This aerial photo taken on December 28, 2018 shows commercial and residential buildings in Hong Kong. (Photo by Dale De La Rey/AFP Photo)

Castro's soldiers at Playa de Giron, Cuba, after thwarting the ill-fated US backed 'Bay of Pigs' invasion. (Photo by Graf/Getty Images). April, 1961

Members of the Al-Baraa bin Malek batallion, part of the Free Syria Army's Al-Fatah brigade, duck to the ground as they pull a man (R) who was shot by a sniper twice in the Bustan al-Basha district of the northern city of Aleppo on October 20, 2012. (Photo by Javier Manzano/AFP Photo)

A Mai-Mai rebel soldier shows off his guns at a checkpoint near the Mugunga refugee camp in Zaire; 1996. (Photo by Carol Guzy/The Washington Post)

“The scientists behind NASA's $2.5 billion Curiosity rover mission on Mars on Tuesday explained the nature of a tiny, gleaming "flower" embedded in Red Planet rock, and revealed where they'll be using the SUV-sized robot's drill for the first time”. – Alan Boyle via NBCNews.com

Photo: Scientists say that a “Martian flower”, seen here in an image from the Curiosity rover's Mars Hand Lens Imager, is a 2-millimeter-wide grain or pebble that's embedded in the surrounding rock. Another, darker-colored mineral grain can be seen above and to the left. (Photo by NASA)

In this photograph taken on July 10, 2012, a Pakistani worker pulls on a wire he will connect to a thick chain that will in turn be used to peel away a slab of the outer structure of a beached vessel in one of the 127 ship-breaking plots in Geddani, some 40Kms west of Karachi. (Photo by Roberto Schmidt/AFP Photo)

Alice Ross views a gold crown which was presented to Queen Victoria, part of the Royal Collection on display at the Queens Gallery on March 13, 2012 in Edinburgh, Scotland. The exhibition, which marks Her Majesty The Queen's Diamond Jubilee, reflects the tastes of monarchs and other members of the royal family who have shaped one of the world's great art collections. (Photo by Jeff J. Mitchell/Getty Images)