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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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53:21
Can bringing predators—and fear—back into an ecosystem help restore its natural balance?
1:52:46
Paleontologist Kirk Johnson explores the dynamic history—and future—of ice at the poles.
53:30
Discover the science behind Leonardo da Vinci's masterpieces—and Mona Lisa's iconic smile.
53:15
Amazing fossils reveal how mammals took over after an asteroid wiped out the dinosaurs.
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53:32
Discover why scientists and entrepreneurs alike have their sights set on the Moon again.
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53:23
New archeological evidence shows the stunning engineering of the Great Pyramid of Giza.
53:51
Join scientists as they grab light from across the universe to prove quantum entanglement.