A zookeeper feeds a hippopotamus with a watermelon in its enclosure in Belgrade's zoo, Serbia, July 20, 2015. Temperatures in Serbia have risen up to 40 degrees Celsius (104 degrees Fahrenheit), according to official meteorological data. (Photo by Marko Djurica/Reuters)

Flash, a golden retriever, plays with a toy following a press event for the American Kennel Club to reveal the nations most popular dog breeds in the Manhattan borough of New York, February 22, 2016. (Photo by Carlo Allegri/Reuters)

Apple CEO Tim Cook discusses the new iPhone 6 and iPhone 6 plus on Tuesday, September 9, 2014, in Cupertino, Calif. The iPhone 6 will have a screen measuring 4.7 inches, while the iPhone 6 Plus will be 5.5 inches. (Photo by Marcio Jose Sanchez/AP Photo)

These incredible pictures look like a bird's-eye view of a faraway alien planet – but they're actually hot springs. The amazing snaps are up-close shots of Iceland's hot springs, and the point-blank pictures produce a breathtaking array of colors and effects. Here: The amazing snaps are up-close shots of Icelandic hot springs. (Photo by Johann Vilhjalmsson/Caters News)

Hot air balloons in flight over Melbourne, Australia on January 24, 2022. (Photo by Rex Features/Shutterstock)

Dozens of hot air balloons fill the sky on the second day of the 2024 International Balloon Festival (FIG) in Leon, Mexico, 16 November 2024. (Photo by Luis Ramirez/EPA)

A hot-air balloon flies over Metropolitan Park during the International Hot-Air Balloon Festival in Leon, state of Guanajuato, Mexico, on November 16, 2024. (Photo by Henry Romero/Reuters)

A woman wearing a bikini stands next to fuel pumps as she waits to top up fuel at a petrol station in Kiev, Ukraine, September 26, 2015. One of the largest networks of petrol stations in Ukraine organized a campaign in which anyone who showed up in swimwear at a particular gas station during specified hours would receive free gasoline, according to representatives of the company. (Photo by Valentyn Ogirenko/Reuters)