NASA says it could be another 20 years before humans touch down on Mars, but in a sense, the Mars Society has been exploring the red planet for more than a decade – in Utah. Photo: Csilla Orgel, a geologist of Crew 125 EuroMoonMars B mission, makes her way back to the Mars Desert Research Station (MDRS) in the Utah desert March 3, 2013. The MDRS aims to investigate the feasibility of a human exploration of Mars and uses the Utah desert's Mars-like terrain to simulate working conditions on the red planet. Scientists, students and enthusiasts work together developing field tactics and studying the terrain. All outdoor exploration is done wearing simulated spacesuits and carrying air supply packs and crews live together in a small communication base with limited amounts of electricity, food, oxygen and water. Everything needed to survive must be produced, fixed and replaced on site. (Photo by Jim Urquhart/Reuters)

A model stands next to a BMW X6 AC Schnitzer car at Auto China 2012 in Beijing in this April 24, 2012 file photo. Amid the razzmatazz, music and crowds at the Shanghai autoshow on Monday, hundreds of attractive young women, and men, mingled among the stands and company booths, introducing the newest sedans and handing out pamphlets. For years, models have been a staple at China's big autoshows – as much of a draw as the latest car models themselves. 2015 is different – the organisers have banned models from the Shanghai show. (Photo by Jason Lee/Reuters)

Employees stand near an airframe for the second Antonov-225 Mriya plane at Antonov aircraft plant in Kiev, Ukraine, September 7, 2016. Ukraine hopes to attract $500 million of investment from China to complete an updated version of the world's biggest aircraft, the Antonov-225 Mriya, the president of manufacturer Antonov said on Wednesday. (Photo by Valentyn Ogirenko/Reuters)

“Nomascus is the second most speciose genus of gibbons (family Hylobatidae). Originally this genus was a subgenus of Hylobates, and all individuals were considered one species, Hylobates concolor. Species within Nomascus are characterized by 52 chromosomes. Some species are all black, some light with a distinct black tuft of crown fur, and some by distinct, light-colored cheek patches. Nomascus is found from southern China (Yunnan) to southern Vietnam, and also on Hainan Island. One of the genus' species, Nomascus nasutus, has been deemed “the most critically endangered ape species in the world”. All of the species in this genus are endangered or critically endangered”. – Wikipedia

Photo: A newborn White-Cheeked Gibbon clings to its mother in the Nanning Zoo on April 12, 2004 in Nanning, Guangxi province, China. The White-Cheeked Gibbon's natural habitat is Southern China as well as Vietnam and Laos. They are classified as highly endangered and are on the brink of extinction due to poaching and reduction of natural rainforests. (Photo by Getty Images)

“The Red River Hog (Potamochoerus porcus), also known as the Bush Pig (but not to be confused with P. larvatus, common name “Bushpig”), is a wild member of the pig family living in Africa, with most of its distribution in the Guinean and Congolian forests. It is rarely seen away from rainforests, and generally prefers areas near rivers or swamps.

Red River Hogs eat grass, berries, roots, insects, molluscs, small vertebrates and carrion. They are capable of causing damage to plantations. Red River Hogs typically live in herds of 6-20 members led by a dominant boar. Sows rear 3-6 piglets at a time.”

Photo: Two 17 day old red river hoglet twins forage for food next to their mother Bahiti at London Zoo on August 23, 2007 in London, England. Red River hoglets inhabit the forests and swamps of West and Central Africa. The recent additions to the London Zoo pig pen have been eagerly awaited by zoo keepers. (Photo by Chris Jackson/Getty Images)

A Tengger tribesman prays at Mount Bromo during the annual Kasada ceremony in East Java on August 12, 2014. The Kasada ceremony is a festival held every 14th day of the Kasada month in the traditional Hindu lunar calender to honour Sang Hyang Widhi (God Almighty) and is based on the legend of Roro Anteng and Joko Seger from the Majapahit Kingdom, from which their Tengger tribe name originates. Hundreds of worshippers from the Tengger tribe offer food and livestock as a symbolic sacrifice which they throw into the crater for the blessings of safety and prosperity to their familyies and community. (Photo by Juni Kriswanto/AFP Photo)

In 2002 photographer Corey Arnold left behind a poor economy in San Francisco and headed up to Alaska to try his luck at his longtime passion of fishing. Arnold, who had worked summers during college on a salmon boat in Alaska, signed onto the f/v Rollo, a crabbing boat that fishes in the dangerous Bering Sea. While working long, strenuous hours on the Rollo, Arnold often stole away with the captain’s permission to grab his camera and photograph the crew and the ship. Arnold eventually put together “Fish Work: Bering Sea”, a documentation of his seven adventurous and dicey crab seasons aboard the Rollo. (Photo by Corey Arnold)

Ethnic Uyghur tourists guides wait to perform in a show for Chinese tourists on June 29, 2017 in the old town of Kashgar, in the far western Xinjiang province, China. Kashgar has long been considered the cultural heart of Xinjiang for the province's nearly 10 million Muslim Uyghurs. (Photo by Kevin Frayer/Getty Images)