A protester throws a stone towards a burning police bus in front of him, during clashes with police, in central Kiev, Ukraine, Sunday, January 19, 2014. Hundreds of protesters on Sunday clashed with riot police in the center of the Ukrainian capital, after the passage of harsh anti-protest legislation last week seen as part of attempts to quash anti-government demonstrations. The violent scenes further escalated this ex-Soviet republic's political crisis and showed a rift among opposition leaders, one of whom fought bravely to stop the violence, while others condemned the events from afar. (Photo by Evgeny Feldman/AP Photo)

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)

Gers, traditional Mongolian tents, are seen on a hill in an area known as a ger district in Ulan Bator June 26, 2013. Approximately 60 percent of the population of Ulan Bator live in settlements known as ger districts and in many cases residents have limited access to basic services such as water and sanitation. According to a 2010 National Population Center census, every year between thirty and forty thousand people migrate from the countryside to the capital Ulan Bator. Ger districts in the city have been expanding rapidly in recent years. Mongolia is the world's least densely populated country, with 2.8 million people spread across an area around three times the size of France. (Photo by Carlos Barria/Reuters)

Kyaiktiyo Pagoda, also known as Golden Rock is a well-known Buddhist pilgrimage site in Mon State, Burma. It is a small pagoda (7.3 metres (24 ft)) built on the top of a granite boulder covered with gold leaves pasted on by devotees. According to legend, the Golden Rock itself is precariously perched on a strand of the Buddha's hair. The balancing rock seems to defy gravity, as it perpetually appears to be on the verge of rolling down the hill. The rock and the pagoda are at the top of Mt. Kyaiktiyo. It is the third most important Buddhist pilgrimage site in Burma after the Shwedagon Pagoda and the Mahamuni Pagoda. A glimpse of the "gravity defying" Golden Rock is believed to be enough of an inspiration for any person to turn to Buddhism.

A rat being trained by the Cambodian Mine Action Centre (CMAC) is pictured on an inactive landmine field in Siem Reap province July 9, 2015. Gambian pouched rats were deployed to Cambodia from Tanzania in April by a Belgian non-profit organization, APOPO, to help clear mines. They've been trained since they were 4 weeks old. Cambodia is still littered with landmines after emerging from decades of civil war, including the 1970s Khmer Rough “Killing Fields” genocide, leaving it with one of the world's highest disability rates. APOPO has used the rodents for mine-clearing projects in several countries, including Angola, Mozambique, Thailand, Laos, and Vietnam. (Photo by Samrang Pring/Reuters)

Farmers use tractors and burn tires, hay and manure as they block the highway between Morlaix and Brest during a demonstration against the market prices of their product, on July 22, 2015 in Morlaix, western of France. French farmers protesting over falling food prices threatened to step up blockades of cities, roads and tourist sites, as the government prepared to unveil emergency aid for them. Farmers have dumped manure in cities, blocked access roads and motorways and hindered tourists from reaching Mont St-Michel in northern France, one of France's most visited sites. (Photo by Fred Tanneau/AFP Photo)

“David Doubilet (born 28 November 1946) is a well known underwater photographer known primarily for his work published in National Geographic Magazine. He was born in New York and started taking photos underwater at the young age of 12. He started with a Brownie Hawkeye in a rubber anesthesiologist's bag to keep the water out of the camera. During his summer holidays, he spent his time along the New Jersey coast. He later worked as a diver and photographer for the Sandy Hook Marine Laboratories in New Jersey. He also spent much time in the Caribbean. While a dive instructor in the Bahamas he found his motivation to capture the beauty of the sea and everything in it”. – Wikipedia. (Photo by David Doubilet/National Geographic)