to crop up every August. Sometime in late August, usually August 25th or 27th, something like that. And the claim is that go outside, because Mars is going to be so big in the sky that it'll be giant, and it'll be awe-inspiring, and it'll be as big as the moon, or as big as, again, a ham sandwich or something. I don't know. It'll be huge. It'll be spectacular. It'll be the last time in 40,000 years that you'll see it. And you've got to go outside.   And then you're disappointed.  There's a reason I didn't do this in college. And you move on. And little by little, we chip away at your interest and your excitement and your enthusiasm and your belief and your trust in science as an institution. The funny thing about this hoax is that it was based largely on the truth. Is that about 20 years ago, there was a time when Mars was the closest it had been in 40,000 years. It was slightly closer than it usually is, which made no perceptible difference whatsoever. Mars just looked like a dot. You go outside and it's like, yep, it's that one? And that was Mars at its closest opposition. And it was cool. And Hubble, I think, actually even took this photo, the Hubble Space Telescope, actually took this photo at that point because it was slightly closer. I think it was cool. But this has morphed and recurred because it's so spectacular and ridiculous. OK. Here's another great one that I see a lot. Any time there's an eclipse, any kind of eclipse, really, you see this thing floating around Reddit and Twitter.  Wow. And it's awesome. But that's just objectively awesome looking. There's the Milky Way, and there's a shadow, and there's contrasts and colors. And this is somebody's work from ARC website, DeviantArt. This is somebody's Photoshop where they were trying to show off cool stuff. This was not meant to deceive you. It was meant to be like, hey, look at my Photoshop skills. And instead, it's been co-opted into this hoax about, like, this amazing picture has only been seen by astronauts eating ham sandwiches once in 40,000 years. And it's nonsense, right? This is not what an eclipse space looks like, and you wouldn't see the Milky Way. But the enthusiasm is good, right? That's the point. People aren't sharing this because they're trying to get you to buy something. They're sharing it because space is cool. And science is cool. But I've hit like on this before, and then be like, ah, damn it, this is the Photoshop one, right? Eclipse from space. OK, the third one that I want to talk about right here is the Super Blood Wolf Coyote Moon thing. We did have some amazing eclipses, some amazing, this was from space.com, but some amazing eclipses. This is all good. I'm happy here. I don't love the title. I don't know what a blood wolf moon is or what makes it super, but like I'm fine. Go outside, watch the eclipses, cool. It's amazing. Take a picture. It's great. This is fine. This is a problem. This is Rio de Janeiro plus, I don't know, like a Ridley Scott movie.  You're like, what? What? Right, you can go, I mean, this should tell you this is a problem because it's even on Snopes, right? There are BS websites, Snopes.com, the Super Moon nonsense. This is a problem. OK, the point of part one of this talk is science communication is important. We got to communicate what's true. This is a great headline from Ironically.  They retweeted, this is yesterday. I took the screenshot, so it's 15 minutes plus 24 hours. Millions of Americans think chocolate milk comes from? Brown cows. Come on, what? No, that's not true. I don't think so. The survey that they link to says 7% of adults in America think chocolate milk, this is not a astronomy for all those playing along, this is just milk, 7% of adults in America think that cows produce chocolate milk. And what's funny about it is also the survey was kind of garbage, like if you go back and look at the survey, they did do a survey, but the survey is not rigorous. So the whole thing is just nonsense, and it bounces back and forth. And what I love about this is that the guy is like offering the cow, there's two straws, the two straws slays me, but then he's like, there you go, cow. OK, but the point, there is a point, the point is that science communication is important. And chocolate milk is delicious. Let's talk about some real science. OK, so that's popular culture stuff. This is the stuff that pops up in your news feed, in your email, this is what I work on. I've written a paper on this star. I've worked with the lead author of this study before. This is a really amazing, true, amazing detection of what's called Boyajian star, named after Tabitha Boyajian, a professor who discovered this amazing object. And here's the deal. This is why we all went, whoa, it did this. It had these wiggly lines. And to scientists, that's a huge deal of wiggly lines. And because the shape of these lines were totally unexpected, something passed in front of this star to make it go dim for a day or two, and it had a really weird profile, and we don't really know what it is. And that's the God's honest truth. We don't really know what it's probably does, or a comet, or a bunch of comets or something. That's not that exciting. Nobody's going, wow, out there. OK, so the Atlantic picked this up, because that's kind of cool. It's a really unusual discovery. The most mysterious star in our galaxy. All right, that's fine. That's fine. I don't have any problem with that. Astronomers have spotted a strange object. Yeah, that's fine. Scientists study extraterrestrial civilizations are scrambling to get a look. I get a little worried. We're OK. That's fine. It's fine. It's the Atlantic. It's a good publication. You should subscribe or whatever. Here's a funny outfit called The Washington Post. The flickers are consistent with an alien megastructure like this artist concept of halo or something. Is it flickery because of aliens? Show more? It says no. It should say no. OK, this gets better. This is the fine folks at Discovery. Again, we're not trying to dunk here. We're just trying to point out interesting facts. Here it is. Has Kepler, the space telescope to discover this, has Kepler discovered an alien megastructure? I love this one, because the artist rendition is so, so pointless like it looks like. Why did they cancel it? OK, here's one more on Voyage and the star. Have aliens built huge structures around Voyage and the star? Probably not. But alternative explanations are hard to come by. This is true. Here's another good artist rendition. It looks like a bunch of iPhone 8s centered around a campfire, which is funny. And here's the really funny part about this one. Scientific American is a pretty reputable publication. Here's the funny thing about this one. This guy, Jason Wright, is a professor of astronomy at Penn State University. He is an absolutely brilliant scientist who I've worked with. And he, and this is a former graduate student of theirs, Kimberly Cartier, they are the real deal. And this is the problem. You've got to write this, or at least the editors think, you've got to write this headline to get people to click to read the article. The article is completely sensible. But the headline is ridiculous. And I'm making fun of Jason because he's smart and I love him. But we do look for weird stuff. We do look for weird, exotic patterns. This is an illustration that I drew of exotic patterns you might see in data that could be indicative of aliens. Jason himself actually works on the honest to God search for extraterrestrial intelligence. It's a fascinating topic that's finally getting some traction and not being just laughed at. I'm hoping to come back and, yeah, thank you, right? That's awesome. We ought to look. I want to believe, and we ought to look. So there is real science here. But, oh, golly, we need to be careful about reporting them. These searches and these finds, we got to be really careful. We have an obligation as scientists to be really careful. And I worry. I worry that we're not. But ominous logo hiding off the side of the screen. But we are faced with an even bigger challenge, a challenger who has a lot bigger machinery behind them that we are going to have a hard time beating. And that is the social media science fan accounts.  Occasionally get it wrong. But they actually do really care about science. I don't want to pick on them. But I want to pick on some other people here. OK. Here is an account called atPhysics-astronomy, or atOrgPhysics. They got a really cool domain name. Here's a picture they posted September 6. View of Hurricane Dorian from the coast of Florida. Spoiler, no it ain't.  We don't get a lot of them in here. But they're a big deal.  They're not really that funny. And if you saw this on the TV and you went outside and freaked out, like, oh, we got to pack up and run because I recognize this coastline. We got to run. This is not great. I don't like this. This is unethical. I think I would categorize this as. And they have 110,000 Twitter followers. This post had 100,000 retweets.  