“A small British company with a dream of building a re-usable space plane has won an important endorsement from the European Space Agency (ESA) after completing key tests on its novel engine technology. Reaction Engines Ltd believes its Sabre engine, which would operate like a jet engine in the atmosphere and a rocket in space, could displace rockets for space access and transform air travel by bringing any destination on Earth to no more than four hours away”. – Chris Wickham via Reuters. Photo: Artist's impression of Skylon. (Photo by Reaction Engines Ltd)

Dajana Djuric, 25, who has worked as a chimney sweep since the age of six, cleans a chimney in Brcko, Bosnia and Herzegovina. Dajana Djuric, believed to be the only female chimney sweep in Bosnia and Herzegovina, has to contend with perilous roofs in the depth of winter. (Photo by Dado Ruvic/Reuters)

The 3D street painting “Crevasse” by artist Edgar Mueller is seen in this undated picture during the “Festival of culture”, 2008 in Dun Laoghaire, Irland. Edgar Mueller put a part of the eastern Pier into the ice age. This project has been supported by the Goethe Institution Germany. (Photo by Edgar Mueller/Getty Images)

“El rio mas bonito del Mundo”, the most beautiful river of the world, the “River of five colors”, the “Rainbow River”, or even the “Escaped from Paradise”, are the shimmering appellations that Colombians give to Cano Cristales, a small stream located in the heart of the Macarena National Park, 150 km (93 miles) south of Bogota. Photo: A waterfall is seen at the end of the rainy season, in August, when the water level finally decreases, in the Cano Cristales RIver in the Sierra de la Macarena in Colombia. It has become covered with a bright pink endemic aquatic plant, Macarenia Clavigera. (Photo by Olivier Grunewald)

Three very colouful alpacas enjoy the hot weather at Toft Farm, Rugby, on July 19, 2013. (Photo by Caters News)

Mount Sinabung continues to spew thick smoke into the air in Karo, North Sumatra on October 30, 2020. (Photo by Albert Ivan Damanik/Anadolu Agency via Getty Images)

Models sit backstage during an outdoor show at Dakar Fashion week on December 12, 2020 just outside Dakar, Senegal. With Senegal's low incidence of Covid-19, Dakar's marquee fashion event looked markedly more normal than its counterparts in other global capitals, whose fashion weeks were heavily curtailed or canceled. (Photo by Finbarr O'Reilly/Getty Images)

A group of girls hit the town in York, United Kingdom on December 30, 2020. Revellers hit the streets for a final drink before being plunged into Tier 4 lockdown. (Photo by Nb press ltd)