Kha Tu Ngoc rests in her two- square- meter house in Ho Chi Minh City on May 2, 2018. The “micro- house” dwellings are dotted throughout Vietnam' s bustling southern hub, occupied by families clinging to postage stamp- sized plots a city developing at breakneck pace. Tucked away in winding alleys, nestled under new condo developments or sandwiched between street food stalls and shops, the tiny houses are easily missed by the unattentive passerby. (Photo by Thanh Nguyen/AFP Photo)

A prototype of the Space Exploration Technologies Corp. (SpaceX) Starship launch vehicle stands during an event at the SpaceX launch facility in Cameron County, Texas, U.S., on Saturday, September 28, 2019. Elon Musk gave space fans an update Saturday evening on the status of “Starship”, the next-generation vehicle his SpaceX plans to use to eventually take humans to Mars. (Photo by Callaghan O'Hare/Reuters)

Protestors from the Extinction Rebellion march on day six of protests stopping traffic in the city district of Melbourne, Australia on October 12, 2019. (Photo by ydney Low/ZUMA Wire/Rex Features/Shutterstock)

A police officer reacts to flames during a protest against Chile's government in Santiago, Chile on November 4, 2019. Unrest began in Chile last October 18 with protests against a rise in transport tickets and other austerity measures and descended into vandalism, looting, and clashes between demonstrators and police. Protesters are angry about low salaries and pensions, poor public healthcare and education, and a yawning gap between rich and poor. (Photo by Henry Romero/Reuters)

General view of a herbal store in Cairo, Egypt January 10, 2017. In an economic crisis that has led to a shortage of medicines, Egyptians are skipping trips to drug stores and instead turning to herbal remedies to treat every-day illnesses. (Photo by Mohamed Abd El Ghany/Reuters)

A participant wrestles with a pig in the “greased pig contest” at the Festival du Cochon (Pig Festival) in Sainte-Perpetue, Quebec August 8, 2015. (Photo by Christinne Muschi/Reuters)

A man rides a horse through flames during the annual “Luminarias” celebration on the eve of Saint Anthony's day, Spain's patron saint of animals, in the village of San Bartolome de Pinares, northwest of Madrid, Spain, January 16, 2017. (Photo by Paul Hanna/Reuters)

British sailors taking shore leave on the British dependency of Gibraltar visit the Suiza Bar to watch a Spanish dancer perform on August 05, 1954. These Spanish entertainers are under contract and must return over the border by 11 o'clock. (Photo by Bert Hardy/Getty Images)