let's talk about Galileo okay let's talk about Galileo how many of you have ever heard of Galileo have you heard of Galileo yes or no yeah you probably have heard of Galileo Galileo is is one of the ones just normal normal people have heard of before he's so famous that we just say one name and Galileo that's his first name right that's his first name right there okay he's so famous that you say his first name and people are like oh yes is this guy is this that Galileo I know which one I know which Galileo you're talking about and you guys know what Galileo's last name is anybody know what Galileo's last name is to me it's kind of funny so Galileo's last name is Galilei II if you take his first name and change the last letter to an AI that's his name galileo galilei ii so to me to me the reason I find that funny is to me that means his parents were like really lazy when they were naming I don't I don't know anything about like Italian naming conventions at the time I'm probably talking you know out the side of my neck here but Galileo Galilei II that's to me that's like if you're if your parents were mr. and mrs. Smith and they were like oh no we had a baby oh oh no we had a baby we got a named him now uh spit Oh Smith his name is Mitch Oh Smith that's that's what it's in my head that's what his parents did when they named him they were like I don't worry he won't be famous it's fine just nobody'll notice and then oh he got famous right so Galileo goofy name we're just gonna say Galileo I hope that one name one day people can just say my first name and they know in like a hundred years from now they like oh yeah I know which one you're talking about it was that guy right that's Galileo okay now does anybody know what Galileo is famous for inventing what's Galileo is famous for inventing here's a hint telescopes yes up until this point all throughout history all of astronomy was just done with the naked eye and so there was a big limit to to how good our measurements could be and how good our data could be but with the invention of the telescope here Galileo was able to see things that no one had ever seen before okay now there is a little bit of a contention there he might not have technically invented the telescope even though he gets credit for it it turns out there was a he lived down the street from a watchmaker and are like a clock maker and if you're a clock maker you have to work with tiny little pieces all the time and it would be nice if you could see them up a lot bigger and this watchmaker down the street had lined up a few lenses in a row like kind of like in a line and he used that and he basically had a tube with two lenses in it and if he looked through it he could see his watch pieces much much larger okay and that guy lived down the street from Galileo so there's some speculation that Galileo might might have ended up seeing this neighbor down the street and essentially like Oh what are you doing with that and he just like telescope we don't know if that happened but it seems a little suspicious that a guy down the street from him had invented almost the same thing for looking down and Galileo could just tilt it up and be like Oh telescope I invented a new thing by picking your thing up and pushing it that might have happened right that said the the watchmaker didn't know what he was on to so technically it's sort of a new invention even if that happened because he's got a whole new use for it but yeah oh and somebody mentioned yeah Galileo if you just invented the telescope what are you gonna look at it with it everything right you're gonna look at pretty much everything in the sky he looked at the moon he looked at the planets he looked at the stars and unfortunately one thing he looked at as he probably looked a little too close to the Sun and it's speculated that that possibly may have been what made him go blind just looking like he probably wouldn't have looked right at the Sun if you look right at the some of the telescope it will literally burn a hole in your eye so don't do that fun fact public safety announcement don't look at the Sun you could go blind like Galileo okay now so it was Galileo with his telescope that finally found proof that the planets went around the Sun okay so let's talk about that real quick how did he prove it well he saw a lot of things that that helped him believe that the Sun was at the center of the solar system and I'm gonna talk about them in increasing importance okay because he looked at the Stars if you look at the stars through a telescope like Galileo's they look exactly the same because stars are so far away that even if you magnify them they don't look any different so he wasn't super excited about that that didn't really help him prove that everything was orbiting around the Sun but one thing he looked at was at the moon okay he looked at the moon and up until this point we knew there were splotches on the moon but we didn't know what they were when he looked at the moon through a telescope what did he see what did he see in that telescope what did he see on the moon craters yes he saw craters he saw mountains he saw valleys and don't overthink this where is a another place that has mountains and craters and valleys and things like that what's another place that has those same kind of features other than the moon earth exactly so up until this point we weren't exactly sure what the moon was but Galileo with his telescope saw that the moon was just another place like Earth that doesn't prove anything about planets going around the Sun but the whole idea that everything orbits around the earth kind of comes from everybody thinking the earth was super unique that everything else out there was was was was weird other little dots and everything orbits the earth because the Earth's unique what he saw on the moon showed him that the the moon was a lot like Earth so Earth wasn't so special right now the next thing he looked at it was kind of in that same same wheel box as he looked at the planets and saw through his telescope that they also looked a lot like Earth so the moon and the planets he was the one to discover that the planets were not stars okay he was the one to discover that the planets were things like earth not like those little dots that were further out okay and again that meant that earth was not unique it was just one of many things that were all very similar okay so why would everything orbit around the Earth if there was a bunch of other things right there that are basically the same kind of thing okay that's important the next thing he looked at was Jupiter okay the next thing he looked at was Jupiter and through his telescope he saw something next to Jupiter that no one had ever seen and that was four little dots when he's on Jupiter he saw Jupiter kind of big in his view and he saw four little dots and he watched those four little dots for week after week after week and every every week he drew another picture of where the dots were this is Galileo's actual notes here I believe from week to week to week to week I assume he could read this handwriting I can't read anything up here other than I'm pretty sure this is the word Jupiter right here but I'm not really