The AMECA robot from the manufacturer Engineered Arts is in the Deutsches Museum Nuremberg (Future Museum), Bavaria on May 3, 2022. AMECA is a humanoid robot that will be presented to the general public for the first time in Europe as part of the Blue Night on May 7, 2022 in Nuremberg. (Photo by Daniel Karmann/dpa/Alamy Live News)

These are the dunes of the Namib Desert, taken by Korea's Kompstat-2 satellite. The blue and white area is the dried riverbed of the Tsauchab river. (Photo by The European Space Agency)

Ling Pham attends the L'Oreal Paris Blue Obsession Party at the annual 69th Cannes Film Festival at Hotel Martinez on May 18, 2016 in Cannes, France. (Photo by Pascal Le Segretain/Getty Images)

A reflection on waste liquid shows a tourist walking near the Blue mosque at the Sultanahmet Square on the first day of the Muslim fasting month of Ramadan in Istanbul on April 13, 2021. (Photo by Ozan Kose/AFP Photo)

A blue-tailed bee-eater chases down its prey along the banks of the Kaveri River on the outskirts of the city of Mysore, India in the last decade of June 2025. (Photo by Nitin Jain/Solent News)

These photographs appear to show a spectacular underwater world making it ideal for scuba divers – in central Europe. Twelve metres of water covers trees, footpaths, benches and bridges that are usually accessible throughout the year. Visitors to the Green Lake in Tragoess, Austria, that is normally only one metre deep, can leisurely stroll around the picturesque lagoon. Photo: A diver crossing a bridge in the flood water. (Photo by Solnet/The Grosby Group)

Jellyfish Lake (Palauan: Ongeim'l Tketau, “Fifth Lake”) is a marine lake located on Eil Malk island in Palau. Eil Malk is part of the Rock Islands, a group of small, rocky, mostly uninhabited islands in Palau's Southern Lagoon, between Koror and Peleliu. There are about 70 other marine lakes located throughout the Rock Islands. Jellyfish Lake is one of Palau's most famous dive (snorkeling only) sites. It is notable for the millions of golden jellyfish which migrate horizontally across the lake daily.

Marianne Brauns jumping a breakwater on the beach, wearing a structured blue swimsuit with white trim. (Photo by Carl Sutton/Hulton Archive/Getty Images). Circa 1950