“The Skeleton Krewe was founded in 1999 by Christopher Kirsch. Inspired by the early days of Carnival before tractors and floats replaced walking processions, the Krewe has become one of New Orleans' premier marching clubs. The Krewe began actively marching as a small group of friends, but has grown to 40 active members”. – The Skeleton Krewe. Photo: “The Skeleton Krewe 2013 – Manning”. (Photo by Kevin O'Mara)

A woman wearing a scarf to cover her face looks on as she waits for a passenger bus on a smoggy morning in New Delhi, India, November 8, 2017. The Great Smog of Delhi is an ongoing severe air-pollution event in New Delhi and adjoining areas in the National Capital Territory of India, in November 2017. Air pollution at this time peaked on both PM 2.5 and PM 10 levels. It has been reported as one of the worst levels of air quality in Delhi since 1999. (Photo by Saumya Khandelwal/Reuters)

A woman takes part in a global March for marijuana in Medellin, Colombia, May 7, 2016. The Global Marijuana March (GMM) is an annual rally held at different locations across the planet. It refers to cannabis-related events that occur on the first Saturday in May, or thereabouts, and may include marches, meetings, rallies, raves, concerts, festivals and information tables. (Photo by Fredy Builes/Reuters)

Music student Daniele Gonzalez, (centre row, L), and Australian musician Susie Park from the Minnesota Orchestra (centre row, 2nd L), react during a rehearsal in Havana, May 15, 2015. The Minnesota Orchestra will offer two concerts in Havana and is the first major U.S. orchestra to play in Cuba since 1999. The trip cost nearly $1 million. It was underwritten by Marilyn Carlson Nelson, an heir to the Carlson hotel company fortune, and her husband Glen. The U.S. government gave special permission for a direct charter flight from Minneapolis to Havana for the event, putting 4 tons of equipment and 160 people on an Airbus 330. (Photo by Alexandre Meneghini/Reuters)

Kazakh girls watch as the Russian Soyuz TMA-15 rocket carrying Canadian astronaut Robert Thirsk, European Space Agency (ESA) astronaut Frank De Winne of Belgium and Russian cosmonaut Roman Romanenko readies for take-off from the Baikonur cosmodrome, in Kazakhstan on May 27, 2009. Three astronauts, from Canada, Belgium and Russia, blasted off for the International Space Station in a landmark mission that will double its crew to six for the first time. (Photo by Dmitry Kostyukov/AFP Photo)

Firefighters watch as an air tanker drops retardant while battling the Ferguson fire in the Stanislaus National Forest, near Yosemite National Park, California on July 21, 2018. A fire that claimed the life of one firefighter and injured two others near California's Yosemite national park has almost doubled in size in three days, authorities said Friday. (Photo by Noah Berger/AFP Photo)

People leave a giant air purifier, which its inventor calls a “super tree”, in Lima's district of Jesus Maria November 24, 2014. In Peru's notoriously polluted capital Lima, local inventor Jorge Gutierrez, a retired naval engineer, is deploying the giant air purifiers that double as billboards to suck up carbon dioxide and dangerous levels of smog. (Photo by Mariana Bazo/Reuters)

A group of young men use a selfie stick to take a picture of themselves in shallow waters known as the first cataract of the River Nile outside Khartoum, Sudan, May 22, 2015. In Sudan, which faces insurgences in the western region of Darfur and along its border with breakaway South Sudan, as well as double-digit inflation and high unemployment, life goes on for young people in the capital Khartoum. (Photo by Mohamed Nureldin Abdallah/Reuters)