The faint young Sun paradox or problem describes the apparent contradiction between observations of liquid water early in the Earth's history and the astrophysical expectation that the Sun's output would be only 70% as intense during that epoch as it is during the modern epoch. The issue was raised by astronomers Carl Sagan and George Mullen in 1972. Explanations of this paradox have taken into account greenhouse effects, astrophysical influences, or a combination of the two.
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Famous quotes containing the words faint, young, sun and/or paradox:
“That faint semblance of Eden, the picnic in the greenwood.”
—Herman Melville (1819–1891)
“Meek young men grow up in libraries, believing it their duty to accept the views which Cicero, which Locke, which Bacon, have given, forgetful that Cicero, Locke, and Bacon were only young men in libraries, when they wrote these books. Hence, instead of Man Thinking, we have the book-worm.”
—Ralph Waldo Emerson (1803–1882)
“He will watch from dawn to gloom
The lake-reflected sun illume
The yellow bees in the ivy-bloom,
Nor heed nor see, what things they be;
But from these create he can
Forms more real than living man,
Nurslings of immortality!”
—Percy Bysshe Shelley (1792–1822)
“A good aphorism is too hard for the teeth of time and is not eaten up by all the centuries, even though it serves as food for every age: hence it is the greatest paradox in literature, the imperishable in the midst of change, the nourishment which—like salt—is always prized, but which never loses its savor as salt does.”
—Friedrich Nietzsche (1844–1900)