Migrants scramble aboard a train at the station in Beli Manastir, Croatia September 18, 2015. Migrant numbers in Europe will build up in coming days and their flows may fragment further into new routes, the U.N. refugee agency said on Friday, urging the European Union to grasp a last chance to resolve the refugee crisis next week. (Photo by Laszlo Balogh/Reuters)

A man washes his horse as a woman bathes her son at concrete water pens under a flyover in a slum area in Kolkata, India October 21, 2016. (Photo by Rupak De Chowdhuri/Reuters)

Nursing and care personnel lay on the floor in the ICU unit, during a demonstration on International Nursing and Care day, at the Mont Legia Hospital in Liege, Belgium, Wednesday, May 12, 2021. Hospital personnel around Belgium took part in various actions around the country on Wednesday to highlight the work they do and demand better recognition. (Photo by Valentin Bianchi/AP Photo)

Night lovers; Hormozgan province, Iran. “In this picture, you can see the Milky Way rising on a fascinating spring night on the Persian Gulf coast. The stunning cliffs of this area make every viewer imagine and even talk to them! The light pollution from a faraway city was quite strong, so it was a challenging post-processing process. I’m a nightscaper who tries to achieve an artistic look in my images, and in this image, I tried to convey and capture the magic of this location”. (Photo by Mohammad Hayati/Milky Way Photographer of the Year)

Bonbibi, Treehouse Point, Fall City, WA. The Bonbibi is balanced on two steel yokes. The yokes spread out the load and allow for tree growth and movement in the wind. A small deck hangs from the beams below and uses the treehouse itself to shelter guests. (Photo by Pete Nelson)

Green Bay Packers' Johnathan Calvin rides a bike to NFL football training camp on July 27, 2017, in Green Bay, Wis. (Photo by Morry Gash/AP Photo)

A handout picture provided by Solar Impulse on 18 March 2015 shows the Swiss solar-powered plane Solar Impulse 2, HB-SIB, taking off with Swiss explorer Andre Borshberg on board for the third leg Ahmedabad to Varanasi, of the Round-The-World, in Ahmedabad, India, 18 March 2015. Swiss explorers Bertrand Piccard and Andre Borschberg attempt to circumnavigate the world flying with an aircraft, with a 72 metres wingspan, powered only by solar energy without a drop of fuel. (Photo by EPA/Solar Impulse)

A group of youngsters dressed as ghouls and zombies for Halloween parade in downtown Lisbon, Portugal, Friday, October 31, 2014. (Photo by Francisco Seco/AP Photo)