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Big History Project
Course: Big History Project > Unit 2
Lesson 1: The Big Bang | 2.0- WATCH: Unit 2 Overview - The Big Bang
- ACTIVITY: Unit 2 Vocab Tracking
- WATCH: A Big History of Everything
- READ: Complexity and Thresholds
- WATCH: Threshold 1 —The Big Bang
- ACTIVITY: This Threshold Today
- WATCH: Questions About the Big Bang
- ACTIVITY: Threshold Card — Threshold 1 The Big Bang
- Quiz: The Big Bang
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WATCH: Unit 2 Overview - The Big Bang
As you begin Unit 2 of the Big History Project course, this overview reminds you that the Big Bang Theory was definitely a thing before that TV show, and that the world’s greatest historians have always been largely dependent on the world’s greatest scientists. Discoveries on multiple continents over thousands of years have allowed humans to build the knowledge—and the process of testing that knowledge—that we have today. 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
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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.
Video transcript
Hello! This is a time machine.
And for today's lesson I'm going to take us back. Back 13 billion years. [whirring noises] Unfortunately, the maximum it can go is four
seconds so I'll just be really descriptive. [instrumental music] Hi, I'm Rachel Hansen. And this is Unit 2
The Big Bang. Check this out. This picture may be the closest thing we have to a time machine because it's showing us something from 13 billion years ago. How? Well, not by using an ordinary camera. This image was taken by the Hubble Space Telescope in 2003. There are 10,000 galaxies in this picture. Some of those tiny red ones are so far away that the light from them that's reaching us today is
from, yes, 13 billion years ago. This picture lets us peer back into the earliest days of our universe.
And this is only a sliver of our night sky. If you were standing on earth and looking up this image
occupies a space just one tenth the size of the full moon. To make this one tiny picture of
our unimaginably huge universe it took hundreds of scientists and engineers, 400 orbits around
earth, four months, and one awesome telescope. But it also took thousands of years and
generations of thinkers taking chances, making mistakes, and progressing our understanding
of the size nature and origins of the universe. Edwin Hubble, that's the guy who the telescope is
named for, first proved in 1924 that other galaxies existed. He showed us that the universe
was so much bigger than we thought. But he didn't stop there. In 1929, he formulated Hubble's Law. Not the kind of law where you get in trouble for breaking it, but one of those "This
is just how it is" laws. Hubble's law helped provide evidence that the universe is expanding. His work supports a theory proposed by Georges Lemaitre just two years earlier. the Big Bang Theory. [instrumental music] That probably sounds like way too much science for a history class. But that's like saying
that a history of Rome has too many Romans. Science is a part of history. And history
can help us explain how we know what we know. It shows us how science changed over time. And it can reveal how changes in our knowledge transformed our societies. Take Edwin Hubble. It's thanks to his
discoveries that we understand the size and origins of our universe. But he built on the ideas and discoveries of other
astronomers in the early 20th century. like Henrietta Levitt, Albert Einstein,
Harlow Shapley, and Georges Lemaitre. And these scholars built on the work of
scholars from centuries earlier Ancient Greeks like Claudius Ptolemy asserted
that the universe revolved around the earth. Generations of Arab, Persian, Chinese, and other
astronomers improved on Ptolemy's calculations. Then, in the 16th century, Nicholas Copernicus asserted that, actually, the sun sat at the center of the cosmos. Everyone was like, "Wait, what?" From there, step by step, discovery by discovery we moved closer to the understandings that
allowed Hubble to make his breakthrough. And his breakthroughs allowed later
astronomers to improve on his work, and develop new ideas and discoveries, refining
our understanding of space-time, the earliest days of our universe, and how to capture a
picture like this. Even today, our understanding of the beginning of time in our universe continues to evolve with each new discovery. [instrumental music] In Unit 1, we defined Big History. It's the modern scientific origin story backed by historical and scientific evidence that tells the history
of the universe and our place in it. You learned that this class is about the history of human thought. If this were a science class, we'd teach what
scientists discovered and how they did it. But this course, this history course, is about learning how our knowledge of the universe
and everything in it has changed over time. That means that, sometimes, we'll need some
knowledge of scientific concepts. So, while this unit may seem like it's all about the Big Bang, it's really about the way humans have answered the question: Where did we come from? In the first unit, we also examined the concept of scale and how our perspective changes whether we're zooming in on a tiny grain of sand or out to an entire planet. Then we explored how different human
societies explain the origins of our world. We also learned about claim testing and how
you can evaluate the narratives you encounter. And finally, we met eight new friends,
the thresholds of increasing complexity. Each threshold marks a moment in time when
just the right ingredients came together under just the right goldilocks conditions to
create something more complex in our universe. The Big Bang is the first threshold of increasing complexity. [instrumental music] What is the Big Bang? And how do we know
that it's the origin story of our universe? Those are the two big questions you'll tackle
in this unit. The Big Bang is a scientific theory. It claims that the universe started out
incredibly, unimaginably small, hot, and dense. Then, for some reason we still don't know, it
rapidly expanded. This was the beginning of time and space
and everything else in our universe. all the ingredients for stars, planets, mountains, polar bears, daffodils, and your lunch were born in this instant. But, how did scientists come up with the theory? It took centuries of careful observations, the development of new technologies, and new ways of
thinking to get a 21st century model of our universe. In this unit, they'll travel back in time to meet scholars like Ptolemy Nasir al-Din al-Tusi, Copernicus, Galileo, and Hubble. You'll ask how each explained the origins of the universe and how each built on older knowledge to
update our modern scientific origin story. The way that humans build and improve on knowledge
over time is called collective learning, and you're going to hear a lot more about it throughout this course. And guess what, we still don't know everything. Each generation of scholars continues to build on the past. In this unit, you'll also see how different disciplines
study the origins of the universe in different ways. Scholars from a wide variety of disciplines
such as physics, astronomy, cosmology, chemistry, geology, biology, and history have all helped
us understand the universe and our place in it. That's a lot of information in one short video. So let's do a quick recap. Big History is organized around eight thresholds of increasing complexity. And the first is, say it with me, the Big Bang. Now, we don't know a lot about what happened
before the big bang, but we do have a lot of evidence about what happened in the moments just after as the universe was born, expanded, and cooled over time. We also have centuries of scholarly works on the history of the universe. these scholars are legitimate authorities, who used
evidence to develop ideas that were then shared, tested, and improved upon by other scholars
over time. I don't want to brag, but I just name dropped not one, but two claim testers, evidence and authority, to help explain the Big Bang. As you go through the lessons in this unit,
think about the evidence that supports the Big Bang Theory. Also think about the authorities who support,
extend, or challenge this evidence. Then, as you move through the unit put
the evidence and authority together with your intuition and logic to evaluate the Big Bang Theory. When you use all four of the claim testers to
evaluate a particular topic you're well on your way to becoming a big historian. I wonder if this thing can go four seconds into the future. [whirring noises] [instrumental music] It worked! What did I miss?