Here's another one from atInterestingSci1. I mean, to their credit, they don't try to explain what it is. They just say, wow. This is like a baking experiment gone wrong in, what is this, Toronto or something? Shout out, shout out Toronto. This is Tim Hortons. They have 140, 143,000 followers. This has 15,000 views. It is, I don't know what. I mean, like, it's fine if it's art. It's fine if it's art. It's cool. Like, it's engaging to your eyeballs. But like, it ain't science. And it's not science and nature, the account title. You know, I worry about this. This is what's causing me worry. How do we fight back against this? Here's one more. OK, atZonePhysics, which is sweet Einstein logo and a cool banner. And oh, they got a great URL, physics-astronomy.org. That's cool. That's a great URL. I wish I had that domain. And 800, almost 850, better part of a million followers. And they posted, this is yesterday, November 20, 2019. Yesterday morning when I grabbed this, it had 250 retweets. It's since grown. Pluto has been reclassified as a planet. Rejoice. No, it hasn't. That is a lie. Not only that, if you click on their silly website and you go to the article that's linked, it's a link to an April Fool's article. What do we do about this? OK, yeah, physics, whatever. Here we go. They're a big deal. They got lots of followers. This is a huge impact for nonsense. This is going to cause people a lot of confusion about what we do. That upsets me a little bit. Not like, damn it, you've got to get it right. Or like, you should know better. But like, the due diligence. Where is the celebration of truth? You got it wrong. I'm not worried about that.  Where is that post? Where is the integrity to say, we messed it up. It's OK if we get it wrong. I get it wrong all the time. At 850,000 followers, there are only two astronomers in the world with more Twitter followers than that. One is Dr. Neil deGrasse Tyson in New York, TV celebrity. The other is Dr. Brian May, also known as the guy from Queen. He was only in one of the biggest fans of all time. And he's only got a million followers. So go follow Brian May, huh? And then this account slides in above Phil Plate, the bad astronomer, who is one of the biggest deals in astronomy communication. If you're not following Phil Plate, man, get on your phone right now. Ignore me. I got 2,000 followers. Ignore me. Go follow Phil Plate. He's the real deal. These people are crushing him. Like, this is concerning. Why? Why does this page exist? Here's your answer. This page has nothing to do with physics and astronomy, of course. It has to do with affordable islands. And a man turning an airplane into a house, which actually does sound really cool. And look what the deepest hole in the planet has. And this yacht, right? These are ads. I think this is self-explanatory. You can understand what I'm saying here. This is a machine to get you to click on things, to get your eyeballs on things, to get you to engage with things, so they make a few pennies. And they do that a million times a day. That's depressing with my beard. Dramatic interlude. So what can we do about it? And I don't mean just, like, what can we, the noble astronomers, I mean, like, we, you, what can we do about this? Because the fact that you're here gives me a lot of hope. The fact that this is the 56th event for Astronomy on Tap Seattle. Shout out to Astronomy on Tap Seattle, a 56th event. Amazing. It's freezing.  It's not actually freezing. That's true. I'm honest. What can we do about this?   The internet is why we're all here. The internet is how you found out about this event, likely. The internet is how I reach people every day and communicate science. The internet is a great thing. This is, like, a cultural problem, the weak-hand address. I want to end this on a hopeful note. So I have three action items, three things that we in this room need to do. Number one, we need to communicate about science. We as scientists need to communicate science. There's a great little blog post by Professor Michelle Franco from Bryn Mawr College. And she ends it by saying, if we don't tell them what we do, the pseudoscientists will. They will fill that vacuum with nonsense. Now, she's a chemist, and so people are worried about putting chemicals on their hair and vaccines and stuff like real problems. Vaccines, vaccines are good. Vaccines are, they're a good thing, and chemists worry a lot about bad reputations. Yeah, if we don't tell them what we do, the pseudoscientists will. That's a real threat. So, to the scientists and the science folks in this room, tell them what you do so that nobody thinks these things. So, that nobody thinks that chocolate cows make the super blood moon or whatever. We've got to tell them about the science. We've got to spread truth. It's important. Number two, you, more broadly, the people in this tent, can help share and intervene. One of the only ways that we can beat fake news, oh, I think that's right. One of the ways we can beat, we can so-called beat this kind of phenomenon is by intervening and telling people, actually, that was garbage. And it feels so helpless in the moment when you have these tiny interactions, when you're butting heads with your great aunt or whatever on Facebook. But like, look, 250 retweets. We've got to try. We've got to try to intervene and tell people that wasn't true. There is research. There is research. I should have put a citation here. There is research that shows that by making these interventions, by telling people that like, hey, that was not a really reputable source that you linked to that one time. Maybe you should try. People actually do tend to get a little better. There is some hope that by elevating the discourse of people about science and about truth more broadly, that we might hope to center around something in this world that is true again. I think that's an important thing to strive for. And you all can help. It matters when you subscribe to somebody like Phil Plait and retweet the things that are cool about science. And it matters when somebody retweets the super blood moon over Rio de Janeiro with a cow jumping over it. You say, that looks like Photoshop to me. I don't think that's real. Those things help. Third, and I think this is a more subtle point, but because we're in Seattle, I think it's worth standing up here and trying to make at least. We need the help of technology and technology companies with this problem. Now, I'm not the only one saying this by any stretch of the imagination. Finding spam and finding falsehoods and fake news is a huge deal right now, and a lot of really smart people are working on it. I took the screenshot of the Google Optimize Resource Hub, which is just like a documentation hub for how to get people to look at your website and click your links. This is a really useful resource for developers who are trying to make websites that are pleasant to look at and great because they want eyeballs. Because the entire economy of the internet is based around eyeballs. We need other solutions besides just eyeball time equals dollars equals the only thing that matters on the internet. We need tools that help us optimize for things besides just eyeball time. We need tools that help us figure out what's the most efficient way to get knowledge across. What's the most efficient way to identify bad actors who are spreading misinformation and intervening when people are trying to share that content saying, just so you know that that's BS. How do we get these tools? I am not a programmer by trade. Some people in this room probably are. This is something important that matters to us. That matters to scientists. We need tools and we want tools to help build partnerships that will reward people who are creating science and science knowledge. Also, Dr. Jesse Christensen, another amazing astronomer. Vlogbrothers, I think the best channel on YouTube. Shout out Vlogbrothers. Hank and John, there you go. We already do this to an extent, right? These platforms verify or put fancy check marks or stars next to people's names. Why not little brains? I don't know, this is like a cute idea. These are good sources of reputable truth and knowledge. Why not reward this by helping draw the reader to these kinds of sources? This is one trivial example. Going back to number two. Technology companies and advertising companies will care if we all care. If we are subscribing to scientists and broadcasting that message of truth, then they will pay attention.  So subscribe to your local homegrown scientists and to your truth. Alright, and in conclusion, again, these three action items. We need to do science outreach. We need help from everyone to spread truth and to identify falsehoods. And we need the help of technology companies. And with that, I will thank you all for coming out again tonight. Time for questions, but I am going to drink the rest of my beer. Good question. The question was what clickbait have I fallen victim to that turned out not to be true? That's a really good question. Well, first off, there's a lot of borderline clickbait-y headlines that we put in our own research articles. People put falsehoods or very misleading titles occasionally. That, I often fall victim to and read the article, but that's probably not a bad thing.  