Spacewalker Mark Vande Hei took his own photograph during the first spacewalk of 2018, on January 23, 2018. These sky-high pictures are better known as “space-selfies”. (Photo by Mark Vande Hei/NASA)

Cooperation is key to success. This motto was used by the Government of Denmark when they decided to create a project that bore the name of UN City. This compound was designed to house all nine Copenhagen based UN agencies under a single roof. This embodies the core idea of the United Nations, since this project allows for better efficiency and practicality thanks to joint effort. The first plans for the UN City were hatched in 2002. After 11 years, in 2013 the first stage of the project was finally finished. Presently, Campus 1 of UN City accommodates 1,300 staff member, while Campus 2 is going to become the largest humanitarian warehouse in the whole world.

Divers swim beside millions of silverside fish at Devil's Grotto, Cayman Islands. Swimming in unison, millions of silverside fish dwarf the divers. The fish create waves of silver light as they move around the grottos that lie beneath the surface of the Caribbean Sea. These amazing photographs were captured by Belgian photographer Ellen Cuylaerts, 44, on a diving trip to the Devil's Grotto, Cayman Islands. (Photo by Ellen Cuylaerts/This is Guavo Media)

The Invasion. A quiet street in Macau. Modernization around is quickly changing the city, as documented by Paul Tsui. (Photo by Paul Tsui/National Geographic Travel Photographer of the Year Contest)

Eight year-old Maya Mohammad Ali Merhi walks using prosthetic legs made by her father from tin cans in a camp for displaced people, in the northern Syrian province of Idlib on June 20, 2018. Maya and her father were both born without lower limbs. Unable to afford real prosthetic limbs, her father made her a pair out of tin cans filled with cotton and scrap pieces of cloth. Maya's family had to leave their home in the Aleppo province to flee battles. (Photo by Aaref Watad/AFP Photo)

In this handout image supplied by Qatar 2022 The Al-Rayyan stadium is pictured in this artists impression as Qatar 2022 World Cup bid unveils it's stadiums on September 16, 2010 in Doha, Qatar. It has been designed to include a “media facade” that includes a membrane that acts as a screen for projections; news, commercials, sports updates and current tournament information and matches. (Photo by Qatar 2022 via Getty Images)

“Scott Linstead is an internationally published, freelance wildlife photographer/writer. His clients include Natural History Magazine, Hewlett Packard, Ranger Rick Magazine and a number of wildlife publications in North America and Europe. Scott's column on the techniques of bird photography appears in every issue of Outdoor Photography Canada”.

Photo: A veiled chameleon extends its tongue to catch a cricket. Canadian wildlife photographer Scott Linstead, formerly an aerospace engineer and high school teacher, uses a device called Phototrap “to not only photograph the elusive, but also the unimaginably quick”. (Photo by Scott Linstead)