A pilot inflates a hot air balloon while taking part in the 38th International Balloon Festival of Chateau-d'oex, Switzerland, 23 January 2016. The festival takes place from 23 to 31 January. (Photo by Vincent Vannay/EPA)

Radio City Music Hall Rockettes perform after days of rehearsal and routine polished to perfection at the Radio City Music Hall in New York City on July 26, 1949. (Photo by Ivan Dmitri/Getty Images)

Gisele Marie, a Muslim woman and professional heavy metal musician, plays her Gibson Flying V electric guitar during a concert in Sao Paulo December 16, 2014. Based in Sao Paulo, Marie, 42, is the granddaughter of German Catholics, and converted to Islam several months after her father passed away in 2009. Marie, who wears the Burka, has been fronting her brothers' heavy metal band “Spectrus” since 2012. (Photo by Nacho Doce/Reuters)

Small transportation boats, known as bumboats, leave trails of light as they travel across Marina Bay past the skyline of Singapore in this photo taken in 2004. Singapore holds a Jubilee weekend from 7 to 10 August to celebrate the 50th anniversary of its independence. Fifty years ago, hundreds of small boats lined the Singapore river in the city centre. Today, most small boats are gone, except a handful of neon-lit tourist ferries. Maritime trade is still the backbone of the city-state but after decades of rapid growth Singapore, which at less than half the size of London is among the world’s most densely populated nations, is also a popular tourist destination and a thriving global financial hub. (Photo by Edgar Su/Reuters)

Expedition 44 flight engineer and NASA astronaut Scott Kelly seen inside the Cupola, a special module which provides a 360-degree viewing of the Earth and the International Space Station. Kelly is one of two crew members spending an entire year in space. (Photo by Scott Kelly/NASA)

In Mumbai, the windows of new high-rise apartment blocks, old low-rise residential buildings and shantytown shacks portray the disparity in living conditions and incomes in the Indian city. Rents for a place to live range from more than $2,000 to less than $5 a month. Here: Windows and doors of an old residential building are pictured in central Mumbai October 10, 2014. The cost for buying a residential apartment in Mumbai close to the city centre ranges from 12,000 Indian rupees ($ 200) per square feet to 112,552 Indian rupees ($ 1800) per square feet. (Photo by Danish Siddiqui/Reuters)

A displaced Pakistani girl collects recyclable goods from a garbage to earn living for her family in Islamabad, Pakistan, Tuesday, January 19, 2016. (Photo by B.K. Bangash/AP Photo)

A videographer uses a drone as he takes a video of a model presenting a lingerie creation at the rehearsal for Eve's Temptation collection during China Fashion Week in Beijing, October 26, 2014. (Photo by Kim Kyung-Hoon/Reuters)