It's cloudy here and we don't get very good eclipses. I've never seen a full eclipse, but I fall victim to those. And other cool aurora photos, I have been retweeting some fake ones as well. They just look so cool. The art is so good. Oh, a really good question. A really actually good question. How do we know that Tabby Star or Boyajin Star is not an alien megastructure? The short answer is all the available information right now points to it being dust. Some kind of thick, grainy, opaque dust. It changes in color slightly when it gets dimmer, and that is consistent with dust. The other reason we don't strongly suspect aliens is that incredible claims require incredible evidence. And right now, the simplest assumption that we can explain the data with would be dust. Aliens would be very, very complicated. It's not obviously physically impossible. So when you start talking about trying to detect aliens, you want to try to detect things that are otherwise utterly impossible. And dust is very possible. There's plenty of dust in the universe. Yeah, how would they even build this megastructure? Super good idea.  A Dyson sphere would be the idea. Jason Wright actually is one of the people who have shown that we don't see any evidence, strong evidence for a Dyson sphere.  And that means your structure would heat up and your structure would then radiate warmth, infrared heat, like these lovely lamps above us. They would radiate warmth. And we have telescopes that look for infrared light. The wise telescope famously surveyed the whole sky about a few hundred times over the past decade in the infrared. And so Jason Wright and his team have shown that there are no stars that show anomalously high infrared glows. So you don't see any, like, weird stars that are oddly faint but have huge infrared brightness, which would be explained by reheating from a Dyson sphere. That's the best evidence for that. Yeah, back there. Shout it out. Great question. Thank you. I didn't even plant this one. Other than this, what am I doing to make my research more accessible? Well, you can go check out my YouTube channel, LOL. A bunch of people at the UW, including myself, try to put ourselves both on social media like YouTube and Twitter. And we try to shout out each other's work, try to tweet about it, try to post about it. I try to make videos. There are other people who try to make videos and work into an everyday understandable language. One thing that has been shown time and again to really work is just cutting out jargon. It's just getting used to talking about what you're doing in an everyday kind of context. And so trying to put myself into a context where I'm doing that every day is important. So shameless plug for my own social media accounts but also for the people who are here and run AOT. One example of how I try to get my research out is I come to and I support events like this. Yes. Ooh, good. Put me on the spot. The question was, she appreciates that I said it's okay to be wrong, so put my money where my mouth is. What's one time that I was wrong in my research? Well, let's see. There's been plenty of times when I've speculated out of hand. So one time that I made an inaccurate prediction. I published a paper seven or eight years ago about two stars, a binary set of stars that were orbiting each other, they're cotton each other's gravity. And it's a very short period. They rotate around each other, they orbit around each other every, I forget, every eight hours or something. It's incredibly fast. These two stars are locked in this cosmic death spiral.  And I really pushed that data. Like I really strained to try to see if that shift, if those stars were accelerating, if they were spinning in faster and faster and faster, which would indicate they're about to collide. And this causes what we call luminous red nova or like some kind of stellar merger. They're really cool and very rare. And I was like, ooh, God, maybe I found one. And so I really, I wanted it. I was a young graduate student and I wanted to find this thing. You can go and find this paper. And there's a very suggestive plot that does not have very good error bars. Where I show, like, if you take this side of the data, we look for what the rotation, the orbital period is. And then we take this side of the data, look, it looks like a line. And that suggests that it's inspiring and this is going to be really amazing. And then we came back like a year later with a better telescope. We sat on the star for like six nights. And it's not doing that. And I didn't publish that. Right? Like there's me owning my shame, my wrongness. I was a young student who needs a job and is trying to win grant money and it's not exciting to publish like I was wrong. Like that's not an exciting paper. I got another paper that I'm working on that's cooler. Don't ignore that. Don't worry about that paper. I got another one coming up. Right? And like there's these games you play because you need attention. Because the eyeball economy isn't just the internet. It's about grant funding. But there you go. There's the honest answer. This has been healthy. How do we change the incentive structure in academia? Yeah, I have one thought. I'm not sure if it's super helpful. I think so a lot of what people like me, so I'm a research scientist, I don't have a ten year track job, which means I'm not paid by the state. I'm paid by grant money that the feds competitively allocate.  It takes like, you got like a one in ten chance of winning one of these grants. And it might support you for a couple of years. So you gotta spend a ton, you can do the quick math and figure well it takes me a couple weeks to write a grant. I got a one in ten chance of getting it and it's gonna support me for two years.  Just to play the game.  Like it sounds tongue in cheek because I'm lazy and I don't want to write grants, but it's also not clear that past a certain point that we can differentiate what's going to be the best science, the most transformative, the most spectacular or the most important. These grants and these dollars are precious and limited. We spend so little money on NASA and on the National Science Foundation and the National Institute for Health that you convene a committee of like-minded people and people with PhDs and very serious scientists to pour over 20 or 30 of these grants to pick one or two and how do you pick they're all good or at least half of them are great. How do you pick? I don't know. It's not clear that we always pick the best thing and so some people get lucky because of their reputation and some people are doing the cool, hot new thing and some people are out in the Never Never Land trying something cool but nobody's heard of them and they don't get lucky. I don't know. I think one possibility is making some fraction of the money equitably available to all. That to me seems like one possibility. It's a radical change. We take the idea of peer review and judgment very seriously in academia and we're going to be really reticent to get rid of that. But it's possible. Anything's possible. Thank you all. Tip your scientists. I'd like to introduce our second speaker of the night who will be telling us an abridged history of the universe. Please welcome... Sorry, technical difficulty. We're making sure our live stream is on. Are we ready to go? A moment to build the tension so you can be really excited about our next speaker. I guess in the meantime I can announce that we will not be having an astronomy on tap in December due to the pervasive darkness and cold and also traveling to see our families. But we will be back the fourth Wednesday of January 2020, starting a new decade. Astronomy on tap number 57. So we hope that we'll see you there. Dear patients, we are a ragtag team of UW graduate students who put on this event. And sometimes things don't work out quite as quickly as we hope that they will. So, machata to our videographer for keeping our live stream going every month. I'd love to introduce our next speaker of the night at University of Washington, astronomy professor, Professor Matt McQuinn. Thank you. Since my colleague Jim basically didn't cover any astronomy, I decided I had to pack a huge amount into this top. And so in the next 15 minutes I'm going to summarize everything we know about the universe. Okay, and I title this a universe is life and you'll see why. But so before we get started so before I start before we discuss the life of our universe there are a few lessons that we have to discuss. And so the first is that that space likes to move. And so what do I mean by space likes to move? This means that space doesn't like to be static. It either likes to expand or contract. And there's nothing so mysterious about this. So when we look out at other galaxies almost all other galaxies are moving away from us and the further we look the faster they're moving and this is the expansion of space and it's totally correct to think of those galaxies as moving away from us. That's what expansion of space is. It only gets tricky when they're moving at what looks like faster than the speed of light. You need to think about it in a different way. Expansion of space is just things are either moving away from us or they're coming towards us. So nothing mysterious there. And also I should say that there's also no center for the universe. So if I were in another galaxy and I were looking at other galaxies I would also see all of those galaxies moving away from us. That's lesson one. Lesson two. So space is expanding if we go back in time things were denser. Everything was closer together. All galaxies were closer together. If I took the air in this room and I compressed it it will heat up. In the same way that if I blow air out of my mouth it will expand and it will cool down.  