A section of the Sutter's Mill meteorite, dubbed "Darth Vader," is studied at a lab at the University of California, Davis. The meteorite is made of carbonaceous chondrite, which contains materials that formed the planets of the solar system.
The fossil remains of Dickinsonia, an Ediacaran organism that's long been extinct. Scientists have long assumed these early life forms lived in the sea, but a new study argues they emerged on land.
Delegates attend the last day of the U.N. climate talks in Doha, Qatar, on Friday. U.N. climate negotiators locked horns on the final day of talks in Doha to halt the march of global warming, deeply divided on extending the greenhouse gas-curbing Kyoto Protocol and funding for poor countries.
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A boat skims through the melting ice in the Ilulissat fiord, on the western coast of Greenland, in 2008. The glacier is the most active in the Northern Hemisphere, producing 10 percent of Greenland's icebergs, or some 20 million tons of ice per day. But experts say the glacier is in bad shape because of climate change.
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A general view of the Aletsch Glacier on April 21, 2007, near Brig, Switzerland, the largest glacier in the Alps. Unseasonably warm weather with temperatures up to 77 degrees Fahrenheit across Switzerland let snow melt, even at Alpine altitudes.
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This Sept. 16 image released by NASA shows the amount of summer sea ice in the Arctic, at center in white, and the 1979 to 2000 average extent for the day shown, with the yellow line. Scientists say sea ice in the Arctic shrank to an all-time low of 1.32 million square miles on Sept. 16, smashing old records for the critical climate indicator.
In this combination of photos, American physicist David Wineland (left) speaks at a news conference in Boulder, Colo., and French physicist Serge Haroche speaks to the media in Paris after they were named winners of the 2012 Nobel Prize in physics.
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Researchers say that springtime snow is melting in the Arctic even faster than Arctic ice. That means less sunlight is reflected off the surface. Bare land absorbs more solar energy, which can contribute to rising temperatures on Earth. Above, a musher races along the Iditarod in the Alaskan tundra in 2007.