“Hippo Chase”. As we approached the camp the Selinda Reserve of northern Botswana our boat passed by a hippo resting in the water. I turned around to look back at the boat's wake and saw the hippo charging after us! The hippo must've been tired from an all-nighter because he was angry. He rose way up out of the water three times trying to chase our boat! He was coming at us with such force that he created a wake of his own. Photo location: Selinda Reserve of northern Botswana. (Photo and caption by Curtis Simmons/National Geographic Photo Contest)

What would superheroes do if they had a part time job? Well… besides fighting crime, the powers of most superheroes aren’t exactly very useful. Sure, Flash would make a great delivery boy, delivering the freshest pizza in the world, while Thor might turn out to be a great smith (though judging by the way he handles his mallet, it is very unlikely), but in the end of the day, all these things are pretty useless. It sure is hard being a superhero when you have no villains to catch; especially if the only superpower that you have is lighting yourself on fire. Reducing you to a mere job of being used as fuel for cooking grilled chicken. Besides, it’s not exactly useful for catching villains either, if you don't plan on burning them alive… (Photo by Chow Hon Lam)

A street vendor spreads vermilion powder used for worship during the Tihar festival, also called Diwali in Kathmandu, Nepal, November 9, 2015. Hindus all over Nepal are celebrating the Tihar festival during which they worship cows, which are considered a maternal figure, and other animals. Also known as the festival of lights, devotees also worship the goddess of wealth Laxmi by illuminating and decorating their homes using garlands, oil lamps, candles and colourful light bulbs. (Photo by Navesh Chitrakar/Reuters)

A photographer has discovered a spectacular way of keeping warm during winter – using fire to heat up icy locations. Sam Scholes uses long-exposures to capture the movement of fire in front of ice-covered backdrops. After lighting steel wool his friend Scott Stringham swings the flaming object in order to make swirling patterns. The result of this technique – captured at Midway Ice Castles in Utah is a vibrant image with the warm light dancing across the cold scenes. (Photo by Sam Scholes/Caters News)

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)

We place too much value into something as elusive as time. This is the lesson that Arina Pozdnyak, the creator of Perpetual Calendar, is trying to teach us. Days fly by, and even months are mere speckles of sand in an hourglass of eternity. People do not realize that the time given to us by fate cannot be measured using months or even years. It is measured using emotions and impressions. If a person lives to be 150 years old without experiencing any emotions, he might as well have lived one day, for all it’s worth. On the other hand, a person who lived an exciting, fulfilling life, read countless books and cherished every moment that he had, is actually the one who lived a longer life, even if in reality his flame was snuffed out much too soon. (Photo by Arina Pozdnyak)

A small series by illustration Alex Solis remembering those things that used to rule the world.

A “creuseur”, or digger, a plastic lantern on his head, readies to enter a copper and cobalt mine in Kawama, Democratic Republic of Congo on June 8, 2016. Cobalt is used in the batteries for electric cars and mobile phones. Working conditions are dangerous, often with no safety equipment or structural support for the tunnels. The diggers say they are paid on average US$2-3/day. (Photo by Michael Robinson Chavez/The Washington Post)