So the process in reverse if I took the air and I compressed it it will heat up and it will heat up more and more as I compress it more and more. And eventually what happens in our universe is things get so hot that they start hitting each other and producing other particles. They might produce electrons. Or if I get them fast enough they might start producing particles that we've never seen in the lab. And so the early universe is way different from what we're used to because the things can get really hot and this means that we can get an exotic zoo of particles that we've never seen. And lesson three after Jim's talk I acknowledge that my title is a little bit clickbaitable. Please do not quote me but so light travel equals time travel, ultra deep field. And so this is the deepest image we have of the sky almost every everything that you see in this, every source is a galaxy. The size of this is about a hundredth the size of the moon. The size of the moon, if I put my thumb at an arm's length the size of the moon is roughly the English size of my thumb. This is a hundredth the size of that.  Like there are a lot of galaxies in the universe and there are stars in our galaxy. There are a hundred billion stars in our galaxy in the observable universe. They're more like a trillion galaxies. And so the closest galaxies which are the biggest galaxies are a hundredth of millions of light years away. That means it's taking hundreds of millions of years to travel. So we're looking back in time. In this image the furthest galaxies we know of have been found in this image and they're like little red dots. I don't know where they are but they're like some little red dots. These are basically galaxies that are where the light has taken 13 billion years to travel to us. And the reason they're red is because the universe has expanded roughly by a factor of 10 since their light was emitted and this has stretched their light. If you stretch the wavelength of light it becomes redder and redder. Okay. So those are our three lessons. So now 7,000 years if I were in the room I would be like running. As you guys know who answered the quiz correctly that 14 billion years ago or exactly 13.8 billion years ago. And the next line is going to sound amazing from my voice. In a world before there were worlds an unfertilized universe. This is it. It's too small to be cute. This is the universe before our universe was the universe. What I'm going to show this is a time when we really don't know what things look like. Things probably look a lot more crazy than this. My imagination is there are broken beer bottles. But what you're going to see is that the nice thing about our theory for the creation of the universe is that it doesn't depend on how many broken beer bottles there are. The universe looks the same in the end. And so I'm going to and so what we most of us cosmologists are convinced happens is that there's some particle particle that we probably haven't created in the lab. And so this is a simulation of what it does. And so this particle is just existing in the universe. And it turns out that this particle, it has certain properties, the troughs in the simulation have the right properties to seed our universe. And what I mean by that is that those troughs in that simulation, the things are actually growing exponentially. And so for a human we're all familiar. So a human, you know, like three weeks looks like an egg or whatever, and then it keeps growing. So the universe the universe you would not want in your you would not want in your tummy. So this is the beginning of time. After 10 to the minus 30 seconds it's doubled in size. Then it's doubled in size again by two times 10 to the minus 30. Then it's doubled in size again. And this happens a hundred times. In fact, in our theory for things to work, you need to take a one meter region and you need to stretch it to the size of the observable universe. And if you do that it explains a lot of observations that we see. It's kind of amazing. And this is called inflation. And so if I, like quickly you can see that if I keep doubling this even by like 10 this is going to be so much bigger than anything.  Okay. And so a miracle occurs. A real miracle. Which is that if you let the universe grow in this way, then on really small scales our universe we don't really notice this but there are actually particles really short time scales appearing in and out of the vacuum of space. They're just appearing and disappearing. And this is quantum mechanics. And it's actually important for many things. It's important for like a lot of processes that this is actually happening. And so the these particles, these quantum fluctuations sometimes there are more particles in one place in the universe and then in another place but it's only on really, really small scales but if you then cause the universe to expand so fast that these small fluctuations are actually stretched to every scale and they should have certain properties and we look up at the sky as I'll show you in a second and the sky and we see that the universe, like the seeds of structure are actually these quantum fluctuations. So we are descended from these quantum fluctuations from inflation. So this is the miracle of the exponential growth. Okay. And so this is kind of my most complicated slide but okay, so then we have this particle that caused the universe to expand exponentially and then this particle it goes into other particles because our universe is way more complicated than a single particle. So it goes into other particles. This is called reheating. We don't know exactly when this happens. It happens early. It looks like this. And some of the things it goes to like one thing it goes to is dark matter. Because there's a lot more matter in the universe than the matter that we're familiar with. One of those particles is created in the early universe and it's called dark matter. We just don't know what it is. Another thing it goes into is quarks eventually and then those quarks eventually become protons and neutrons. So this is and also it goes into electrons and something that we know happens in the early universe is that before once around one second in the universe there were a lot more electrons than there are today. There were also a lot more quarks before a millionth of a second. There are actually a billion times more electrons, a billion times more quarks but there are also anti-quarks and this had to be the case. We have an observable that tells us that there were these positrons anti-electrons and they annihilate and leave only one billion of the electrons at the end the ones that are actually in our universe. Okay, and so yada yada the protons and protons as you guys had on your quiz they eventually form hot air balloons or balloons and then eventually the electrons, things are really hot but when things get less hot the electrons like to bind to things they like to bind to the protons and the helium and when this happens, the light is released. There was a lot of light there was a lot of radiation that was kind of trapped by all the electrons the electrons then grab onto nuclei and the light is able to travel and this leads to emission that we see. If we could see one centimeter wavelengths then what we would see and we see this with our telescopes is that certain regions, when I look at the sky in certain directions certain regions have a little bit more have a little bit more radiation from the Big Bang than other regions but they all have kind of the same amount of radiation and this is what the sky would look like at a centimeter. If this were Seattle like if I looked up above Seattle like I could see at a centimeter in some regions have more stuff than others and this is the light that's been traveling to us for 14 billion years from this time when the the wind was released by the electrons and so in particular the so what I'm showing here is if I were looking at just a small patch of the sky this is the whole sky and so the just like the Earth is a sphere the sky I can think of as a sphere and like just like I can make a map where this is like North America South America Europe and Asia I can do the same for the sky and so this is the sonogram of our beautiful almost baby universe and I'm a cosmologist which is a special type type of doctor and I can tell that in 14 billion years this universe which is doing fine is going to have an astronomy on top things are kind of boring these are like these are actually part in 10,000 fluctuations these are just small fluctuations in the universe that we're seeing look at different directions just see a