Extras
    
Astronauts and Mission Control relive terrifying moments during construction of the ISS.
          
          
            
                
                    
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                    S52
                
            
            
                
                  E19
                
            
            
                
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        Dive into how Earth’s weirdest microbes could help us spot extraterrestrial life.
          
          
            
                
                    
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                  1:11:15
                
            
          
        Find out why deadly flash floods are on the rise and how we can protect ourselves from them.
          
          
            
                
                    
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                    S52
                
            
            
                
                  E18
                
            
            
                
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        Explore mysterious 9,000-year-old Stone Age megastructures found in the Arabian Desert.
          
          
            
                
                    
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                    S52
                
            
            
                
                  E17
                
            
            
                
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        What is speech, really? Neuroscientist Erich Jarvis explores the science behind how we speak.
          
          
            
                
                    
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                  1:03:49
                
            
          
        Discover how two revolutionary ancient inventions changed the course of humanity forever.
          
          
            
                
                    
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                    S52
                
            
            
                
                  E16
                
            
            
                
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        Follow ancient humans’ journey into an icy and perilous new land.
          
          
            
                
                    
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                    S52
                
            
            
                
                  E15
                
            
            
                
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        Your brain does all kinds of strange things. Neuroscientist Heather Berlin explains how it works.
          
          
            
                
                    
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                  1:28:59
                
            
          
        Discover how Homo sapiens outlasted Neanderthals – and how they helped make us who we are today.
          
          
            
                
                    
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                    S52
                
            
            
                
                  E14
                
            
            
                
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        Follow Homo sapiens as they venture out of Africa and spread farther than any other human species.
          
          
            
                
                    
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                    S52
                
            
            
                
                  E13
                
            
            
                
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                  0:30