The NASA Extreme Environment Mission Operations (NEEMO) 21 mission began on July 21 as an international crew of aquanauts splashed down to the undersea Aquarius Reef Base, located 62 feet below the surface of the Atlantic Ocean in the Florida Keys National Marine Sanctuary. The NEEMO 21 crew will perform research both inside and outside the habitat during a 16-day simulated space mission. During simulated spacewalks carried out underwater, they will evaluate tools and mission operation techniques that could be used in future space missions, including journeys to Mars. (Photo by Karl Shreeves/NASA)

Pedestrians look at the wreckage of a vehicle lodged in a storm drain on a street in Abidjan on June 19, 2018, in which a man was reportedly found dead after floodwaters receded following an overnight downpour in the city. Fifteen people have died in Abidjan, Ivory Coast' s economic capital, during flooding caused by torrential rain overnight, Interior Minister Sidiki Diakite said. Rain poured down overnight on June 19, causing flash floods up to 2.5 metres (more than eight feet) deep, he said. (Photo by Sia Kambou/AFP Photo)

Jaison Vargas, crocodile tour guide, takes a picture of an American crocodile (Crocodylus acutus) during a tour at the Tarcoles river, in Tarcoles, Garabito municipality, Costa Rica, on March 31, 2022. Crocodile tours in the estuary of the Tarcoles River are a popular attraction for visitors to Costa Rica's Pacific coast, as the area gets back on its feet after being shaken by the pandemic. The river is home to nearly 500 species of birds and some 2,000 American crocodiles, many of which have been named after famous people. (Photo by Luis Acosta/AFP Photo)

Two young women embrace in bed together, both wearing white lace underwear. (Photo by Popperfoto/Getty Images)

Two cocks are trained for a fight in a village in Nakhon Sawan province, Thailand January 10, 2017. (Photo by Chaiwat Subprasom/Reuters)

Two friends take a quick selfie during the Grand National Festival at Aintree Racecourse on April 6, 2017 in Liverpool, England. (Photo by WENN)

The lead singer of one band talks to two bemused kids at a gig at the “Warzone Centre” in Belfast, Northern Ireland, 1980s. (Photo by Ricky Adam/Mediadrumworld)

Two sheep fight in a competition in Zhangjiakou, Hebei province, China on August 1, 2017. (Photo by Reuters/China Stringer Network)