little bit more radiation which means there's a little bit more stuff in one region than another and so what the next thing that happens is that there's gravity and gravity makes things when there's more stuff in one location gravity makes it amplify like I like to fall to the earth like stuff gets denser and denser and so eventually things get dense enough that interesting things happen and so the first interesting things that happen are kind of around a couple hundred million years it takes the universe a bit of time and you start getting stars and so this is a couple hundred million year old universe so you start getting stars from the universe and then it turns out that our universe went through a pretty angry or turbulent adolescence and so you form some stars and then those stars go into galaxies and then and when you get a lot of stars stars like to explode and then they start blowing gas out of galaxies and so in the past there was a lot more star formation than there is today and so this is an actual simulation that people have run of of what the of the couple billion year old universe looks like and so in fact you can see this is a few billion year old and you can see that the so this is galaxies forming and then when the galaxies form stars the stars like to blow up the big stars and so the presence of our universe was a bit turbulent and so this leads to the presence whoops and so the presence you look up at galaxies and they're not doing a whole lot our galaxy is kind of boring it's not forming that many stars there are these elliptical galaxies like in your question that basically aren't forming any stars and so our universe now it's boring now but wait recently this is what we expected this is a healthy universe just look good this our universe is not healthy our universe is growing very very quickly galaxies are getting very very far away from each other actually most galaxies in the future we're not even going to be able to see them they're going to just move away from us too fast they'll just disappear and so this is not good and so that brings me to the end the end of the universe the end of the story the end of the universe is cold we think and it's dilute and it's dark thank you questions this is a question that we have trouble answering so the all that we can see is that so we can see today that the universe is like we can see things that are 14 billion light years away in essence the universe is expanding so it's a little more complicated than that and we can see that things look the same there as here that maybe we're looking back in time a little bit because the light's been traveling but and so we know that the universe is a lot bigger than what we can see and in fact from studying things like the sonogram which is the cosmic microwave background we can tell that the universe probably has to be uniform on a much larger scale than what we're able to see and in fact this process of inflation it would be surprising although there are theories that do this it would be surprising if the universe were just kind of as far as we could see so probably things are way bigger but we can only see as far as light will travel ok so the question is in my opinion what is the best theory for explaining dark energy and so there's a standard answer to this which is that it's the energy of the vacuum of space time it's the same vacuum I was talking about where things are appearing in and out in this theory with quantum mechanics we can calculate the energy of the vacuum of space time and we make a prediction that it's way big it's 10 to the 120th power off and so then how we explain this especially this is how the string theorists like to explain it is that you can actually have the amount of energy in the vacuum fluctuate from place to place and so imagine the universe is just way way bigger than anything we know and that there are certain regions where this vacuum has a much higher density and there are certain regions like ours that are very unprobable but have a low vacuum density and then you can say ok why are we existing in this region where the vacuum energy density is so improbably low and so you can calculate and you can find that actually structures will not form in the universe where the vacuum energy is much higher than our part of the universe and so this means that so that maybe we are only living in this huge multiverse but we can only live in one part of it because the vacuum energy is low enough that we can live here and that's called anthropic reasoning some physicists totally hate that actually the last time I gave a talk here it was on the multiverse but the but the other theory is that it's like this similar to inflation that you just have some particle and this is called quintessence people criticize that theory and that the tuning might even be more extreme than you need for the cosmological constant to have a particle at today it's very natural to have a particle in the early universe when the energies are high cause the universe to expand a lot it's much harder to have it happen today although this is also something that's gotten really interesting because the string theorists have come up with arguments that maybe there's a particle but I won't get into this this is getting too technical so this is something that people are thinking a lot of actually many people think of this as the biggest difficulty with current modern physics the thing we understand the least so you're not a string theorist? I'm not a string theorist I'm a cosmologist what questions do you like to answer most in your lifetime? what question would I like to see answered the most in my lifetime that's a really hard question there are questions that seem easier to answer so I think answering what the dark matter is is something that is more likely for us to answer than what the cosmological constant is but the other one might be more deep I think something that we kind of we might understand this inflation a little bit better we don't know what particle is doing it and so we might be able to say things about this multiverse what the structure of things look like before inflation I think that would be really cool people recently said something about a fifth elemental force does that just click bait? the second part of that how does that tie into dark matter and expansion and all of the things we're trying to answer the question is he saw something about a fifth force is it click bait or is it not? I think it depends on exactly what the content was so what are forces? so forces are different particles being exchanged between other things electromagnetic force electromagnetic force is photons that are causing an electron and a proton to attract and so there are other particles in the universe probably but it's hard for there to be particles that are light enough that we haven't produced them in the lab for them to create a long range force so the answer is probably there's nothing important the forces that we don't know are really weak forces that aren't relevant for anything for anything for you guys for physicists it's really cool if you find some other force carrier it is telling you about the fundamental theory of everything it's a clue into the structure of the universe but it is very unlikely there's a force a new force to find that's important if there is a new force it would probably have to happen for the dark matter because we are made of dark matter so it's very hard or the dark energy you could have forces that don't interact with us and then it would be easier for them to exist yeah so that's a good question and that's actually the why I said things are it's a cold dilute dark end is that the so things so the lifetime for the sun it's going to be around for 5-ish billion more years and Jim could probably correct me on the significant digits but the longer but they will all eventually run out of fuel and some stars are forming but the formation of stars is slowing down partly because of dark energy and so less stuff is falling onto galaxies you need gas to fall onto galaxies and funnel to the center to make stars and so in 100 billion years there will be very few stars in the universe so the universe will start turning off and so in the distant this is probably not the first thing we should be worrying about but in the distant future the universe as we understand things and this understanding does hinge a lot on our understanding of of dark energy but in our current picture the future of the universe is pretty dark and I guess that's also the current situation of the universe or of the planet it might not be too much better yeah so it actually fits really nicely with this inflation so you get these quantum mechanical fluctuations that turn out to have very specific properties and so the spectrum of these exactly where galaxies form we have amazing models that are very accurate for predicting kind of that and so this web so you start off with these fluctuations that were from this very early time and they grow via gravity and the reason it looks like a web is this is a little bit harder to explain to a lay audience but there are okay I'm not even going to try to explain but it's