The NASA Extreme Environment Mission Operations (NEEMO) 21 mission began on July 21 as an international crew of aquanauts splashed down to the undersea Aquarius Reef Base, located 62 feet below the surface of the Atlantic Ocean in the Florida Keys National Marine Sanctuary. The NEEMO 21 crew will perform research both inside and outside the habitat during a 16-day simulated space mission. During simulated spacewalks carried out underwater, they will evaluate tools and mission operation techniques that could be used in future space missions, including journeys to Mars. (Photo by Karl Shreeves/NASA)

A visitor walks past an installation artwork entitled “Confuciuse” which combines the word “Confucius” and “confuse” in the contemporary art exhibition at “Fun and Art” Festival on December 13, 2008 in Xian of Shaanxi Province, China. (Photo by China Photos/Getty Images)

“Wombats are Australian marsupials; they are short-legged, muscular quadrupeds, approximately 1 metre (39 in) in length with a short, stubby tail. They are adaptable in their habitat tolerances, and are found in forested, mountainous, and heathland areas of south-eastern Australia, including Tasmania, as well as an isolated patch of about 300 ha in Epping Forest National Park in central Queensland”. – Wikipedia

Photo: “Abdul”, a baby Common Wombat, is one of the marsupials on show during the spring baby boom at Taronga Zoo September 1, 2005 in Sydney, Australia. “Abdul” was orphaned when his mother was killed by a car. (Photo by Mark Nolan/Getty Images)

“Alan Alexander “A. A.” Milne (18 January 1882 – 31 January 1956) was an English author. Milne is most famous for his two Pooh books about a boy named Christopher Robin after his son, and various characters inspired by his son's stuffed animals, most notably the bear named Winnie-the-Pooh”. – Wikipedia

Photo: A rare American first edition of a Winnie-the-Pooh book signed by the author A.A. Milne and illustrator E. H. Shephard is displayed with Pooh characters form a 1930's game at a press preview at Sotheby's Auctioneers on December 15, 2008 in London. (Photo by Peter Macdiarmid/Getty Images)

A tourist stands on the shore of a private beach in Naama Bay, Sharm el-Sheikh, south Sinai, Egypt, Sunday, November 8, 2015. Britain's foreign secretary says airport security in many cities will need to be overhauled if it is confirmed the Russian plane crash in the Sinai was caused by a bomb planted by the Islamic State group or someone inspired by the militants. (Photo by Vinciane Jacquet/AP Photo)

Police react to a suspicious vehicle near La Carillon restaurant following a series of deadly attacks in Paris, November 15, 2015. Thousands of French troops deployed around Paris on Sunday and tourist sites stood shuttered in one of the most visited cities on Earth while investigators questioned the relatives of a suspected suicide bomber involved in the country's deadliest violence since World War II. (Photo by Pascal Rossignol/Reuters)

Vendors sell clothes on the roadside at a second-hand street side clothing market in Mumbai January 28, 2015. The market is open daily for three hours and hundreds of vendors gather to barter or sell used clothing. (Photo by Danish Siddiqui/Reuters)

A young boy scoops water from a hand-dug well in the dry riverbed near Matinyani, in the semi-arid Kitui County in southeastern Kenya, 22 March 2015, the World Water Day. Residents of Kitui County and other arid and semi-arid areas of the country have been hard-hit by extremely poor rainfall this year while the government said in previous month that some 1.6 million people countrywide are facing acute starvation due to the drought and will need relief food over the next six months. Residents of Matinyani say they haven't seen a drop of rain in nearly four months. Thousands of Kenyans in rural areas walk tens of kilometers just to fetch water to drink and to be used in their homes. According to an estimate by UNESCO (United Nations Educational, Scientific and Cultural Organization), 17 million people lack access to safe water in Kenya, where the drought is a perennial problem. (Photo by Dai Kurokawa/EPA)