This is the moment a diver appears to shake hands with a giant 52ft whale. The divers were just metres away when one humpback whale – which weighs 36,000kg – extends its giant flipper in a peaceful manner. (Photo by Masa Ushioda/SeaPics/Solent News & Photo Agency)

Dhofar Region, Oman. Much of Oman is desert, but the Arabian Sea coast in the Dhofar region represents a startling difference in climate. This coastal region catches the monsoon rains, or khareef, during the summer months. Drenching rains fall primarily on the mountainous ridge that separates the lush, fertile areas along the coast from the arid interior, recharging streams, waterfalls and springs that provide plentiful water supplies in the fertile lowlands for the remainder of the year. Image taken by Landsat 5 on April 2, 2005. (Photo by USGS/NASA)

A Soyuz MS-11 rocket carrying Russian, American and Canadian astronauts takes off from the Baikonur Cosmodrome on December 3, 2018 before reached orbit later, the first manned mission since a failed launch in October. (Photo by Kirill Kudryavtsev/AFP Photo)

Group of blow-up dolls and women. (Photo by Zomi/Getty Images)

Elena Chernyshova's vision of Norilsk, Russia, the northernmost city in the world, is a series of surprises by which she extracts otherworldly beauty from ugly realities. Here: 2013. A woman is visible through a narrow passageway between two buildings. Norilsk's urban spaces were designed to shorten distances around large developments and give residents maximum protection from arctic winds. (Photo by Elena Chernyshova)

Brush your teeth and get cleaned up for the week ahead! These animals answered the call of good dental hygiene. Here: Hamster holds toothbrush. (Photo by Neo Vision/Getty Images/Amana Images RM)

Young man making the O.K. sign. (Photo by George Marks/Retrofile/Getty Images). Circa 1950s