even sure but and in each of these pictures that's Jupiter and that's the little dots right next to Jupiter and as you can see here these dots sometimes they're on one side of Jupiter sometimes they're on the other side of Jupiter they go back and forth next to Jupiter so check it out can anybody figure out what those little dots are what are those little dots he saw swinging back and forth next to Jupiter what are these dots yeah those are moons he was the first one to discover that other planets have moons okay these dots next to Jupiter saw proved that not everything was orbiting around the earth because you can watch these things orbit Jupiter right now again that doesn't prove anything is orbiting around the Sun but it does prove that Earth wasn't the only thing that stuff was orbiting around which again weakens the idea that we're the center of everything so again looking at the moon and the planets showed that Earth wasn't unique physically and looking at Jupiter in discovering moons showed that Earth wasn't unique in having things orbiting it okay but the most important thing he saw the final thing he saw that really got him excited was what he saw when he looked at Venus okay and we're almost done for the day we got one more thing to talk about after this what did he see when he looked at Venus check this out final drawing of the day oh did it reboot there we go okay when he looked at Venus with the naked eye Venus looks like a dot all the time but sometimes Venus would look like a dot like a circle but sometimes when he looked at Venus it was bigger and it was a perfect half circle well it froze on me let me restart it sometimes when he looked at Venus it was bigger and a perfect half circle and sometimes it would be that same size but it would be the other half of the circle and sometimes it would be just like a sliver of a circle but it would be way bigger so these are all the shapes that that that Venus can have if you look at it through a telescope tiny and a circle a little bit bigger and a half circle and a really big and just a little sliver of a circle okay and what this is what's another thing that has shapes like this what's another thing that makes these same kinds of shapes what's another thing what else makes these shapes like a physical thing you could go look at the moon right it's the moon but there's a difference so the moon has phases like this Venus has phases okay and the difference is the moon doesn't change size when it changes shape okay so so Venus is phases change size this right here is proof that Venus orbits the Sun okay this right here is proof that Venus orbits the Sun how is it proof check this out in the old system everybody orbited the earth okay everybody orbited the earth but if everybody's orbiting the Earth then that means if Earth is here and the Sun is here here's Venus going around its goofy little epicycle that glass ball on the glass ball would Venus ever light up fully from our point of view if we're looking at it from back here we're always gonna see the shady side of Venus we would never see Venus go full in order for Venus to go full where would it need to go where would Venus need to go for us to see Venus light up where would Venus have to go yeah if it stayed over here it would always look dark yeah Venus would have to go back here for the Sun to light it up for us to see it down there right so in order to get the shapes that I was talking about Venus has to go around the Sun so if Venus was right here when it's close to us it would only have a sliver lit up right and when it's really far away on the other side of the Sun it would look fully lit up so it would be a circle but what would the size be like if it's all the way on the other side of the Sun it would be small right so that means the only ways that Venus can always have the same size and shape that Galileo saw it would have to go around the Sun so that means with that telescope you've proven that Venus goes around the Sun because you literally can watch it go around the Sun so out of everything that Galileo saw this was absolute proof that the planets go around the Sun okay so Galileo proved it and anybody could look through his telescope and see the proof anybody could watch the planets go around the Sun so Galileo got excited he's like oh man I have absolute proof that anybody can look at and see and and and they would have to believe that everything goes around the Sun did it work out that way is that how things worked out when Galileo told everybody Hey look you can watch the planets go around the Sun whether you look through my little - did everybody believe this is that how that went down no no no no no no no it absolutely did not go down like that um does anybody know what happened to Galileo when he told everybody about his discovery about his proof he was arrested he was arrested he was placed under arrest for the rest of his entire life okay his entire life he was never freed again so even though Galileo finally had the proof that everything orbited the Sun nobody believed he was like you could just look through the tube and look at it and they're like but I don't have to look through the tube do I you can't make me look through the tube he's like but you just look and you can see it and they're like mmm you know what I'm not even gonna look at it ha ha ha we defeated you Galileo and so he was placed under arrest they actually punished his family for being related to him they punished his family for being related to him they hated him so much that they wanted to make sure they wiped out his bloodline so his daughter for example was actually required to be a nun for the rest of her life they sent her into the mountains so that she would not find any any anybody to have a family with they wanted to make sure she didn't have kids so Galileo's bloodline was cut off because they prevented his kids from having kids okay that's how much they hated this idea which is which is crazy to me and a little while after he died slowly over the next couple of decades more and more people started looking through the telescope and be like oh oh wait oh oh I see it I see oh yeah you're right you dude you see it you could you could just look through this and you could see you could just watch the planets go around the Sun oops um sorry Galileo sorry we did that to you uh you were right uh but they couldn't cuz he was dead then he was dead before you know thinking that nobody would ever believe him and in fact it was the people who put him under arrest was the Catholic Church they did eventually apologized to him after he was dead does anybody know when the Catholic Church apologized to Galileo guess it was the 1990s the gift Galileo is forgiven by the or they Galileo wasn't forgiven but they apologized to Galileo in the 1990s ok up I didn't mean that the church didn't believe him until the 1990s they just didn't officially apologize him until the 1990s they everybody believed that that we were orbiting around the Sun a long time and I don't want to like single out the Catholic Church I mean you know basically everyone Protestants non-christians nobody believed him at the time but eventually I just thought that was a weird fact there ok