A 70-metre-long Noah's Ark replica constructed of steel and American cedar on March 31, 2005 in Schagen, Netherlands. (Photo by Michel Porro/Getty Images)

A robot is seen on Mount Etna, Italy on July 4, 2017. Mount Etna, in Sicily, is a test bed for the approximately three-foot high, four-wheeled machine ahead of a future mission to the moon. It is being conducted by the German Aerospace Centre, the agency which runs Germany's space programme. (Photo by Antonio Parrinello/Reuters)

Cardboard cut outs of the faces of three candidates for the Republican nomination for the 2016 US Presidential election (L-R) Ted Cruz, Donald Trump and Marco Rubio, are seen set up on urinals in a pub in London on March 1, 2016 as part of an informal poll for customers to log which they dislike the most. Part of the satirical television show The Last Leg, customers at the pub are able to choose which urinal to use and then log their poll on a list on the wall afterwards. (Photo by Justin Tallis/AFP Photo)

An Iraqi soldier stands guard as a pipeline burns in the background after an explosion 30 kilometers (20 miles) northeast of Tikrit, Iraq, Monday, February 11, 2008. (Photo by Bassem Daham/AP Photo)

These stunning pictures show a normally vicious tiger calmly swimming in a pool of algae, on Jule 9, 2014. The powerful cat takes a refreshing break by taking a dip in the bright green algae. But it looks like this big cat is scared of getting his head wet as he strains to keep it above the water. After splashing around for a bit the tiger gets out and tries to air-dry with specks of the vegetation dripping off his fur. The striking pictures were taken at Copenhagen zoo by snapper Soren Lundgren Neilson. (Photo by Soren Nielsen/Caters News)

Aurorae category runner-up: Lone Tree under a Scandinavian Aurora by Tom Archer (UK). The photographer decided to explore the area around the hotel on a very crisp -35C evening in Finnish Lapland. When he found this tree, he decided to wait for the misty conditions to change and could not believe his luck when the sky cleared and the aurora came out in the perfect spot. Archer spent about an hour photographing it before his camera started to lock up because of the harsh conditions, but by then he was happy to call it a night. (Photo by Tom Archer/2020 Astronomy Photographer of the Year)

Indonesian students wearing paper masks take part in the East Java Mask Parade in Surabaya, Indonesia, 13 December 2015. Thousands of people participate in the traditional parade to preserve the mask custom among the younger generation. (Photo by Fully Handoko/EPA)

A group of dancers pose for a photo before their performance at the Nueva Esperanza cemetery in the shantytown Villa Maria, in Lima, Peru, Tuesday, November 1, 2016, as part of the Day of the Dead festivities. The holiday honors the deceased and coincides with All Saints Day, and All Souls Day celebrated on Nov. 1 and 2. Dancing, drinking alcohol, and eating with the deceased are part of Day of the Dead celebrations. (Photo by Martin Mejia/AP Photo)