Boeing B-29 (#10) from the 24th Bomb Squadron, 6th Bomb Group after an emergency landing at Iwo Jima on April 24,1945. (Photo by U.S. Air Force)

After some days with temperatures below freezing point, I was out skating at some lakes at the outskirts of Oslo in Norway. After a while I noticed something on the ice. To my astonishment it was a dead frozen frog.

Gold medallist Rachelle Simpson of the U.S. celebrates after the women's 20m high dive competition during the Aquatics World Championships in Kazan, Russia August 4, 2015. (Photo by Hannibal Hanschke/Reuters)

A worker refreshes himself with a fan after loading a container with rice bags at an export plant in the central Chainat province in Thailand, December 16, 2015. (Photo by Jorge Silva/Reuters)

“After an afternoon of hiking and exploring the caves of Rhossili Bay, West Glamorgan, we caught the sun breaking through the clouds”. (Photo by Megan Warren-Davis/The Guardian)

A Hindu devotee displays his inked hand after taking part in the religious festival of Holi in Vrindavan, in the northern state of Uttar Pradesh, India, March 8, 2017. (Photo by Cathal McNaughton/Reuters)

An ultra-Orthodox Jewish bride takes part in the “mitzva tantz”, the custom in which relatives dance in front of the bride after her wedding ceremony, in Netanya, Israel, early March 16, 2016. (Photo by Baz Ratner/Reuters)

Hotel staff practice self-defence skills after a training session given by team member of Special Weapons and Tactics (SWAT) team, in Hangzhou, Zhejiang province, April 7, 2016. (Photo by Reuters/Stringer)