The moon shines through trees at a United Nations displacement camp at dusk on March 14, 2011 in Ras Jdir, Tunisia. (Photo by Dan Kitwood/Getty Images)

An internally displaced Afghan girl plays near their shelter at a refugee camp in Kabul January 13, 2015. (Photo by Omar Sobhani/Reuters)

A Palestinian youth practices his parkour skills at Shati refugee camp in Gaza City April 27, 2014. (Photo by Mohammed Salem/Reuters)

Members of the local Cossack community undergo military training at a boot camp set up by the Russkiye Vityazi (Russian Knights) military patriotic club in the village of Sengileyevskoye, south of Stavropol, March 22, 2015. A group of cossacks from the village of Kazanskaya, who are planning a professional career at the military intelligence service, has arrived at a camp for training under the leadership of professional instructors. (Photo by Eduard Korniyenko/Reuters)

Northern lights (Aurora borealis) glow brightly over an Inupiaq fish camp along the arctic coast in North Slope, Alaska. (Photo by Steven Kazlowski/Barcroft Media)

Refugees disembark and make their way to a camp at a hotel touted as the world's most northerly ski resort in Riksgransen, Sweden, December 15, 2015. (Photo by Ints Kalnins/Reuters)

An Ethiopian Orthodox monk prays within a rock hewn church ahead of Ethiopian Christmas in Lalibela, January 6, 2017, which is celebrated on January 7. (Photo by Tiksa Negeri/Reuters)

A migrant tries to restrain her tent from strong winds in a makeshift camp for refugees and migrants at the Greek-Macedonian border near the village of Idomeni, Greece, March 24, 2016. (Photo by Alexandros Avramidis/Reuters)