Christopher Flavin said over 40 percent of the new generating capacity added in the U.S. last year is from wind power. It's surpassed a little by natural gas.
Earth's Arctic and the Antarctic are very different kinds of places - but if these polar animals switched habitats, penguins might struggle, and polar bears might thrive.
Jupiter is the biggest planet in our solar system, but it isn't massive enough to be a star. Stars require a certain amount of mass to spark thermonuclear fusion - in other words, to shine.
Monarch butterflies of eastern and central North America migrate each fall, over great distances, to the same winter homes of their great-great grandparents.
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