The X-47B prototype on Tuesday flew off an aircraft carrier and into the history books. Today's achievement, the first-ever catapult launch of an unmanned aircraft from the flight deck of a carrier, promises to open up a new chapter in the annals of naval aviation. Photo: An X-47B pilot-less drone combat aircraft is launched for the first time off an aircraft carrier, the USS George H. W. Bush, in the Atlantic Ocean off the coast of Virginia, May 14, 2013. The U.S. Navy made aviation history on Tuesday by catapulting an unmanned jet off an aircraft carrier for the first time, testing a long-range, stealthy, bat-winged plane that represents a jump forward in drone technology. (Photo by Jason Reed/Reuters)

A figure of a skeleton is seen painted in a hallway of the house built underground by Manuel Barrantes in San Isidro de Perez Zeledon, Costa Rica, March 14, 2016. Barrantes started digging through red soil and volcanic rock on his farm 12 years ago to build his subterranean house, between 15 and 63 feet (4.57 and 19.2m) underground. The dwelling, which Barrantes says provides a peaceful and comfortable home for him and his family away from noise pollution and the effects of climate change, now covers about 2,000 square feet (185.8 square metres). (Photo by Juan Carlos Ulate/Reuters)

In this photo taken on Sunday, February 15, 2015 a girl runs away from a “Mamuxarro” during the carnival, in the small town of Unanu, northern Spain. In the northern Spanish ancient village of Unamu, people dress up as “Mamuxarro”, folkloric figures in white with a red sash and a metal mask to cover their faces as they pursue townsfolk with sticks. According to custom, their “victims” (usually young women) must kneel and kiss the mamuxarro’s knee after he makes the sign of the cross on their forehead. (Photo by Alvaro Barrientos/AP Photo)

Now celebrating its 40th year, Nikon Small World is widely regarded as the leading forum to recognize proficiency and photographic excellence of photography taken under the microscope. To select the winners, competition judges analyzed entries from all over the world covering subjects ranging from chemical compounds to up-close-and-personal looks at biological specimens. The 2014 winners will be revealed on October 30th. In 2014, the competition received over 1,200 entries from more than 79 countries around the world. (Photo by Dr. Igor Robert Siwanowicz/Nikon Small World 2014)

The phenomenon of the Hill of Crosses in northern Lithuania began when people started leaving crosses there hundreds of years ago – and continues to this day. These photos of a hill covered in crosses show the amazing sight it has become. Photo: In 1831 an unsuccessful uprising against the Russian czar left many rebels dead. Relatives of the dead rebels, with no bodies to bury, instead left crosses, according to the Daily Mail. (Photo by Richard Gardner/Rex USA)

“Rosslyn Chapel, properly named the Collegiate Chapel of St. Matthew, was founded on a small hill above Roslin Glen as a Roman Catholic collegiate church (with between four and six ordained canons and two boy choristers) in the mid-15th century. Rosslyn Chapel and the nearby Roslin Castle are located at the village of Roslin, Midlothian, Scotland”. – Wikipedia

Photo: The interior of Rosslyn Chapel on February 9, 2012 in Roslin, Scotland. Built between 1446 and 1484 it is a category A listed building, covered in ornate stonework and carvings of individual figures and scenes. People travel from all over the world to visit the chapel which many have described as an architectural wonder and a library in stone. Many theories, myths and legends associated with the Chapel have given it a unique sense of mystery and wonder. (Photo by Jeff J. Mitchell/Getty Images)

While communism, collectivism, worms, dry rot and casual looting failed to destroy the majestic wooden churches of Russia, it may be ordinary neglect that finally does them in. Dwindled now to several hundred remaining examples, these glories of vernacular architecture lie scattered amid the vastness of the world’s largest country. Just over a decade ago, Richard Davies, a British architectural photographer, struck out on a mission to record the fragile and poetic structures. Austerely beautiful and haunting, “Wooden Churches: Traveling in the Russian North” (White Sea Publishing; $132) is the result. Covering thousands of miles, Mr. Davies described how he and the writer Matilda Moreton tracked down the survivors from among the thousands of onion-domed structures built after Prince Vladimir converted to Christianity in 988.

A girl salutes to visitors before a show at the Mangyongdae Children's Palace in central Pyongyang, North Korea May 5, 2016. Pyongyang held a gala of song and dance performances by local school children on May 5 for visiting delegations of foreign journalists and tourists at the Mangyongdae Children's Palace. The event included orchestral, choir, and acrobatic performances, many of them with political undertones. The Seventh Worker's Party Congress commences on May 6, 2016. (Photo by Damir Sagolj/Reuters)