basically it's because there are if you know what a tide is like the moon pulls on one side of the earth more than the other side and this causes tides on the earth the same thing happens where you have huge tidal fields in the universe and it turns out that if you work out the mathematics it is not that complicated that you get this philometry structure which is called the cosmic web any other questions well for me as a cosmologist yeah so the stars going out would be one end but so it depends how imaginative you are so that's not the last thing that happens in the universe so the there are still things in the universe they are like black holes and so the often people do quote the end as the black holes do evaporate too and so that takes a lot longer especially for black holes of the masses in our universe and so the end actually the expectation is if you wait long enough you just have a bunch of particles floating around in the universe and then there is a paradox for me this is like a ridiculous paradox but then I have a bunch of particles floating around for the rest of time and so there is some chance that they will like coalesce together and become a human and so the you have a lot of time in the future this is called the Boltzmann brain paradox or they become a human brain and so you have consciousness and so there are the claim is that that might be the most prevalent life like if you're and so then maybe those are the universes where I should be saying that life exists like that's the condition on life and so and and then but then it's I don't know maybe that's too much but yes maybe this means that we are paid we are funded too much I should never say that but because definitely these are things that people think about the inflation flat now with that curve yeah how much inflation is in you so this is a good question the question is does inflation end or does it we know that inflation has to end because we exist and so the inflation particle has to go into other particles and see the universe and so then but that's not the only thing like so there's a reason this is not the only reason our existence that we know that inflation ends so we can look at the cosmic microwave background and we can make predictions if inflation ends it has to start decelerating at the end like it can't always be exponential and so we can predict what that should look like in things like the sonogram the cosmic microwave background and we see it we see the inflation ending in the way it would if this theory is right and so this is also something that makes us think very much that we have a good idea for this creation in my opinion this is the most ridiculous theory that we have that we have a theory for what happens in the universe when it was like 10 to the minus 30 seconds old and we actually don't know too much for a while after that but it turns out that how this theory works it's very robust and so we have a theory that has a lot of things that we can observe and they've all checked out that like so the this I find super profound done? or there's one more question? okay last question so if everything is kind of fading out it's like kind of a pool what does that energy go because if I do it with laws we should assume that it's just converted but where does that go if everything is kind of it sounds like it's unenergized yeah so this is a good question like where does the energy go and I think a related question is just like is energy conserved? I'm telling you space is expanding and the answer is yes there's energies conserved and at the end the energy is so the even though things are getting cold and dark what is happening is there is light in the universe it's come out of a bunch of stars and whatnot and that light is around it's just getting stretched it gets stretched as the universe expands and that's totally consistent with conservation of energy because it's stretching actually slows down the expansion of the universe and so that's where the conservation is happening and so it's getting the light and by when it gets stretched that means there's less energy in the light and it's looking colder and colder so in order for me to see the light from stars I would no longer be able to see it with my eyes because my eyes can only see certain wavelengths of light and so it will get stretched to wavelengths that are just two the energies are too low to excite like electrons in my eyes and I can see and so the things it just fades away in a consistent way but energy is totally concerned okay thank you both of our speakers one more time


Yo-yo everyone. So brief update video. I wanted to throw out some news just so people would know I'll go ahead and do it all at the beginning of the video and then explain it all later But just some talking points Well, first off I am now a PhD candidate. I The reason I haven't been posting videos in the past month or so is I had a bunch of stuff to do I had an oral offense. I just had a bunch of different assignments and presentations and just different stuff That's why I haven't been posting recently But I'll still be active on the forum or Twitter or whatever or however active I usually am But I'm gonna be making now now most of it is sort of beyond me or past me or whatever So I'm going to be putting up more videos now just so you know, I'm still here. So news entries I'll go ahead and mention them all right now. First off got my x220 back. It is working actually better than new It's better than it was before I'll talk about that in a second Second off, I'm gonna be presenting at Linux Fest southeast for those of you who are in the southeast of the United States or somewhere else around there Also, let's see. Oh a couple videos. I want to talk about in a second and Yeah, there's probably something else. I think I had another thing, but whatever. So anyway on the x220 Month or so ago. I mentioned that you know, I was repairing this thing and I forgot to unplug it at some Period and it fried it fried the screen connector between the motherboard and the screen And you know, I put up a video like apps. I'm just gonna use my x200. I'll think about this later Now I get a bunch of emails from people one of them was from Tripcode Who's another youtuber who I mentioned in one of my last videos and he volunteered basically to just repair it So I'll give you a link to the video where he actually repaired it But I send it off sent it off to him and I he replaced the motherboard I think he replaced the screen as well I think he had a lot of these pieces laying around but he might have I think he actually bought he might have bought a new Motherboard so anyway, thanks to him a lot And so he repaired it and not just that When he fixed everything, I think he got some kind of motherboard error or something like that Nothing fatal just something you have to click through But he asked me hey you want me to just flash core boot on it and I was like well, okay Sure, so this thing now actually has core boot on it So that that's really nice. So it's better than it was before so to speak There they're actually still some things. I think we're figuring it out. But yeah, mostly it's it's all it's fantastic Works great on it's nice to have the computer back again. Actually, it's really it's like a theses is ship kind of thing Is like it has a new screen has a new motherboard. Is it really the same computer? Hmm? It still has this one screw on the bottom that doesn't screw in right so I guess that makes makes it the same computer So anyway, that is that So with respect to Linux Fest as I said, I'm gonna be presenting. Where is it?  Of course, you're welcome to come I forget if there's a Participation fee. I don't think there is But there might be I don't know what I don't want to say they do have a bunch of sponsors So I don't think so see I'm used to all these academic conferences where a lot of Lower tier ones will like ask you to pay money or something like that. But anyway, so I'm gonna be talking there I'm I forget my exact talk topic, but it was something on software minimalism and how people should basically embrace it And I think that this the time slots they give again another thing from academic conferences I'm used to presenting in like 20 minute time slots I think they're giving me an hour or something like that They give everyone an hour or at least they did in previous years. So that's gonna happen So yeah in my personal life I'm moving back to the Southeast and that's one of the reasons I'm presenting at the Southeast one just so you know And let's see if there's anything else and there's probably something else that I meant to say But that's basically it a long story short is in the next couple days I'm gonna be putting out a lot of video I don't want to say a lot, but I want to put out one every other day or one every day depending on how much work I can get done So one of the ones that I'm gonna be putting up pretty soon is a promised video from I think I promised it like a month ago And I haven't done it And that is in fact I promised it on patreon, which you know should I should definitely do it And it's just a bunch of personal reasons I couldn't but that's gonna be a video configuring a Fresh install of Arch Linux, so I'm gonna do that. I haven't like 90% prepared I just never had the chance since I lost the think pad Temporarily I didn't have the chance to actually record it and do some other stuff that I needed it for But now I'll be able to do that and there are a couple other videos actually sort of interesting ones that I'm gonna have coming out soon I don't know if I I don't know if I want to say they're a little different, but we'll figure it out So anyway, that's about it. I gotta go. I'm actually I have to get somewhere. I gotta gotta go cook this ham So I'll see you guys pretty soon I'll probably put up a video in the next couple days whenever you're seeing this so have a good one and I'll see you next time


