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Course: Big History Project > Unit 1
Lesson 1: Welcome to Big History | 1.0- ACTIVITY: Easter Island Mystery
- READ: What Happened on Easter Island?
- ACTIVITY: Unit 1 Vocab Tracking
- WATCH: Unit 1 Overview - What Is Big History?
- WATCH: What Is Big History?
- WATCH: The Big Bang
- WATCH: A Big History of Everything – H2
- Quiz: Welcome to the Big History
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WATCH: Unit 1 Overview - What Is Big History?
What is Big History? This is the first of 10 videos orienting you to the 10 units of the Big History Project course. Big History teacher Rachel Hanson helps us see how science is linked to the study of history, and why it’s important to examine our Universe’s 13.8 billion years of existence to see how our understanding of this history has changed over time. Like what you see? This video is part of a comprehensive social studies curriculum from OER Project, a family of free, online social studies courses. OER Project aims to empower teachers by offering free and fully supported social studies courses for middle- and high-school students. Your account is the key to accessing our standards-aligned courses that are designed with built-in supports like leveled readings, audio recordings of texts, video transcripts, and more. Register today at oerproject.com!
Website: https://www.oerproject.com/Big-History
Facebook: https://www.facebook.com/OERProject
Twitter: https://www.twitter.com/oerproject/. Created by Big History Project.
Website: https://www.oerproject.com/Big-History
Facebook: https://www.facebook.com/OERProject
Twitter: https://www.twitter.com/oerproject/. Created by Big History Project.
Want to join the conversation?
- I also wish I had a time travelling machine so that I can explore the universe, watch the big bang happen and even go to easter island🗿 to figure out the mystery.
Now how does one go about building a time travelling machine?(2 votes) - https://www.khanacademy.org/humanities/big-history-project/what-is-big-history/welcome-to-big-history/v/watch-unit-1-overview-what-is-big-history#:~:text=Where%20do%20we%20come%20from%3F%20Where%20are%20we%20going%3F%20Who%26nbsp,know%20about%20999%20paperclips%20ago.%20Wish%20I%20had%20a%20time%20machine.(2 votes)
- GUYS
I have something to share
Asking a question in Kahn Academy is pointless! Even if someone replies, how do you know without going back? You'll be disappointed when someone doesn't reply until 8 years later (Trust me, I've answered 10 yr old questions)
Sorry if this came out rude, but maybe Google could serve you better!
Hope I can help you!(1 vote) - Oml at the end when she said "999 paper clips ago" it reminded me of how many paper frogs are in my closet to break the world record (2,500)(1 vote)
- how do you know how old the earth is?(1 vote)
- As advances in chemistry, geology, and physics continued, scientists found a method by which the absolute age—an actual number of years—of a rock or mineral sample could be determined. This method is called radiometric dating, and it involves the decay, or breakdown, of radioactive elements.
Using radiometric dating techniques, it became possible to determine the actual age of a sample.
Radiometric dating requires an understanding of isotopes. Isotopes are variations of an element differentiated by the number of neutrons in their nuclei. The isotopes of unstable radioactive elements—known as parent isotopes—eventually decay into other, more stable elements—known as daughter isotopes—in a predictable manner, and in a precise amount of time called a half-life. The half-life of an element is the amount of time required for exactly half of a quantity of that element to decay. The age of a sample can be determined based on the ratio of parent to daughter isotopes within the sample.
One problem with this approach to dating rocks and minerals on Earth is the presence of the rock cycle. During the rock cycle, rocks are constantly changing between forms, going back and forth from igneous to metamorphic to sedimentary. Old rocks may even be destroyed as they slide back into Earth’s mantle, to be replaced by newer rocks formed by solidified lava. This makes finding an exact age for Earth difficult, because the original rocks that formed on the planet at the earliest stages of its creation are no longer here. The oldest rocks that have been found are about 3.8-billion years old, though some tiny minerals have been dated at 4.2 billion years.
To get around the difficulty presented by the rock cycle, scientists have looked elsewhere in the solar system for even older rock samples. They have examined rocks from the moon and from meteorites, neither of which have been altered by the rock cycle. The same techniques of radiometric dating have been used on those rocks. All the data from Earth and beyond has led to the estimated age of 4.5 billion years for our planet.(1 vote)
- Cool. This is going to be a long unit! I hope this isn't going to be that long. OH I'm so glad that I read my entire library in my room to get ready for this. But I'm in 7th grade. But I never got to do social studies last year so I never got to learn about the ancient world and because of a stupid disabled bus when I'm not handicapped, and I'm in public school, Kalispel Middle School. If your wondering! I told my mom that this program is for homeschoolers but mom says that this program is for everyone!!(1 vote)
- how History is written, oral or drawn record of the past. It is kept so that other people later in society can learn from it?(1 vote)
- what are you doing Carlos?(1 vote)
- History is a written, oral or drawn record of the past. It is kept so that other people later in society can learn from it.(1 vote)
Video transcript
Where do we come from? Where are we going? Who are we? If you ever looked up into the sky at night and asked yourself any of these questions, you're not alone. I don't have all the answers, unless your question is "Who is that?" which I totally know. I'm Rachel Hansen. And while I can't predict the future, I do know that
you'll be seeing me nine more times this year in each unit overview to learn about something we
call Big History. Ever since we developed language, humans have been telling each other stories about the origins of the world and our place in it. These origin stories all try to do something
similar, they seek to tell the listener that there's some sense to it all, that the universe has
structure, and that we fit into it. Different people tell many different stories about the past.
