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This NASA Scientist Helps Prevent Mars from Contamination
The spacecraft has to be extremely clean. The entire spacecraft—that includes the rover, the heat shield, the descent stage, and back shell—must contain less than 500,000 bacterial endospores, or spores. Just to give you an idea, a teaspoon of seawater has ten times more bacteria.
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53:25
Surprising evidence at the world’s oldest temple overturns our understanding of human history.
53:38
Explore mammals’ surprising origins, long before the age of dinosaurs.
53:39
Do speech buttons really allow dogs to talk to us? Scientists investigate.
53:39
New evidence sheds light on the remarkable life—and mysterious collapse—of the ancient jungle city.
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53:31
What if violent asteroid impacts actually jump-started life on Earth? Explore a dramatic theory.
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53:41
See how ingenuity and teamwork keep the crew alive and doing science 250 miles above Earth.
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53:40
Astronauts and Mission Control relive terrifying moments during construction of the ISS.
53:28
Find out why deadly flash floods are on the rise and how we can protect ourselves from them.
53:21
Explore mysterious 9,000-year-old Stone Age megastructures found in the Arabian Desert.
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53:32
Discover how two revolutionary ancient inventions changed the course of humanity forever.
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53:25
Follow ancient humans’ journey into an icy and perilous new land.
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53:27
Discover how Homo sapiens outlasted Neanderthals – and how they helped make us who we are today.