Alrighty, I have really big news to drop on front gate renovations. I also have even bigger news to drop tomorrow. So this isn't even the big news. But as you can tell, not much going on with that waterslide moose horn falls over there.  So at front gate, it looks like they are rebuilding those old paths. So for those that don't know underneath Leviathan, there used to be paths that would travel under it towards front gate. Front gate has definitely struggled with having like large crowds, not being able to house everyone in there. And what I think this potentially could be is that soft renovation, where they build two larger lines that come into front gate where they'd kind of have pre screening those metal detectors that are really easy to use. And then you walk into the front gate area and you'll be able to purchase tickets on a self service kiosk, instead of having to line up at those manned kiosks. Here is the Kingswood tent with the behemoth trains and the old vortex trains from Kings Island. I do want to say though, I want to point out something that this is Rutherford construction on site. So for me that definitely is a sign that this is a lot larger than just laying down some brickwork. So we'll definitely be keeping our eyes out. I also wanted to point out that if this was simply just to build a path, this is also way too early just for a path. Wonderland would have started this in spring and finished it off right before opening. So if it's just brickwork for a path, it's way too early. The company they hired is way too large of a company for just simple brickwork. So I am expecting a much larger project with this. Again, I am expecting, I'm not fully sold. I want a fingers crossed. Trust me guys, I want a fingers crossed and this is our front gate Renault. But I am more so thinking this is going to be a soft Renault where we're given self-serve kiosks and a more automated front gate experience to lessen the labor cost that Wonderland suffers in such a high wage market. And I'm not saying high wages and I think the wages are too high. I'm saying to accompany in a business, the wages are high in their perspective. But with that being said, you have a big large excavator digging up that side over there. Then you have a smaller excavator digging up the paths. And yeah, so definitely really exciting things. They're starting really early, which is really promising. And it looked like marketing was down there filming on a gimbal. So again, even more promising signs that this could be bigger than maybe even I'm expecting. But nonetheless, stay tuned for tomorrow's really big news.  But if not, yeah, stay tuned. Something could be leaving. All right, have a good one guys. Bye.


Greetings and welcome to the Introduction to Astronomy. In this lecture we are going to talk about planetary formation, and we looked at this previously, but we are going to look at what the discovery of all these exoplanets has done to change our perspectives on how planetary systems form. So what are other planetary systems like? Well, our early thoughts was that the planetary systems would be like ours. Why? Because that's the only planetary system we had to go by, and we would expect things like circular orbits, and we would expect the small terrestrial planets close to the star, and the massive planets far away from the star. What are we actually finding? New types of planets, planets that are larger than Jupiter. Many planets that are of intermediate size between that of Earth and Neptune, planets that do not exist in our solar system, and hot Jupiters, massive planets that exist very close to their stars. So let's look at these in a chart that we can show here, and we see the exoplanets shown here show size on the y-axis and their orbital period on the x-axis. So we see that rocky planets are very common. In fact, there are a lot more rocky planets than there are other types. Now we can see the rocky planets in yellow here. Lava worlds would be similar to rocky planets except very molten. But when you get up to the giant planets, there are far fewer dots up there, each dot representing a planet. We also see these unusual hot Jupiters. These are up in the corner here, and these are planets that are Jupiter-sized. So Jupiter is this line right here. These are as big as Jupiter, if not bigger. And look at their orbital periods. Here would be an orbital period of about 10 days. Here would be an orbital period of one day. So these things orbit around much faster than things like Mercury, which would be closer to 88 days over here. So they're really massive planets, really close to their stars, and that gives us a good thing to change, something to think about when we're looking at how planetary systems form. We also look at the super-Earths and the mini-Neptunes. These are intermediate-sized planets that do not exist in our solar system. So in our solar system, this is a gap. There are no planets larger than Earth and no planets smaller than Neptune. But look at all the planets that exist there. So why do we not happen to have any of those types of planets in our solar system? Now we can also look at them here by size in a bar graph. Here are the super-Earths and the mini-Neptunes, and that is the vast majority of the planets that we have found so far. In our solar system, we see the range over here and the range over here, and that is it. So it's just very interesting to see that the vast majority of planets that have been discovered so far are not of types that we have in our own solar system. Now part of what we see is a selection effect. So what types of planets can we detect? Radiovelocity and transit methods. These have given us the vast majority of the planets that have been detected. They are very good at detecting large planets that are close to their stars. Large planets will give a stronger radiovelocity shift and will dim more of a planet of a star's surface. So they're easier to detect. They'll also occur more often. We will get the radiovelocity shifts faster and the transit's faster. This introduces a bias toward detecting these types. So maybe we've detected a lot of the hot Jupiters that were in our selection area. And maybe they're not as common as we think because they're just easier to detect. Smaller planets probably exist but really are not yet detectable. Although technist technology increases, we are finding more and more Earth-like planets, but it's still hard to find the smaller ones. Jupiter-like planets at great distances. There aren't a lot of those that we found so far. This problem, we need time. Jupiter around our sun would not be detectable for decades. It would take a long time. It has a 12-year orbit. So if we saw an eclipse today, then we'd have to wait 12 years to see the next one. And then we'd probably want to wait another 12 years to confirm that at least. So we're talking at least several decades, and that's for Jupiter. If things are orbiting even further out, they're going to be really hard to detect by either radiovelocity or transit methods to be able to confirm. So let's look at some of the systems of exoplanets that have been detected. We're going to look at, again, a number of systems with multiple planets. We have the Kepler-90 system that we look at here. The Kepler-90 system does have eight known planets just like our own. However, they all orbit very close to the star. If you'll note here, there are one, two, three, four, five planets here, and then this red circle is number six, and there's two in even closer that are not visible here. So all eight of these planets orbit closer to their system than Earth does in our solar system. So it's interesting to see, again, how close can planets be spaced and the system remain stable? Ours are pretty well spread out. Here we have a lot of planets very close together. We can also look at these a little bit more, and let's take another look at Kepler-90 system. Now, here we're looking at them not to orbital scale but to size scale. These are all big planets. So the largest here is larger than Jupiter, and there's two very large planets. The others here are more of the Uranus or Neptune size, and even the smaller ones are larger than Earth. So it's a very interesting system. Remember that all of these orbit closer to their star than Earth does to our Sun. So we have to start thinking about how that can affect our models of how planets form. We also have the Trappist-1 