In the Big History Project we call them narratives. Depending upon what your evidence tells
you and which elements you highlight your narrative will change. There's no single story
about past events that can tell us everything. For example, think about the last time you had
an argument with a friend. Afterward, did you both agree about who was right and who was wrong? Did you both remember your fight the exact same way? Did you both bring up the same evidence
to show that you were right? I'm guessing probably not. I'm guessing you both had two
very different narratives about that past event. That's a small example, but in Big History we have
a really big narrative about the universe and our place in it. It starts 13.8 billion years ago with
the big bang and continues into the distant future. To support this narrative we'll be using a lot of
historical evidence but our narrative starts long before humans even existed. So we'll often look to science for our evidence. Our course is divided into 10 units you'll see me in an introductory
video like this at the beginning of each unit. But the narrative of this course is also marked
by eight thresholds of increasing complexity, or just thresholds. I know! Ten units?! Eight
thresholds?! What?! But just think of it this way: the ten units are like chapters in a book. They divide the big history story into blocks of time that will help us organize things. The eight thresholds, on the other hand, are crucial turning points in the big history narrative when something really big changed. Something like the sun was born or living things exist now. Some units have multiple thresholds and some have none As we move through the 10 units of this
course we'll explore these eight thresholds of increasing complexity as we try to
understand how we got to where we are. [instrumental music] Oh! It's time for questions from the audience! Which is weird, because this is pre-recorded. [laugh track]
The first question is What's all this science doing in my
history class? And this one says Why do i have to learn history to understand astrophysics? Two very good questions from two very inquisitive students. Well, in these ten overview videos i'm going to
help you answer both of those questions. As we move through the course, I'll help you understand how
we know what we know. And we'll also investigate how people living in many periods have changed and deepened their understanding of the universe and everything in it. That's the history part. And
yes, okay, for a history class it might seem like a lot of science talk, but it's still history! Science might seem like an unchanging story. Stuff like, the law of gravity sound pretty darn permanent,
and historians can't change how gravity works. [Marker thuds on floor] Every time. But, our understanding of gravity
can change because we're humans. We've got these squishy little brains filled with funny ideas
and nagging questions. How humans understand and explain the world around us changes all the time. And it's changed a ton in the last few thousand years. Reshaping how we interact with our world
and the stories we tell about our place in it. That's why history and science go together
like peanut butter and jelly or like flannel and Fridays. We think you'll understand humanity's
place in this universe better if you learn how we fit in with all the supernovae black holes, quarks,
and chemical compounds that make it up. but we also think you'll understand all those sciency bits
a little better if you understand the history of human thought. From how our ancestors explain the
origins of their world to the scientists using a telescope the size of a school bus to peer back in time at the explosive origins of our universe. [instrumental music] In Unit 1 you're going to learn about some big stuff. But you're also going to encounter some teeny tiny
stuff like atoms and molecules. So, you'll need to learn how to zoom out to identify big patterns
and zoom back in to comprehend smaller changes. That's called scale switching, and it's an
important tool in your historian toolbox. Next, you'll dive into some narratives that
people in the past have used to explain the existence of life, the universe, and everything. You'll compare these ancient origin stories with the modern scientific origin story offered by Big History. Finally, you'll meet historian Bob Bain, who will introduce you to one of the most important tools of a historian: claim testing. How do we know what we know? And
how do we choose which narratives to believe? You'll learn how to use intuition, logic, authority, and evidence to evaluate claims made by others. Understanding chemistry, astrophysics, forensics,
archaeology, and a bunch of other schools of thought will give you
more evidence to examine historical claims. That's another reason we've put all this science
in your history class. Some historians think of history only in
terms of recorded history, meaning that it started only five thousand years ago when we
started writing things down. But look at this. This paper clip represents five thousand years.
That's all recorded history. All the clay tablets, Egyptian hieroglyphics, Greek plays, Chinese
philosophy, all the religious texts ever written, all your favorite novels, all the social
media posts. It all fits in these 5,000 years. In this one inch. Get ready for some scale switching. I would need 50 paper clips to get to 250,000 years, which is how long our species has been on the planet. To represent the 4.56 billion years our planet has existed, I'd need over 14 miles of paper clips. That's longer than the island of manhattan! And to reach 13.8 billion years, the age of our universe, my paper clip chain would stretch 43.5 miles, stretching across the state of
Delaware and into the Atlantic ocean. That's an awful lot of time that recorded
history leaves out. If we only pay attention to what's been written down we lose a lot
of the rich diversity of human experience. We also miss the connections between our universe,
solar system, planet, and us. comprehending the origins of the universe requires the tools
of chemistry and physics and a bunch of other disciplines. But we'll also need the tools of
the historian like scale switching and claim testing if we're going to understand how
we know what we know and why that matters. Okay that's 1,000 paper clips just 2 million
759,000 more to go to get to 43 and a half miles. It's gonna be a long night. Hey! I'm clipping here! What?! We can do the paper clip thing with CGI?! Well, that would have been nice to
know about 999 paperclips ago. Wish I had a time machine.