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NOVA
Why Do Comets Have Tails?
Worlds that exist close to the warmth of the sun, like the rocky worlds of Mars, Earth and our moon, have relatively little ice, because they lie inside what is known as the ice line.
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53:40
Take a wild ride into the quantum realm, where even the impossible seems possible.
53:40
It defines our lives, but what is time really? Have a look into its true nature.
53:40
Surprising clues indicate that space is very much something and not nothing.
1:43:15
We are on the verge of answering one of the greatest questions in history: Are we alone?
1:52:42
The story of how African-American Percy Julian defied the odds to become a famous chemist.
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52:31
What led to the devastating floods that Hurricane Katrina unleashed on New Orleans?
