A roadside currency exchange vendor sorts Indian currency notes at his stall in Agartala, India, December 6, 2016. (Photo by Jayanta Dey/Reuters)

ESA astronaut Tim Peake posted this stunning image on his social media channels, commenting: “Station passed through magnificent aurora Australis last night”. Tim is set to return to Earth on 18 June 2016, bringing his six-month Principia mission to the ISS to an end. During his stay he performed more than 30 scientific experiments for ESA and taking part in numerous others from ESA's international partners. ESA and the UK Space Agency have partnered to develop many exciting educational activities around the Principia mission, aimed at sparking the interest of young children in science and space. (Photo by Tim Peake/ESA/NASA)

A dead whale is seen on the shore of the Ipanema beach in Rio de Janeiro, Brazil November 15, 2017. A biologist, Rafael Carvalho, said on Wednesday the whale appeared to have been dead for a few days. Authorities were urging beachgoers who had flocked to Ipanema on a national holiday to stay away from the animal. However, many were spotted near the carcass with some people playing in the water nearby. The whale is approximately 39 feet (12 metres) long and weighs about 25 tonnes. (Photo by Pilar Olivares/Reuters)

A policeman stands next to supporters of Kenyan President Uhuru Kenyatta lying unconscious after being beaten by police when they tried to storm through gates to get in during Kenyatta's inauguration ceremony at Kasarani stadium in Nairobi, Kenya Tuesday, November 28, 2017. Kenyatta is being sworn in on Tuesday, ending a months-long election drama that saw the first vote nullified by the country's top court and the second boycotted by the opposition. (Photo by Ben Curtis/AP Photo)

A woman dressed in traditional costume smiles at the Royal Plaza, as interest for historical clothing rises within the country, in Bangkok, Thailand April 6, 2018. (Photo by Soe Zeya Tun/Reuters)

Jean-Pierre Giagnoli walks through a crowded area of vendors hawking cat related goods at CatCon LA in Los Angeles, on Sunday, June 26, 2016. (Photo by Richard Vogel/AP Photo)

A man strikes a pose in front of a giant torta, or sandwich, during a press conference to promote the 13th annual Torta Festival, in Mexico City, Wednesday, July 20, 2016. The five day festival presents a variety of the Mexican street food made from the most exotic ingredients that include ostrich or stingray, to the classic ham, grilled steak or slow cooked pork. The festival's purpose is to maintain the tradition of eating tortas, and promote the vendors of the Mexican sandwich. (Photo by Marco Ugarte/AP Photo)

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)