13.7: Cosmos And Culture13.7: Cosmos And Culture

Commentary On Science And Society

When the Galileo spacecraft swooped by Jupiter's frozen moon Europa in Nov. 1997, views of its blistered surface strengthened suspicions that a briny ocean harboring life could lie beneath an icy crust. AP hide caption

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In this composite image, the sun has reached its northernmost point in Earth's sky, marking a season change and the first solstice of the year 2004. NASA/ESA hide caption

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Earth has been many different planets in its long history — and could be more. Some imaginary views are shown here. Top (from left): a water world before large-scale continents had formed; a "snowball" Earth phase with extreme glaciation; and a world shrouded in smoke after a large asteroid impact. Bottom: Earth today; Earth losing its oceans as the sun becomes hotter; and a final scorched Earth. Courtesy of Don Brownlee, University of Washington hide caption

toggle caption Courtesy of Don Brownlee, University of Washington

An artist's concept depicts one possible appearance of the planet Kepler-452b, the first near-Earth-size world to be found in the habitable zone of a star that is similar to our sun. NASA Ames/JPL-Caltech/T. Pyle hide caption

toggle caption NASA Ames/JPL-Caltech/T. Pyle