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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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52:31
What led to the devastating floods that Hurricane Katrina unleashed on New Orleans?
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53:31
Journey back to the beginning of everything: the universe, Earth, and life itself.
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50:52
Journey back to the beginning of everything: the universe, Earth, and life itself.
Unlock with PBS Passport
51:52
Journey back to the beginning of everything: the universe, Earth, and life itself.
Unlock with PBS Passport
53:50
An American combat hospital mobilized in Iraq faces a daily drama of wartime treatment.
53:06
Will experimental particle physics confirm the wild predictions of string theory?
52:56
Do miniscule vibrating strands of energy hold the key to a unified theory of physics?
52:55
Combining the laws of the universe in one theory that explains it all is the Holy Grail