Chinese paramilitary guards monitoring passengers as they head to their train to travel to their hometowns for the “Spring Festival” or Lunar New Year at Nantong Railway Station in Jiangsu province, near Shanghai Travellers taking part in the world' s largest annual human migration must be home by January 27 to usher in the new year on January 28. (Photo by AFP Photo/Stringer)

This image obtained January 31, 2017 from the US Geological Survey's Hawaiian Volcano Observatory showing a lava stream, pouring out of the lava tube on the sea cliff at the Kamokuna ocean entry from the Kilauea Volcano on January 29. (Photo by AFP Photo/USGS)

Spanish director Pedro Almodovar and actress Penelope Cruz chat before the start of the Spanish Film Academy's Goya Awards ceremony in Madrid, Spain, February 4, 2017. (Photo by Paul Hanna/Reuters)

An injured Iraqi Emergency Response Division (ERD) soldier hit by a mortar is held by another officer as they wait for medics to arrive at the Islamic State occupied Mosul Airport in west Mosul, part of the offensive to retake the city some two years after it fell to the hardline jihadist group, February 23, 2017. Iraqi forces encountered stiff resistance with improvised explosives, heavy mortar fire and snipers hampering their advance before they successfully took the airport. (Photo by Martyn Aim/Getty Images)

Iraqi women cry over their brother's body, who was killed by a mortar shell fired by Islamic State (IS) group jihadists on civilians who were gathered to receive aid, in Al-Risala neighbourhood on March 22, 2017, as an ongoing offensive by Iraqi forces to retake the city from the group continues. Iraqi forces launched a major operation to recapture west Mosul – the most-populated urban area still held by IS – on February 19, and have retaken a series of neighbourhoods from the jihadists. (Photo by Ahmad Al-Rubaye/AFP Photo)

Fans are seen at the 143rd Kentucky Derby on May 6, 2017 in Louisville, Kentucky. (Photo by Michael Hickey/Getty Images)

A girl lights a candle as she marks the anniversary of 2015 Nepal earthquake, at Boudhanath stupa in Kathmandu, Nepal April 25, 2017. (Photo by Navesh Chitrakar/Reuters)

The Breitling DC-3, HB-IRJ, plane fly escorted by Italian Air Force's aerobatic demonstration team, the Frecce Tricolori, during the last stage of its world tour two days ahead of the International Sion Air Show, in Sion, Switzerland, 13 September 2017. From March to September 2017, the Breitling DC-3 from 1940 has done a grand world tour in several stages, over 28 countries and flies 50000km, an amazing accomplishment for this legendary plane that will be celebrating its 77th birthday. (Photo by Christian Merz/EPA/EFE)