Janet Collins was€” the first prima ballerina to perform at the Metropolitan Opera. Ed Palumbo/Library of Congress hide caption

itoggle caption Ed Palumbo/Library of Congress

Mayor of Leicester Peter Soulsby near a screen displaying a statue of King Richard III on Friday, after a decision to permit the monarch to be buried at Leicester Cathedral in central England. Darren Staples/Reuters/Landov hide caption

itoggle caption Darren Staples/Reuters/Landov

A 2011 photo shows a replica of Christopher Columbus' flagship, the Santa Maria, off the Portuguese island of Madeira. The location of the Santa Maria has been a mystery; an explorer says he might have found it. Eric Risberg/AP hide caption

itoggle caption Eric Risberg/AP

Vietnam veterans Melvin Morris (center), Jose Rodela (obscured) and Santiago J. Erevia (left) received the Medal of Honor from President Obama at the White House on Thursday. Win McNamee/Getty Images hide caption

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Abraham Lincoln, the 16th president, used to cook alongside his wife. Brady/Getty Images hide caption

itoggle caption Brady/Getty Images

Fon appliqué workers in 1971, Abomey, Republic of Benin. Eliot Elisofon/National Museum of African Art hide caption

itoggle caption Eliot Elisofon/National Museum of African Art

Tobacco companies incorporated doctors in their ads, such as this 1930 Lucky Strike campaign, to convince the public that smoking wasn't harmful. Stanford University hide caption

itoggle caption Stanford University

The Cathedral Spires in the Black Hills of South Dakota are just one of innumerable formations across the planet that speak to the Earth's ancient history. K. Scott Jackson/Ohio Water Science Center/USGS hide caption

itoggle caption K. Scott Jackson/Ohio Water Science Center/USGS

Part of the ALMA array on the Chajnantor plateau of Chile points skyward to the Milky Way, our own galaxy. The center of our galaxy is visible as a yellowish bulge crossed by dark lanes, which are themselves huge clouds of interstellar dust. José Francisco Salgado/ESO hide caption

itoggle caption José Francisco Salgado/ESO

President Abraham Lincoln's Gettysburg Address as inscribed on the stone at the Lincoln Memorial. Pat Benic/UPI/Landov hide caption

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