Astronomers Carl Sagan and George Mullen discovered a puzzling contradictions in 1972. They called it the Faint Young Sun Paradox. It is generally understood that there must have been water early in Earth's history in order to spawn life. But, it is also accepted by scientists that the sun was dim in the early years, and not hot enough to make Earth a cozy, warm place ripe for life. So what gives? Hear about this paradox and more in the videos below. (By the way, scientists in the past few years think they may have found a solution.)
The Faint Young Sun Paradox
Life on Earth should have been impossible given what we believe about the sun.
The Relativity Paradox
If you're in the mood for a headier paradox, here ya go!
3 Time Travel Paradoxes
As much as you may want time travel to exist, you have to admit there are a lot of obstacles in making that logic seem reasonable.
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