Meerkats are weighed and measured during the ZSL London Zoo 's annual weigh-in on August 22, 2012 in London, England. The height and mass of every animal in the zoo, of which there are over 16,000, needs to be recorded. The measurements are collated in the Zoological Information Management System, from which zoologists can use the data to compare information on thousands of endangered species. (Photo by Oli Scarff)

The second and final qualification motor (QM-2) test for the Space Launch System's booster, June 28, 2016, at Orbital ATK Propulsion Systems test facilities in Promontory, Utah. During the Space Launch System flight the boosters will provide more than 75 percent of the thrust needed to escape the gravitational pull of the Earth, the first step on NASA's Journey to Mars. (Photo by Bill Ingalls/NASA)

Joseph Szabo was a frustrated high-school teacher in need of inspiration – so he started photographing his students, and captured all the angst and excitement of being caught between childhood and adulthood. Here: “Priscilla”, 1969. (Photo by Joseph Szabo/Courtesy of Michael Hoppen Gallery/The Guardian)

Talented French artist, Pierre Beteille, is skillful in manipulation of portraits (specially his own self portraits) using Photoshop. This is how he describes himself: “I am not a photographer or an artist, I just make images… I shoot very average or even bad photos that I try to improve thanks to Photoshop”…

Photo: “En attendant d'avoir des balles”...., 2007 (Photo by Pierre Beteille)

“I started photography in June 2009. At the time, I was searching for a way to express both the rigorous scientist and the creative artist in me. There are few hobbies that let these two approaches work together, so I really was enthusiastic about it: I am now spending all my free time studying various techniques, contemplating others' fantastic work, and of course, making pictures”. – Christophe Kiciak. Photo: “The Hero”. (Photo by Christophe Kiciak)

«After Presents», 1996. Siri Kaur: “I was 14 when Simran was born in 1990. We have different mothers, so we grew up separately and I made pictures with her whenever I saw her. The work of Sally Mann and Nan Goldin gave me permission to see my family as a valid art subject. This image shows the aftermath of Christmas morning. Simran is unselfconsciously lounging on the floor, melding into her beloved dog”. (Photo by Siri Kaur)