An artist's depiction of NASA's Spirit rover on the surface of Mars. Spirit became unresponsive in March 2010. NASA announced it had ended attempts to communicate with the rover on May 24, 2011. NASA hide caption

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Lexi (middle) with her two younger brothers Jorge (left) and Keegan. Before Lexi and her brother's were adopted, Lexi was their prime caretaker. "I fed them when they were very, very hungry," Lexi says. Courtesy of Rebecca hide caption

itoggle caption Courtesy of Rebecca

A wall of Hesco baskets protects the Riverside Medical Center in Vidalia, La., from Mississippi River floodwaters. Gerald Herbert/AP hide caption

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A satellite image shows a field of what may be buried pyramid sites in Egypt. Courtesy of DigitalGlobe Images hide caption

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Robert Dixon Sr. holds a photograph of his son, Robert Dixon Jr. (far right), his son's mentor Bob Stuart, and himself (far left). Lianne Milton for NPR hide caption

itoggle caption Lianne Milton for NPR

President Dwight Eisenhower touches the head of Dzimbo, a 440-pound elephant, on Oct. 12, 1959. The French Community of African Republics sent Dzimbo to Washington as a gift for the president. Byron Rollins/AP hide caption

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Former Minnesota Gov. Tim Pawlenty announces in Des Moines, Iowa, that he's running for president on Monday. Steve Pope/Getty Images hide caption

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President Obama and first lady Michelle Obama sample Guinness at a pub in the village of Moneygall, Ireland. Obama's great-great-great grandfather Falmouth Kearney was a shoemaker in the town until 1850, when he left for the United States. Jewel Samad/AFP/Getty Images hide caption

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President Obama arrives to speak at the American Israel Public Affairs Committee convention in Washington, D.C., on Sunday. Obama tried to defuse the controversy that erupted last week when he argued that Palestinian-Israeli peace talks should begin with Israel's 1967 borders, with mutually agreed upon land swaps. J. Scott Applewhite/AP hide caption

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Learning juicy details about someone can change the way you see them — literally, according to a new study. August Darwell/Getty Images hide caption

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Two officers with the Raleigh County Sheriff's Office stand guard in front of the Upper Big Branch coal mine several days after the April 5, 2010, explosion that killed 29 workers in Montcoal, W.Va. Mark Wilson/Getty Images hide caption

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Republican presidential candidate Newt Gingrich has acknowledged having an extramarital affair with Callista (above), then a congressional aide and now his third wife, while he was married to his second wife. Mike Stewart/AP hide caption

itoggle caption Mike Stewart/AP

San Diego resident Brennan Savage photographs his son, Liam, posing with the Madonna-surfing mosaic on Encinitas Boulevard's railroad bridge support. Charlie Neuman/The San Diego Union-Tribune via ZUMA Press hide caption

itoggle caption Charlie Neuman/The San Diego Union-Tribune via ZUMA Press