An image from a simulation of two black holes merging. Courtesy of SXS Collaboration hide caption

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Facebook board member Marc Andreessen, a Silicon Valley venture capitalist who uses Twitter prolifically, has apologized for tweets suggesting he supported colonialism. Kimberly White/Getty hide caption

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The Philae lander, seen here heading to a comet's surface after leaving the Rosetta spacecraft in 2014, isn't expected to send any more signals, the European Space Agency says. ESA/Rosetta/MPS for OSIRIS Team hide caption

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Bottles for sale at Passage de la Fleur, a natural wine shop in Brooklyn, N.Y. For some, natural wines must be completely unadulterated — without the use of sugar, clarifiers or other additives common in modern winemaking. Other natural winemakers, however, will use a little sulfur dioxide or added yeast to correct problems, according to Stephen Meuse, a wine buyer in Massachusetts. Andrea Shea for NPR hide caption

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Bernie Sanders told supporters after winning the New Hampshire primary, "The American people bailed out Wall Street; now it's Wall Street's time to help the middle class." J. David Ake/AP hide caption

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Bernie Sanders and Hillary Clinton participate in the PBS NewsHour Democratic presidential candidate debate Thursday at the University of Wisconsin, Milwaukee. Win McNamee/Getty Images hide caption

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Medhi Salimian uses the words of Hafez — and the help of his bird, Sarah — to tell fortunes. Steve Inskeep/NPR hide caption

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People gathered during a candlelight procession to honor the memory of Giulio Regeni in his hometown of Fiumicello, Italy, on Sunday. Paolo Giovannini/AP hide caption

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Cliven Bundy stands along the road near his ranch after speaking with media in Bunkerville, Nev., on Jan. 27. His sons led the occupation of the Malheur National Wildlife Refuge in Oregon, and he was arrested Wednesday on charges stemming from a 2014 standoff with federal agents. John Locher/AP hide caption

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Russian Foreign Minister Sergey Lavrov (left) and Secretary of State John Kerry (second from left) attend the International Syria Support Group meeting in Munich, Germany, on Thursday along with members of the Syrian opposition and other officials. Michael Dalder/AP hide caption

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A reconstruction of a Neanderthal man (right) based on skull found at the La Ferrassie rock shelter in Dordogne Valley, France. He's face to face with a male Homo sapien. Philippe Plailly & Atelier Daynes/Science Source hide caption

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