system, another common one that is talked about, and we have all of those orbits, and if we look at their orbital periods running from one and a half days up to about 19 days. Again, all of those are very close to their stars. Mercury in our solar system is 0.387 AUs. The closest one here, the furthest one is 0.06 AUs. All of these planets are much closer to their star than Mercury. So it's interesting to see how you can form a stable planetary system very close to a star. And several of these are in the habitable zone of that star. Now it's a different type of star than our Sun, but several of these are within the habitable zone of this star, which we can see here, is the green region around it. In our solar system Venus is just off the inner edge. Mars is in the outer region. Earth is right in the habitable zone. Here we have several of these planets that are within the habitable zone of their planet. And that does not mean they have life, but there is the potential for liquid water to be present here. So how does this affect our ideas of how planets form? So how do these change? Well, our solar nebula model does not explain a lot of these things. How does it explain a Jupiter-sized planet forming close to the star? We can't explain that under the condensation sequences. Jupiter-type planets should not form close to the star. So we know that many of them exist, since they do exist they can form, and one thought is perhaps planetary migrations. That planets actually do not form, or have not formed, or are not currently present where they formed. We also detect planets with high eccentricities, not very circular orbits, those orbiting at large angles. So what we don't know yet is our system the unusual one? Are we the odd system? Or are we simply biased towards detecting these other types? Or are these other types really far more common? So here we see several artist's conceptions of a number of these exoplanets that have been discovered. So, what our models show now is that migration may be common, and that even in our system, Uranus and Neptune probably formed closer to Jupiter and Saturn, and then were migrated away. We know that planetary systems are common, very close to stars. Not just the Jupiters, but lots of planets are close to the stars. Why not? What happened to this in our system? One of the problems with our model is that it was based on one system. Ours. And that's not bad. It's simply the only system we had for a long time. Now we know of thousands of systems, and we're starting to get a better picture. It's not clear yet, and it's going to take a lot of studies of these planets to really be able to better understand them. So, we want to talk about one more thing before we finish here, and that is what we mean by habitable planet. A habitable planet means simply that the potential for liquid water to exist on the surface. So, they've got to be similar in size to Earth. If they're a gas giant planet, they're probably not going to have a surface with liquid water. If they're too small, then they're not going to be able to hold an atmosphere and have water. As of this point, we have a dozen or so that have been detected, and more of these are likely.  It simply means that they're in the right range from their star to have liquid water on their surface. And of course, we consider liquid water as important for life. And here we see the artist's conception of a planet around Proxima Centauri B, the closest exoplanet to Earth, only four light years away, which is in the habitable zone around what we call Proxima Centauri, which is a part of the Alpha Centauri system and is actually even a little bit closer right now than Alpha Centauri itself. Now, again, that doesn't mean that there's life there. Again, only that there is the potential for life and potential for water. So let's go ahead and finish up with our summary. And what we looked at this time was that exoplanets are found that are very different from the planets we know in our solar system. We talked about hot Jupiters and other distinct types of orbits that are causing astronomers to rethink the models of planetary formation. And we're also beginning to detect habitable planets, so potential for finding something with life on it. So that concludes this lecture on changing perspectives of planetary formation. We'll be back again next time for another topic in astronomy. So until then, have a great day, everyone, and I will see you in class.


For years I've recommended that the healthiest beverage to drink is tea. Even healthier than water, since tea is all the water of water, yet as a bonus carries a huge load of nutrition without adding calories. But there's a belief that caffeinated drinks, such as tea, may adversely affect hydration. Now this was based on experiments done with high-dose caffeine pills, though, which may not entirely reflect the likely impact of tea, which is a more complex substance. So researchers compared 4 cups of black tea to 4 cups of water and 6 cups of black tea to 6 cups of water. Kept volunteers locked up for 24 hours, so could measure every drop going in and every drop coming out. The test revealed no significant differences between tea and water. For any of the average blood or urine measurements, it was concluded that black tea in the amount studied offered similar hydrating properties to water. Thus, tea could be considered a healthy choice of beverages and health professionals that don't know any better and incorrectly identify tea as a diuretic could be misleading people and serve to drive consumption towards less healthy beverages.


people of the under-25, please put your hands and voices and welcome the man himself, Sadhguru, onto the stage. Keep yourself calm when you want to, like what's that control, what's that switch? If I'm riding or driving, the faster it gets, the calmer and cooler I become. There's only one rule, never collide with anything. This goes for your life also. You don't become significant because you've done something. That is a social significance. That may happen, that may not happen. That depends on the times in which we exist. But if you sit here, it must be significant to be this life. She is more driving towards mukti rather than just material well-being. That's what she designed for. Bhairavi is that, that if you know how to make use of this, being exuberant and wonderful every moment of your life is a living possibility. Today I've made some nice ragi dosa, you must eat and see. I mean, how do you hold on to that joy because... There's nothing to hold on to. If you don't hold on to anything, you'll be joyful. No more, it's dead. I just had a session through the sun. All of you young women here, this is New India, what we're seeing here. If we change the way the young women of this country understand their life, the way they look at themselves and everybody around them and their skill sets become of international quality, then we've changed the nation for sure. Here I am at India-Pakistan border.  But still, we have to guard it. Our brave men and women are doing their best. Thank you, all of you told us. Thank you very much. If the attention is so important, what's the best way to maintain it? Human attention opens up doors like we are never imagined possible. In a sport, it's attention, not memory.  That's what not really what you need out there. What you need is simply attention. One thing, all of you realators, you must understand this. We have only four percent of the world's land, but we have seventeen point two percent of the world's population. In this four percent, how do we build in the smartest possible way? It's very important we learn to build differently. It is very important our building, our housing, our infrastructure suit this nation where we have four percent of the land and nearly twenty percent of the world's population. This is something all of you must keep in your mind. It's a great honor to be here in Beners and also to be talking to the farmers. I am putting this on us and this responsibility and this honor upon you that what you do here in the next two to three years time could be a module for the entire world, could set up a revolution in the world of reviving soils. Go like you currently and say this is new fashion in the future life. This is the forty-second struggle. It's my vision, my blessing.  Thank you very much. Our three wonderful swamijis who are here, they represent institutions and traditions, each one of them. Each institution is over a thousand years old. I'm the only one without a pedigree here. This saint never rests. I'm the only one who can be a saint or a saint. That is the foundation of Isha, the centre of the Mahatma. Many countries in India don't have the right to write in foreign languages. But our Indian country, even the people who live in other countries in the world, don't have the right to write in foreign languages. He is very grateful to you for this opportunity to be here in Ashram once more again. He came with the friends. She is blind as well. I am being brailed, all right? The only thing that we need to do is conduct ourselves. If we can conduct this consciously, we are a solution for everything.